Science.gov

Sample records for digital image processing

  1. Digital image processing.

    PubMed

    Seeram, Euclid

    2004-01-01

    Digital image processing is now commonplace in radiology, nuclear medicine and sonography. This article outlines underlying principles and concepts of digital image processing. After completing this article, readers should be able to: List the limitations of film-based imaging. Identify major components of a digital imaging system. Describe the history and application areas of digital image processing. Discuss image representation and the fundamentals of digital image processing. Outline digital image processing techniques and processing operations used in selected imaging modalities. Explain the basic concepts and visualization tools used in 3-D and virtual reality imaging. Recognize medical imaging informatics as a new area of specialization for radiologic technologists.

  2. Digital image processing

    NASA Technical Reports Server (NTRS)

    Bernstein, R.; Ferneyhough, D. G., Jr.

    1975-01-01

    The Federal Systems Division of IBM has developed an image processing facility to experimentally process, view, and record digital image data. This facility has been used to support LANDSAT digital image processing investigations and advanced image processing research and development. A brief description of the facility is presented, some techniques that have been developed to correct the image data are discussed, and some results obtained by users of the facility are described.

  3. Metric Aspects of Digital Images and Digital Image Processing.

    DTIC Science & Technology

    1984-09-01

    image files were synthesized aerial images, produced using the program SIM. This program makes use of a digital terrain model containing gray shade...the Arizona test data. This test data was derived from a digitized stereo model formed by two nearly vertical images taken in October 1066 near... digital image processing operations will be investigated in a manner similar to compression. 7) It is hoped that the ability to quantitatively assess

  4. Digital image processing in cephalometric analysis.

    PubMed

    Jäger, A; Döler, W; Schormann, T

    1989-01-01

    Digital image processing methods were applied to improve the practicability of cephalometric analysis. The individual X-ray film was digitized by the aid of a high resolution microscope-photometer. Digital processing was done using a VAX 8600 computer system. An improvement of the image quality was achieved by means of various digital enhancement and filtering techniques.

  5. Digital processing of radiographic images

    NASA Technical Reports Server (NTRS)

    Bond, A. D.; Ramapriyan, H. K.

    1973-01-01

    Some techniques are presented and the software documentation for the digital enhancement of radiographs. Both image handling and image processing operations are considered. The image handling operations dealt with are: (1) conversion of format of data from packed to unpacked and vice versa; (2) automatic extraction of image data arrays; (3) transposition and 90 deg rotations of large data arrays; (4) translation of data arrays for registration; and (5) reduction of the dimensions of data arrays by integral factors. Both the frequency and the spatial domain approaches are presented for the design and implementation of the image processing operation. It is shown that spatial domain recursive implementation of filters is much faster than nonrecursive implementations using fast fourier transforms (FFT) for the cases of interest in this work. The recursive implementation of a class of matched filters for enhancing image signal to noise ratio is described. Test patterns are used to illustrate the filtering operations. The application of the techniques to radiographic images of metallic structures is demonstrated through several examples.

  6. How Digital Image Processing Became Really Easy

    NASA Astrophysics Data System (ADS)

    Cannon, Michael

    1988-02-01

    In the early and mid-1970s, digital image processing was the subject of intense university and corporate research. The research lay along two lines: (1) developing mathematical techniques for improving the appearance of or analyzing the contents of images represented in digital form, and (2) creating cost-effective hardware to carry out these techniques. The research has been very effective, as evidenced by the continued decline of image processing as a research topic, and the rapid increase of commercial companies to market digital image processing software and hardware.

  7. Eliminating "Hotspots" in Digital Image Processing

    NASA Technical Reports Server (NTRS)

    Salomon, P. M.

    1984-01-01

    Signals from defective picture elements rejected. Image processing program for use with charge-coupled device (CCD) or other mosaic imager augmented with algorithm that compensates for common type of electronic defect. Algorithm prevents false interpretation of "hotspots". Used for robotics, image enhancement, image analysis and digital television.

  8. Eliminating "Hotspots" in Digital Image Processing

    NASA Technical Reports Server (NTRS)

    Salomon, P. M.

    1984-01-01

    Signals from defective picture elements rejected. Image processing program for use with charge-coupled device (CCD) or other mosaic imager augmented with algorithm that compensates for common type of electronic defect. Algorithm prevents false interpretation of "hotspots". Used for robotics, image enhancement, image analysis and digital television.

  9. Checking Fits With Digital Image Processing

    NASA Technical Reports Server (NTRS)

    Davis, R. M.; Geaslen, W. D.

    1988-01-01

    Computer-aided video inspection of mechanical and electrical connectors feasible. Report discusses work done on digital image processing for computer-aided interface verification (CAIV). Two kinds of components examined: mechanical mating flange and electrical plug.

  10. CT Image Processing Using Public Digital Networks

    PubMed Central

    Rhodes, Michael L.; Azzawi, Yu-Ming; Quinn, John F.; Glenn, William V.; Rothman, Stephen L.G.

    1984-01-01

    Nationwide commercial computer communication is now commonplace for those applications where digital dialogues are generally short and widely distributed, and where bandwidth does not exceed that of dial-up telephone lines. Image processing using such networks is prohibitive because of the large volume of data inherent to digital pictures. With a blend of increasing bandwidth and distributed processing, network image processing becomes possible. This paper examines characteristics of a digital image processing service for a nationwide network of CT scanner installations. Issues of image transmission, data compression, distributed processing, software maintenance, and interfacility communication are also discussed. Included are results that show the volume and type of processing experienced by a network of over 50 CT scanners for the last 32 months.

  11. Digital Image Processing in Private Industry.

    ERIC Educational Resources Information Center

    Moore, Connie

    1986-01-01

    Examines various types of private industry optical disk installations in terms of business requirements for digital image systems in five areas: records management; transaction processing; engineering/manufacturing; information distribution; and office automation. Approaches for implementing image systems are addressed as well as key success…

  12. Digital Image Processing in Private Industry.

    ERIC Educational Resources Information Center

    Moore, Connie

    1986-01-01

    Examines various types of private industry optical disk installations in terms of business requirements for digital image systems in five areas: records management; transaction processing; engineering/manufacturing; information distribution; and office automation. Approaches for implementing image systems are addressed as well as key success…

  13. Applications of Digital Image Processing 11

    NASA Technical Reports Server (NTRS)

    Cho, Y. -C.

    1988-01-01

    A new technique, digital image velocimetry, is proposed for the measurement of instantaneous velocity fields of time dependent flows. A time sequence of single-exposure images of seed particles are captured with a high-speed camera, and a finite number of the single-exposure images are sampled within a prescribed period in time. The sampled images are then digitized on an image processor, enhanced, and superimposed to construct an image which is equivalent to a multiple exposure image used in both laser speckle velocimetry and particle image velocimetry. The superimposed image and a single-exposure Image are digitally Fourier transformed for extraction of information on the velocity field. A great enhancement of the dynamic range of the velocity measurement is accomplished through the new technique by manipulating the Fourier transform of both the single-exposure image and the superimposed image. Also the direction of the velocity vector is unequivocally determined. With the use of a high-speed video camera, the whole process from image acquisition to velocity determination can be carried out electronically; thus this technique can be developed into a real-time capability.

  14. Digital radiography image quality: image processing and display.

    PubMed

    Krupinski, Elizabeth A; Williams, Mark B; Andriole, Katherine; Strauss, Keith J; Applegate, Kimberly; Wyatt, Margaret; Bjork, Sandra; Seibert, J Anthony

    2007-06-01

    This article on digital radiography image processing and display is the second of two articles written as part of an intersociety effort to establish image quality standards for digital and computed radiography. The topic of the other paper is digital radiography image acquisition. The articles were developed collaboratively by the ACR, the American Association of Physicists in Medicine, and the Society for Imaging Informatics in Medicine. Increasingly, medical imaging and patient information are being managed using digital data during acquisition, transmission, storage, display, interpretation, and consultation. The management of data during each of these operations may have an impact on the quality of patient care. These articles describe what is known to improve image quality for digital and computed radiography and to make recommendations on optimal acquisition, processing, and display. The practice of digital radiography is a rapidly evolving technology that will require timely revision of any guidelines and standards.

  15. Digital image processing of vascular angiograms

    NASA Technical Reports Server (NTRS)

    Selzer, R. H.; Beckenbach, E. S.; Blankenhorn, D. H.; Crawford, D. W.; Brooks, S. H.

    1975-01-01

    The paper discusses the estimation of the degree of atherosclerosis in the human femoral artery through the use of a digital image processing system for vascular angiograms. The film digitizer uses an electronic image dissector camera to scan the angiogram and convert the recorded optical density information into a numerical format. Another processing step involves locating the vessel edges from the digital image. The computer has been programmed to estimate vessel abnormality through a series of measurements, some derived primarily from the vessel edge information and others from optical density variations within the lumen shadow. These measurements are combined into an atherosclerosis index, which is found in a post-mortem study to correlate well with both visual and chemical estimates of atherosclerotic disease.

  16. Image processing of digital chest ionograms.

    PubMed

    Yarwood, J R; Moores, B M

    1988-10-01

    A number of image-processing techniques have been applied to a digital ionographic chest image in order to evaluate their possible effects on this type of image. In order to quantify any effect, a simulated lesion was superimposed on the image at a variety of locations representing different types of structural detail. Visualization of these lesions was evaluated by a number of observers both pre- and post-processing operations. The operations employed included grey-scale transformations, histogram operations, edge-enhancement and smoothing functions. The resulting effects of these operations on the visualization of the simulated lesions are discussed.

  17. Fundamental Concepts of Digital Image Processing

    DOE R&D Accomplishments Database

    Twogood, R. E.

    1983-03-01

    The field of a digital-image processing has experienced dramatic growth and increasingly widespread applicability in recent years. Fortunately, advances in computer technology have kept pace with the rapid growth in volume of image data in these and other applications. Digital image processing has become economical in many fields of research and in industrial and military applications. While each application has requirements unique from the others, all are concerned with faster, cheaper, more accurate, and more extensive computation. The trend is toward real-time and interactive operations, where the user of the system obtains preliminary results within a short enough time that the next decision can be made by the human processor without loss of concentration on the task at hand. An example of this is the obtaining of two-dimensional (2-D) computer-aided tomography (CAT) images. A medical decision might be made while the patient is still under observation rather than days later.

  18. Image processing techniques for digital orthophotoquad production

    USGS Publications Warehouse

    Hood, Joy J.; Ladner, L. J.; Champion, Richard A.

    1989-01-01

    Orthophotographs have long been recognized for their value as supplements or alternatives to standard maps. Recent trends towards digital cartography have resulted in efforts by the US Geological Survey to develop a digital orthophotoquad production system. Digital image files were created by scanning color infrared photographs on a microdensitometer. Rectification techniques were applied to remove tile and relief displacement, thereby creating digital orthophotos. Image mosaicking software was then used to join the rectified images, producing digital orthophotos in quadrangle format.

  19. A brief review of digital image processing

    NASA Technical Reports Server (NTRS)

    Billingsley, F. C.

    1975-01-01

    The review is presented with particular reference to Skylab S-192 and Landsat MSS imagery. Attention is given to rectification (calibration) processing with emphasis on geometric correction of image distortions. Image enhancement techniques (e.g., the use of high pass digital filters to eliminate gross shading to allow emphasis of the fine detail) are described along with data analysis and system considerations (software philosophy).

  20. [Digital thoracic radiology: devices, image processing, limits].

    PubMed

    Frija, J; de Géry, S; Lallouet, F; Guermazi, A; Zagdanski, A M; De Kerviler, E

    2001-09-01

    In a first part, the different techniques of digital thoracic radiography are described. Since computed radiography with phosphore plates are the most commercialized it is more emphasized. But the other detectors are also described, as the drum coated with selenium and the direct digital radiography with selenium detectors. The other detectors are also studied in particular indirect flat panels detectors and the system with four high resolution CCD cameras. In a second step the most important image processing are discussed: the gradation curves, the unsharp mask processing, the system MUSICA, the dynamic range compression or reduction, the soustraction with dual energy. In the last part the advantages and the drawbacks of computed thoracic radiography are emphasized. The most important are the almost constant good quality of the pictures and the possibilities of image processing.

  1. Digital image processing of cephalometric radiographs: a preliminary report.

    PubMed

    Jackson, P H; Dickson, G C; Birnie, D J

    1985-07-01

    The principles of image capture, image storage and image processing in digital radiology are described. The enhancement of radiographic images using digital image processing techniques and its application to cephalometry is discussed. The results of a pilot study which compared some common cephalometric measurements made from manual point identification with those made by direct digitization of digital radiographic images from video monitors are presented. Although in an early stage of development, the results from the image processing system were comparable with those obtained by traditional methods.

  2. On digital image processing technology and application in geometric measure

    NASA Astrophysics Data System (ADS)

    Yuan, Jiugen; Xing, Ruonan; Liao, Na

    2014-04-01

    Digital image processing technique is an emerging science that emerging with the development of semiconductor integrated circuit technology and computer science technology since the 1960s.The article introduces the digital image processing technique and principle during measuring compared with the traditional optical measurement method. It takes geometric measure as an example and introduced the development tendency of digital image processing technology from the perspective of technology application.

  3. Multiscale image processing and antiscatter grids in digital radiography.

    PubMed

    Lo, Winnie Y; Hornof, William J; Zwingenberger, Allison L; Robertson, Ian D

    2009-01-01

    Scatter radiation is a source of noise and results in decreased signal-to-noise ratio and thus decreased image quality in digital radiography. We determined subjectively whether a digitally processed image made without a grid would be of similar quality to an image made with a grid but without image processing. Additionally the effects of exposure dose and of a using a grid with digital radiography on overall image quality were studied. Thoracic and abdominal radiographs of five dogs of various sizes were made. Four acquisition techniques were included (1) with a grid, standard exposure dose, digital image processing; (2) without a grid, standard exposure dose, digital image processing; (3) without a grid, half the exposure dose, digital image processing; and (4) with a grid, standard exposure dose, no digital image processing (to mimic a film-screen radiograph). Full-size radiographs as well as magnified images of specific anatomic regions were generated. Nine reviewers rated the overall image quality subjectively using a five-point scale. All digitally processed radiographs had higher overall scores than nondigitally processed radiographs regardless of patient size, exposure dose, or use of a grid. The images made at half the exposure dose had a slightly lower quality than those made at full dose, but this was only statistically significant in magnified images. Using a grid with digital image processing led to a slight but statistically significant increase in overall quality when compared with digitally processed images made without a grid but whether this increase in quality is clinically significant is unknown.

  4. Digital Imaging

    NASA Technical Reports Server (NTRS)

    1986-01-01

    Digital Imaging is the computer processed numerical representation of physical images. Enhancement of images results in easier interpretation. Quantitative digital image analysis by Perceptive Scientific Instruments, locates objects within an image and measures them to extract quantitative information. Applications are CAT scanners, radiography, microscopy in medicine as well as various industrial and manufacturing uses. The PSICOM 327 performs all digital image analysis functions. It is based on Jet Propulsion Laboratory technology, is accurate and cost efficient.

  5. Applications of digital image processing IX

    SciTech Connect

    Tescher, A.G.

    1986-01-01

    This book contains the proceedings of SPIE - The International Society for Optical Engineering. The first session covers image compression and includes papers such as ''Knowledge-based image bandwidth compression.'' Session two is about instrumentation such as ''Real-time inspection of currency'' and ''Experimental digital image processor.'' Session three discusses theoretical concepts such as ''Study of texture segmentation.'' Session four is about algorithms. One such topic is ''Dynamic ordered dither algorithm.'' Session five covers registration and modeling. For example, one paper is ''3D-motion estimation from projections.'' Session six is about restoration and enhancement. Papers include ''Wobble error correction for laser scanners'' and ''Robotics with computer Vision.''

  6. Digital processing of radiographic images from PACS to publishing.

    PubMed

    Christian, M E; Davidson, H C; Wiggins, R H; Berges, G; Cannon, G; Jackson, G; Chapman, B; Harnsberger, H R

    2001-03-01

    Several studies have addressed the implications of filmless radiologic imaging on telemedicine, diagnostic ability, and electronic teaching files. However, many publishers still require authors to submit hard-copy images for publication of articles and textbooks. This study compares the quality digital images directly exported from picture archive and communications systems (PACS) to images digitized from radiographic film. The authors evaluated the quality of publication-grade glossy photographs produced from digital radiographic images using 3 different methods: (1) film images digitized using a desktop scanner and then printed, (2) digital images obtained directly from PACS then printed, and (3) digital images obtained from PACS and processed to improve sharpness prior to printing. Twenty images were printed using each of the 3 different methods and rated for quality by 7 radiologists. The results were analyzed for statistically significant differences among the image sets. Subjective evaluations of the filmless images found them to be of equal or better quality than the digitized images. Direct electronic transfer of PACS images reduces the number of steps involved in creating publication-quality images as well as providing the means to produce high-quality radiographic images in a digital environment.

  7. A color image processing pipeline for digital microscope

    NASA Astrophysics Data System (ADS)

    Liu, Yan; Liu, Peng; Zhuang, Zhefeng; Chen, Enguo; Yu, Feihong

    2012-10-01

    Digital microscope has found wide application in the field of biology, medicine et al. A digital microscope differs from traditional optical microscope in that there is no need to observe the sample through an eyepiece directly, because the optical image is projected directly on the CCD/CMOS camera. However, because of the imaging difference between human eye and sensor, color image processing pipeline is needed for the digital microscope electronic eyepiece to get obtain fine image. The color image pipeline for digital microscope, including the procedures that convert the RAW image data captured by sensor into real color image, is of great concern to the quality of microscopic image. The color pipeline for digital microscope is different from digital still cameras and video cameras because of the specific requirements of microscopic image, which should have the characters of high dynamic range, keeping the same color with the objects observed and a variety of image post-processing. In this paper, a new color image processing pipeline is proposed to satisfy the requirements of digital microscope image. The algorithm of each step in the color image processing pipeline is designed and optimized with the purpose of getting high quality image and accommodating diverse user preferences. With the proposed pipeline implemented on the digital microscope platform, the output color images meet the various analysis requirements of images in the medicine and biology fields very well. The major steps of color imaging pipeline proposed include: black level adjustment, defect pixels removing, noise reduction, linearization, white balance, RGB color correction, tone scale correction and gamma correction.

  8. Detecting jaundice by using digital image processing

    NASA Astrophysics Data System (ADS)

    Castro-Ramos, J.; Toxqui-Quitl, C.; Villa Manriquez, F.; Orozco-Guillen, E.; Padilla-Vivanco, A.; Sánchez-Escobar, JJ.

    2014-03-01

    When strong Jaundice is presented, babies or adults should be subject to clinical exam like "serum bilirubin" which can cause traumas in patients. Often jaundice is presented in liver disease such as hepatitis or liver cancer. In order to avoid additional traumas we propose to detect jaundice (icterus) in newborns or adults by using a not pain method. By acquiring digital images in color, in palm, soles and forehead, we analyze RGB attributes and diffuse reflectance spectra as the parameter to characterize patients with either jaundice or not, and we correlate that parameters with the level of bilirubin. By applying support vector machine we distinguish between healthy and sick patients.

  9. Digital image processing for photo-reconnaissance applications

    NASA Technical Reports Server (NTRS)

    Billingsley, F. C.

    1972-01-01

    Digital image-processing techniques developed for processing pictures from NASA space vehicles are analyzed in terms of enhancement, quantitative restoration, and information extraction. Digital filtering, and the action of a high frequency filter in the real and Fourier domain are discussed along with color and brightness.

  10. A review of some digital image processing in cometary research

    NASA Astrophysics Data System (ADS)

    Larson, S. M.

    The development of electronic digitizers, digital detector arrays and modern high speed computer processing has led to more efficient, quantitative methods of studying the spatial, temporal and photometric properties of cometary phenomena. Digital image processing techniques are being used and further developed to reduce two dimensional data, to enhance the visibility of cometary features, and to quantify spatial and temporal changes. Some of these methods are reviewed, and their merits and limitations are discussed.

  11. Results of precision processing (scene correction) of ERTS-1 images using digital image processing techniques

    NASA Technical Reports Server (NTRS)

    Bernstein, R.

    1973-01-01

    ERTS-1 MSS and RBV data recorded on computer compatible tapes have been analyzed and processed, and preliminary results have been obtained. No degradation of intensity (radiance) information occurred in implementing the geometric correction. The quality and resolution of the digitally processed images are very good, due primarily to the fact that the number of film generations and conversions is reduced to a minimum. Processing times of digitally processed images are about equivalent to the NDPF electro-optical processor.

  12. Application of digital image processing techniques to astronomical imagery 1977

    NASA Technical Reports Server (NTRS)

    Lorre, J. J.; Lynn, D. J.

    1978-01-01

    Nine specific techniques of combination of techniques developed for applying digital image processing technology to existing astronomical imagery are described. Photoproducts are included to illustrate the results of each of these investigations.

  13. Low cost 3D scanning process using digital image processing

    NASA Astrophysics Data System (ADS)

    Aguilar, David; Romero, Carlos; Martínez, Fernando

    2017-02-01

    This paper shows the design and building of a low cost 3D scanner, able to digitize solid objects through contactless data acquisition, using active object reflection. 3D scanners are used in different applications such as: science, engineering, entertainment, etc; these are classified in: contact scanners and contactless ones, where the last ones are often the most used but they are expensive. This low-cost prototype is done through a vertical scanning of the object using a fixed camera and a mobile horizontal laser light, which is deformed depending on the 3-dimensional surface of the solid. Using digital image processing an analysis of the deformation detected by the camera was done; it allows determining the 3D coordinates using triangulation. The obtained information is processed by a Matlab script, which gives to the user a point cloud corresponding to each horizontal scanning done. The obtained results show an acceptable quality and significant details of digitalized objects, making this prototype (built on LEGO Mindstorms NXT kit) a versatile and cheap tool, which can be used for many applications, mainly by engineering students.

  14. Digital interactive image analysis by array processing

    NASA Technical Reports Server (NTRS)

    Sabels, B. E.; Jennings, J. D.

    1973-01-01

    An attempt is made to draw a parallel between the existing geophysical data processing service industries and the emerging earth resources data support requirements. The relationship of seismic data analysis to ERTS data analysis is natural because in either case data is digitally recorded in the same format, resulting from remotely sensed energy which has been reflected, attenuated, shifted and degraded on its path from the source to the receiver. In the seismic case the energy is acoustic, ranging in frequencies from 10 to 75 cps, for which the lithosphere appears semi-transparent. In earth survey remote sensing through the atmosphere, visible and infrared frequency bands are being used. Yet the hardware and software required to process the magnetically recorded data from the two realms of inquiry are identical and similar, respectively. The resulting data products are similar.

  15. [Generation and processing of digital images in radiodiagnosis].

    PubMed

    Bajla, I; Belan, V

    1993-05-01

    The paper describes universal principles of diagnostic imaging. The attention is focused particularly on digital image generation in medicine. The methodology of display visualization of measured data is discussed. The problems of spatial relation representation and visual perception of image brightness are mentioned. The methodological issues of digital image processing (DIP) are discussed, particularly the relation of DIP to the other related disciplines, fundamental tasks in DIP and classification of DIP operations from the computational viewpoint. The following examples of applying DIP operations in diagnostic radiology are overviewed: local contrast enhancement in digital image, spatial filtering, quantitative texture analysis, synthesis of the 3D pseudospatial image based on the 2D tomogram set, multimodal processing of medical images. New trends of application of DIP methods in diagnostic radiology are outlined: evaluation of the diagnostic efficiency of DIP operations by means of ROC analysis, construction of knowledge-based systems of DIP in medicine. (Fig. 12, Ref. 26.)

  16. Experiences with digital processing of images at INPE

    NASA Technical Reports Server (NTRS)

    Mascarenhas, N. D. A. (Principal Investigator)

    1984-01-01

    Four different research experiments with digital image processing at INPE will be described: (1) edge detection by hypothesis testing; (2) image interpolation by finite impulse response filters; (3) spatial feature extraction methods in multispectral classification; and (4) translational image registration by sequential tests of hypotheses.

  17. Sliding mean edge estimation. [in digital image processing

    NASA Technical Reports Server (NTRS)

    Ford, G. E.

    1978-01-01

    A method for determining the locations of the major edges of objects in digital images is presented. The method is based on an algorithm utilizing maximum likelihood concepts. An image line-scan interval is processed to determine if an edge exists within the interval and its location. The proposed algorithm has demonstrated good results even in noisy images.

  18. Restoration Of Faded Color Photographs By Digital Image Processing

    NASA Astrophysics Data System (ADS)

    Gschwind, Rudolf

    1989-10-01

    Color photographs possess a poor stability towards light, chemicals heat and humidity. As a consequence, the colors of photographs deteriorate with time. Because of the complexity of processes that cause the dyes to fade, it is impossible to restore the images by chemical means. It is therefore attempted to restore faded color films by means of digital image processing.

  19. Digital image processing of vascular angiograms

    NASA Technical Reports Server (NTRS)

    Selzer, R. H.; Blankenhorn, D. H.; Beckenbach, E. S.; Crawford, D. W.; Brooks, S. H.

    1975-01-01

    A computer image processing technique was developed to estimate the degree of atherosclerosis in the human femoral artery. With an angiographic film of the vessel as input, the computer was programmed to estimate vessel abnormality through a series of measurements, some derived primarily from the vessel edge information and others from optical density variations within the lumen shadow. These measurements were combined into an atherosclerosis index, which was found to correlate well with both visual and chemical estimates of atherosclerotic disease.

  20. Digital image processing of bone - Problems and potentials

    NASA Technical Reports Server (NTRS)

    Morey, E. R.; Wronski, T. J.

    1980-01-01

    The development of a digital image processing system for bone histomorphometry and fluorescent marker monitoring is discussed. The system in question is capable of making measurements of UV or light microscope features on a video screen with either video or computer-generated images, and comprises a microscope, low-light-level video camera, video digitizer and display terminal, color monitor, and PDP 11/34 computer. Capabilities demonstrated in the analysis of an undecalcified rat tibia include the measurement of perimeter and total bone area, and the generation of microscope images, false color images, digitized images and contoured images for further analysis. Software development will be based on an existing software library, specifically the mini-VICAR system developed at JPL. It is noted that the potentials of the system in terms of speed and reliability far exceed any problems associated with hardware and software development.

  1. Digital image processing of bone - Problems and potentials

    NASA Technical Reports Server (NTRS)

    Morey, E. R.; Wronski, T. J.

    1980-01-01

    The development of a digital image processing system for bone histomorphometry and fluorescent marker monitoring is discussed. The system in question is capable of making measurements of UV or light microscope features on a video screen with either video or computer-generated images, and comprises a microscope, low-light-level video camera, video digitizer and display terminal, color monitor, and PDP 11/34 computer. Capabilities demonstrated in the analysis of an undecalcified rat tibia include the measurement of perimeter and total bone area, and the generation of microscope images, false color images, digitized images and contoured images for further analysis. Software development will be based on an existing software library, specifically the mini-VICAR system developed at JPL. It is noted that the potentials of the system in terms of speed and reliability far exceed any problems associated with hardware and software development.

  2. Digital image processing of earth observation sensor data

    NASA Technical Reports Server (NTRS)

    Bernstein, R.

    1976-01-01

    This paper describes digital image processing techniques that were developed to precisely correct Landsat multispectral earth observation data and gives illustrations of the results achieved, e.g., geometric corrections with an error of less than one picture element, a relative error of one-fourth picture element, and no radiometric error effect. Techniques for enhancing the sensor data, digitally mosaicking multiple scenes, and extracting information are also illustrated.

  3. Digital image processing for the earth resources technology satellite data.

    NASA Technical Reports Server (NTRS)

    Will, P. M.; Bakis, R.; Wesley, M. A.

    1972-01-01

    This paper discusses the problems of digital processing of the large volumes of multispectral image data that are expected to be received from the ERTS program. Correction of geometric and radiometric distortions are discussed and a byte oriented implementation is proposed. CPU timing estimates are given for a System/360 Model 67, and show that a processing throughput of 1000 image sets per week is feasible.

  4. Integrating digital topology in image-processing libraries.

    PubMed

    Lamy, Julien

    2007-01-01

    This paper describes a method to integrate digital topology informations in image-processing libraries. This additional information allows a library user to write algorithms respecting topological constraints, for example, a seed fill or a skeletonization algorithm. As digital topology is absent from most image-processing libraries, such constraints cannot be fulfilled. We describe and give code samples for all the structures necessary for this integration, and show a use case in the form of a homotopic thinning filter inside ITK. The obtained filter can be up to a hundred times as fast as ITK's thinning filter and works for any image dimension. This paper mainly deals of integration within ITK, but can be adapted with only minor modifications to other image-processing libraries.

  5. Digital imaging.

    PubMed

    Daniel, Gregory B

    2009-07-01

    Medical imaging is rapidly moving toward a digital-based image system. An understanding of the principles of digital imaging is necessary to evaluate features of imaging systems and can play an important role in purchasing decisions.

  6. Digital Image Processing application to spray and flammability studies

    NASA Technical Reports Server (NTRS)

    Hernan, M. A.; Parikh, P.; Sarohia, V.

    1985-01-01

    Digital Image Processing has been integrated into a new technique for measurements of fuel spray characteristics. The advantages of this technique are: a wide dynamic range of droplet sizes, accounting for nonspherical droplet shapes not possible with other spray assessment techniques. Finally, the technique has been applied to the study of turbojet engine fuel nozzle atomization performance with Jet A and antimisting fuel.

  7. An image processing system for digital chest X-ray images.

    PubMed

    Cocklin, M; Gourlay, A; Jackson, P; Kaye, G; Miessler, M; Kerr, I; Lams, P

    1984-01-01

    This paper investigates the requirements for image processing of digital chest X-ray images. These images are conventionally recorded on film and are characterised by large size, wide dynamic range and high resolution. X-ray detection systems are now becoming available for capturing these images directly in photoelectronic-digital form. In this report, the hardware and software facilities required for handling these images are described. These facilities include high resolution digital image displays, programmable video look up tables, image stores for image capture and processing and a full range of software tools for image manipulation. Examples are given of the application of digital image processing techniques to this class of image.

  8. Matching rendered and real world images by digital image processing

    NASA Astrophysics Data System (ADS)

    Mitjà, Carles; Bover, Toni; Bigas, Miquel; Escofet, Jaume

    2010-05-01

    Recent advances in computer-generated images (CGI) have been used in commercial and industrial photography providing a broad scope in product advertising. Mixing real world images with those rendered from virtual space software shows a more or less visible mismatching between corresponding image quality performance. Rendered images are produced by software which quality performance is only limited by the resolution output. Real world images are taken with cameras with some amount of image degradation factors as lens residual aberrations, diffraction, sensor low pass anti aliasing filters, color pattern demosaicing, etc. The effect of all those image quality degradation factors can be characterized by the system Point Spread Function (PSF). Because the image is the convolution of the object by the system PSF, its characterization shows the amount of image degradation added to any taken picture. This work explores the use of image processing to degrade the rendered images following the parameters indicated by the real system PSF, attempting to match both virtual and real world image qualities. The system MTF is determined by the slanted edge method both in laboratory conditions and in the real picture environment in order to compare the influence of the working conditions on the device performance; an approximation to the system PSF is derived from the two measurements. The rendered images are filtered through a Gaussian filter obtained from the taking system PSF. Results with and without filtering are shown and compared measuring the contrast achieved in different final image regions.

  9. Kinematic analysis of human walking gait using digital image processing.

    PubMed

    O'Malley, M; de Paor, D L

    1993-07-01

    A system using digital image processing techniques for kinematic analysis of human gait has been developed. The system is cheap, easy to use, automated and provides useful detailed quantitative information to the medical profession. Passive markers comprising black annuli on white card are placed on the anatomical landmarks of the subject. Digital images at the standard television rate of 25 per second are acquired of the subject walking past a white background. The images are obtained, stored and processed using standard commercially available hardware, i.e. video camera, video recorder, digital framestore and an IBM PC. Using a single-threshold grey level, all the images are thresholded to produce binary images. An automatic routine then uses a set of pattern recognition algorithms to locate accurately and consistently the markers in each image. The positions of the markers are analysed to determine to which anatomical landmark they correspond, and thus a stick diagram for each image is obtained. There is also a facility where the positions of the markers may be entered manually and errors corrected. The results may be presented in a variety of ways: stick diagram animation, sagittal displacement graphs, flexion diagrams and gait parameters.

  10. Evaluation of clinical image processing algorithms used in digital mammography.

    PubMed

    Zanca, Federica; Jacobs, Jurgen; Van Ongeval, Chantal; Claus, Filip; Celis, Valerie; Geniets, Catherine; Provost, Veerle; Pauwels, Herman; Marchal, Guy; Bosmans, Hilde

    2009-03-01

    Screening is the only proven approach to reduce the mortality of breast cancer, but significant numbers of breast cancers remain undetected even when all quality assurance guidelines are implemented. With the increasing adoption of digital mammography systems, image processing may be a key factor in the imaging chain. Although to our knowledge statistically significant effects of manufacturer-recommended image processings have not been previously demonstrated, the subjective experience of our radiologists, that the apparent image quality can vary considerably between different algorithms, motivated this study. This article addresses the impact of five such algorithms on the detection of clusters of microcalcifications. A database of unprocessed (raw) images of 200 normal digital mammograms, acquired with the Siemens Novation DR, was collected retrospectively. Realistic simulated microcalcification clusters were inserted in half of the unprocessed images. All unprocessed images were subsequently processed with five manufacturer-recommended image processing algorithms (Agfa Musica 1, IMS Raffaello Mammo 1.2, Sectra Mamea AB Sigmoid, Siemens OPVIEW v2, and Siemens OPVIEW v1). Four breast imaging radiologists were asked to locate and score the clusters in each image on a five point rating scale. The free-response data were analyzed by the jackknife free-response receiver operating characteristic (JAFROC) method and, for comparison, also with the receiver operating characteristic (ROC) method. JAFROC analysis revealed highly significant differences between the image processings (F = 8.51, p < 0.0001), suggesting that image processing strongly impacts the detectability of clusters. Siemens OPVIEW2 and Siemens OPVIEW1 yielded the highest and lowest performances, respectively. ROC analysis of the data also revealed significant differences between the processing but at lower significance (F = 3.47, p = 0.0305) than JAFROC. Both statistical analysis methods revealed that the

  11. Computer image processing - The Viking experience. [digital enhancement techniques

    NASA Technical Reports Server (NTRS)

    Green, W. B.

    1977-01-01

    Computer processing of digital imagery from the Viking mission to Mars is discussed, with attention given to subjective enhancement and quantitative processing. Contrast stretching and high-pass filtering techniques of subjective enhancement are described; algorithms developed to determine optimal stretch and filtering parameters are also mentioned. In addition, geometric transformations to rectify the distortion of shapes in the field of view and to alter the apparent viewpoint of the image are considered. Perhaps the most difficult problem in quantitative processing of Viking imagery was the production of accurate color representations of Orbiter and Lander camera images.

  12. Digital image processing using parallel computing based on CUDA technology

    NASA Astrophysics Data System (ADS)

    Skirnevskiy, I. P.; Pustovit, A. V.; Abdrashitova, M. O.

    2017-01-01

    This article describes expediency of using a graphics processing unit (GPU) in big data processing in the context of digital images processing. It provides a short description of a parallel computing technology and its usage in different areas, definition of the image noise and a brief overview of some noise removal algorithms. It also describes some basic requirements that should be met by certain noise removal algorithm in the projection to computer tomography. It provides comparison of the performance with and without using GPU as well as with different percentage of using CPU and GPU.

  13. Computer image processing - The Viking experience. [digital enhancement techniques

    NASA Technical Reports Server (NTRS)

    Green, W. B.

    1977-01-01

    Computer processing of digital imagery from the Viking mission to Mars is discussed, with attention given to subjective enhancement and quantitative processing. Contrast stretching and high-pass filtering techniques of subjective enhancement are described; algorithms developed to determine optimal stretch and filtering parameters are also mentioned. In addition, geometric transformations to rectify the distortion of shapes in the field of view and to alter the apparent viewpoint of the image are considered. Perhaps the most difficult problem in quantitative processing of Viking imagery was the production of accurate color representations of Orbiter and Lander camera images.

  14. Principles of image processing in digital chest radiography.

    PubMed

    Prokop, Mathias; Neitzel, Ulrich; Schaefer-Prokop, Cornelia

    2003-07-01

    Image processing has a major impact on image quality and diagnostic performance of digital chest radiographs. Goals of processing are to reduce the dynamic range of the image data to capture the full range of attenuation differences between lungs and mediastinum, to improve the modulation transfer function to optimize spatial resolution, to enhance structural contrast, and to suppress image noise. Image processing comprises look-up table operations and spatial filtering. Look-up table operations allow for automated signal normalization and arbitrary choice of image gradation. The most simple and still widely applied spatial filtering algorithms are based on unsharp masking. Various modifications were introduced for dynamic range reduction and MTF restoration. More elaborate and more effective are multi-scale frequency processing algorithms. They are based on the subdivision of an image in multiple frequency bands according to its structural composition. This allows for a wide range of image manipulations including a size-independent enhancement of low-contrast structures. Principles of the various algorithms will be explained and their impact on image appearance will be illustrated by clinical examples. Optimum and sub-optimum parameter settings are discussed and pitfalls will be explained.

  15. Digital image processing for the early localization of cancer

    NASA Astrophysics Data System (ADS)

    Kelmar, Cheryl M.

    1991-06-01

    The prognosis for cancer patients becomes much better if a tumor is diagnosed, localized and treated early, in a precancerous stage. The difficulty lies in the localization of cancerous tumors. Carcinoma in situ (CIS) refers to a tumor which is approximately 100 microns thick and one which has not penetrated through the epithelium wall or become invasive (2). A tumor of this size cannot be detected by existing techniques such as x-ray, computer tomography, magnetic resonance imaging, nuclear medicine or conventional endoscopy under white-light illumination. However, these tumors can be localized and destroyed by photodynamic diagnosis and therapy. This research shows that digital image processing and the technique of digital image ratioing contribute to photodynamic diagnosis and the early localization of cancer. A software package has been developed as a result of this research. The software package quantifies the usefulness of digital image processing for tumor localization and detectability. System parameters such as the endoscope distance and angle variations, tumor size and tumor concentration, sensitivity and specificity of the system have been tested and quantified.

  16. Digital-image processing and image analysis of glacier ice

    USGS Publications Warehouse

    Fitzpatrick, Joan J.

    2013-01-01

    This document provides a methodology for extracting grain statistics from 8-bit color and grayscale images of thin sections of glacier ice—a subset of physical properties measurements typically performed on ice cores. This type of analysis is most commonly used to characterize the evolution of ice-crystal size, shape, and intercrystalline spatial relations within a large body of ice sampled by deep ice-coring projects from which paleoclimate records will be developed. However, such information is equally useful for investigating the stress state and physical responses of ice to stresses within a glacier. The methods of analysis presented here go hand-in-hand with the analysis of ice fabrics (aggregate crystal orientations) and, when combined with fabric analysis, provide a powerful method for investigating the dynamic recrystallization and deformation behaviors of bodies of ice in motion. The procedures described in this document compose a step-by-step handbook for a specific image acquisition and data reduction system built in support of U.S. Geological Survey ice analysis projects, but the general methodology can be used with any combination of image processing and analysis software. The specific approaches in this document use the FoveaPro 4 plug-in toolset to Adobe Photoshop CS5 Extended but it can be carried out equally well, though somewhat less conveniently, with software such as the image processing toolbox in MATLAB, Image-Pro Plus, or ImageJ.

  17. Performance evaluation of image processing algorithms in digital mammography

    NASA Astrophysics Data System (ADS)

    Zanca, Federica; Van Ongeval, Chantal; Jacobs, Jurgen; Pauwels, Herman; Marchal, Guy; Bosmans, Hilde

    2008-03-01

    The purpose of the study is to evaluate the performance of different image processing algorithms in terms of representation of microcalcification clusters in digital mammograms. Clusters were simulated in clinical raw ("for processing") images. The entire dataset of images consisted of 200 normal mammograms, selected out of our clinical routine cases and acquired with a Siemens Novation DR system. In 100 of the normal images a total of 142 clusters were simulated; the remaining 100 normal mammograms served as true negative input cases. Both abnormal and normal images were processed with 5 commercially available processing algorithms: Siemens OpView1 and Siemens OpView2, Agfa Musica1, Sectra Mamea AB Sigmoid and IMS Raffaello Mammo 1.2. Five observers were asked to locate and score the cluster(s) in each image, by means of dedicated software tool. Observer performance was assessed using the JAFROC Figure of Merit. FROC curves, fitted using the IDCA method, have also been calculated. JAFROC analysis revealed significant differences among the image processing algorithms in the detection of microcalcifications clusters (p=0.0000369). Calculated average Figures of Merit are: 0.758 for Siemens OpView2, 0.747 for IMS Processing 1.2, 0.736 for Agfa Musica1 processing, 0.706 for Sectra Mamea AB Sigmoid processing and 0.703 for Siemens OpView1. This study is a first step towards a quantitative assessment of image processing in terms of cluster detection in clinical mammograms. Although we showed a significant difference among the image processing algorithms, this method does not on its own allow for a global performance ranking of the investigated algorithms.

  18. Digital image processing and analysis for activated sludge wastewater treatment.

    PubMed

    Khan, Muhammad Burhan; Lee, Xue Yong; Nisar, Humaira; Ng, Choon Aun; Yeap, Kim Ho; Malik, Aamir Saeed

    2015-01-01

    Activated sludge system is generally used in wastewater treatment plants for processing domestic influent. Conventionally the activated sludge wastewater treatment is monitored by measuring physico-chemical parameters like total suspended solids (TSSol), sludge volume index (SVI) and chemical oxygen demand (COD) etc. For the measurement, tests are conducted in the laboratory, which take many hours to give the final measurement. Digital image processing and analysis offers a better alternative not only to monitor and characterize the current state of activated sludge but also to predict the future state. The characterization by image processing and analysis is done by correlating the time evolution of parameters extracted by image analysis of floc and filaments with the physico-chemical parameters. This chapter briefly reviews the activated sludge wastewater treatment; and, procedures of image acquisition, preprocessing, segmentation and analysis in the specific context of activated sludge wastewater treatment. In the latter part additional procedures like z-stacking, image stitching are introduced for wastewater image preprocessing, which are not previously used in the context of activated sludge. Different preprocessing and segmentation techniques are proposed, along with the survey of imaging procedures reported in the literature. Finally the image analysis based morphological parameters and correlation of the parameters with regard to monitoring and prediction of activated sludge are discussed. Hence it is observed that image analysis can play a very useful role in the monitoring of activated sludge wastewater treatment plants.

  19. Study of optical techniques for the Ames unitary wind tunnel: Digital image processing, part 6

    NASA Technical Reports Server (NTRS)

    Lee, George

    1993-01-01

    A survey of digital image processing techniques and processing systems for aerodynamic images has been conducted. These images covered many types of flows and were generated by many types of flow diagnostics. These include laser vapor screens, infrared cameras, laser holographic interferometry, Schlieren, and luminescent paints. Some general digital image processing systems, imaging networks, optical sensors, and image computing chips were briefly reviewed. Possible digital imaging network systems for the Ames Unitary Wind Tunnel were explored.

  20. IMAGEP - A FORTRAN ALGORITHM FOR DIGITAL IMAGE PROCESSING

    NASA Technical Reports Server (NTRS)

    Roth, D. J.

    1994-01-01

    IMAGEP is a FORTRAN computer algorithm containing various image processing, analysis, and enhancement functions. It is a keyboard-driven program organized into nine subroutines. Within the subroutines are other routines, also, selected via keyboard. Some of the functions performed by IMAGEP include digitization, storage and retrieval of images; image enhancement by contrast expansion, addition and subtraction, magnification, inversion, and bit shifting; display and movement of cursor; display of grey level histogram of image; and display of the variation of grey level intensity as a function of image position. This algorithm has possible scientific, industrial, and biomedical applications in material flaw studies, steel and ore analysis, and pathology, respectively. IMAGEP is written in VAX FORTRAN for DEC VAX series computers running VMS. The program requires the use of a Grinnell 274 image processor which can be obtained from Mark McCloud Associates, Campbell, CA. An object library of the required GMR series software is included on the distribution media. IMAGEP requires 1Mb of RAM for execution. The standard distribution medium for this program is a 1600 BPI 9track magnetic tape in VAX FILES-11 format. It is also available on a TK50 tape cartridge in VAX FILES-11 format. This program was developed in 1991. DEC, VAX, VMS, and TK50 are trademarks of Digital Equipment Corporation.

  1. Infective endocarditis detection through SPECT/CT images digital processing

    NASA Astrophysics Data System (ADS)

    Moreno, Albino; Valdés, Raquel; Jiménez, Luis; Vallejo, Enrique; Hernández, Salvador; Soto, Gabriel

    2014-03-01

    Infective endocarditis (IE) is a difficult-to-diagnose pathology, since its manifestation in patients is highly variable. In this work, it was proposed a semiautomatic algorithm based on SPECT images digital processing for the detection of IE using a CT images volume as a spatial reference. The heart/lung rate was calculated using the SPECT images information. There were no statistically significant differences between the heart/lung rates values of a group of patients diagnosed with IE (2.62+/-0.47) and a group of healthy or control subjects (2.84+/-0.68). However, it is necessary to increase the study sample of both the individuals diagnosed with IE and the control group subjects, as well as to improve the images quality.

  2. Processing techniques for digital sonar images from GLORIA.

    USGS Publications Warehouse

    Chavez, P.S.

    1986-01-01

    Image processing techniques have been developed to handle data from one of the newest members of the remote sensing family of digital imaging systems. This paper discusses software to process data collected by the GLORIA (Geological Long Range Inclined Asdic) sonar imaging system, designed and built by the Institute of Oceanographic Sciences (IOS) in England, to correct for both geometric and radiometric distortions that exist in the original 'raw' data. Preprocessing algorithms that are GLORIA-specific include corrections for slant-range geometry, water column offset, aspect ratio distortion, changes in the ship's velocity, speckle noise, and shading problems caused by the power drop-off which occurs as a function of range.-from Author

  3. Digital image processing of crystalline specimens examined by electron microscopy.

    PubMed

    Kanaya, K

    1988-12-01

    Crystalline specimens imaged in the electron microscope are analysed using digital processing. Some principles of structural analysis using the method of Fourier decomposition are discussed. Complementary techniques, such as enhancement by gradient and Laplacian operators, have been found useful in analysing electron micrographs. The application of these techniques to some problems in Materials Science and Biology are reviewed. By selecting and phase-correcting spots in the computed diffraction pattern, it was possible to localize atoms, molecules, and their defective arrangement in evaporated gold, sputter-deposited tungsten films, and single crystals of cadmium selenide. Digital processing based on the theory of helical diffraction was used to explore the three-dimensional arrangement of molecules in cellular components of alveolar soft part sarcoma, Hirano bodies, and neurofibrillar tangles in the human brain.

  4. Liquid crystal thermography and true-colour digital image processing

    NASA Astrophysics Data System (ADS)

    Stasiek, J.; Stasiek, A.; Jewartowski, M.; Collins, M. W.

    2006-06-01

    In the last decade thermochromic liquid crystals (TLC) and true-colour digital image processing have been successfully used in non-intrusive technical, industrial and biomedical studies and applications. Thin coatings of TLCs at surfaces are utilized to obtain detailed temperature distributions and heat transfer rates for steady or transient processes. Liquid crystals also can be used to make visible the temperature and velocity fields in liquids by the simple expedient of directly mixing the liquid crystal material into the liquid (water, glycerol, glycol, and silicone oils) in very small quantities to use as thermal and hydrodynamic tracers. In biomedical situations e.g., skin diseases, breast cancer, blood circulation and other medical application, TLC and image processing are successfully used as an additional non-invasive diagnostic method especially useful for screening large groups of potential patients. The history of this technique is reviewed, principal methods and tools are described and some examples are also presented.

  5. Digital Image Processing for Noise Reduction in Medical Ultrasonics

    NASA Astrophysics Data System (ADS)

    Loupas, Thanasis

    Available from UMI in association with The British Library. Requires signed TDF. The purpose of this project was to investigate the application of digital image processing techniques as a means of reducing noise in medical ultrasonic imaging. Ultrasonic images suffer primarily from a type of acoustic noise, known as speckle, which is generally regarded as a major source of image quality degradation. The origin of speckle, its statistical properties as well as methods suggested to eliminate this artifact were reviewed. A simple model which can characterize the statistics of speckle on displays was also developed. A large number of digital noise reduction techniques was investigated. These include frame averaging techniques performed by commercially available devices and spatial filters implemented in software. Among the latter, some filters have been proposed in the scientific literature for ultrasonic, laser and microwave speckle or general noise suppression and the rest are original, developed specifically to suppress ultrasonic speckle. Particular emphasis was placed on adaptive techniques which adjust the processing performed at each point according to the local image content. In this way, they manage to suppress speckle with negligible loss of genuine image detail. Apart from preserving the diagnostically significant features of a scan another requirement a technique must satisfy before it is accepted in routine clinical practice is real-time operation. A spatial filter capable of satisfying both these requirements was designed and built in hardware using low-cost and readily available components. The possibility of incorporating all the necessary filter circuitry into a single VLSI chip was also investigated. In order to establish the effectiveness and usefulness of speckle suppression, a representative sample from the techniques examined here was applied to a large number of abdominal scans and their effect on image quality was evaluated. Finally, further

  6. Moire technique by means of digital image processing.

    PubMed

    Gasvik, K J

    1983-11-15

    Moiré technique by means of projected fringes is a suitable method for full field measurements of out-of-plane deformations and object contouring. One disadvantage in industrial applications has been the photographic process with the involved time-consuming development of the photographic film. This paper presents a new method using a TV camera and a digital image processor whereby real-time measurements of deformations and comparison of object contours are possible. Also the principles and limitations of the projected moiré method are described.

  7. Edge detection - Image-plane versus digital processing

    NASA Technical Reports Server (NTRS)

    Huck, Friedrich O.; Fales, Carl L.; Park, Stephen K.; Triplett, Judith A.

    1987-01-01

    To optimize edge detection with the familiar Laplacian-of-Gaussian operator, it has become common to implement this operator with a large digital convolution mask followed by some interpolation of the processed data to determine the zero crossings that locate edges. It is generally recognized that this large mask causes substantial blurring of fine detail. It is shown that the spatial detail can be improved by a factor of about four with either the Wiener-Laplacian-of-Gaussian filter or an image-plane processor. The Wiener-Laplacian-of-Gaussian filter minimizes the image-gathering degradations if the scene statistics are at least approximately known and also serves as an interpolator to determine the desired zero crossings directly. The image-plane processor forms the Laplacian-of-Gaussian response by properly combining the optical design of the image-gathering system with a minimal three-by-three lateral-inhibitory processing mask. This approach, which is suggested by Marr's model of early processing in human vision, also reduces data processing by about two orders of magnitude and data transmission by up to an order of magnitude.

  8. Influence of Digital Camera Errors on the Photogrammetric Image Processing

    NASA Astrophysics Data System (ADS)

    Sužiedelytė-Visockienė, Jūratė; Bručas, Domantas

    2009-01-01

    The paper deals with the calibration of digital camera Canon EOS 350D, often used for the photogrammetric 3D digitalisation and measurements of industrial and construction site objects. During the calibration data on the optical and electronic parameters, influencing the distortion of images, such as correction of the principal point, focal length of the objective, radial symmetrical and non-symmetrical distortions were obtained. The calibration was performed by means of the Tcc software implementing the polynomial of Chebichev and using a special test-field with the marks, coordinates of which are precisely known. The main task of the research - to determine how parameters of the camera calibration influence the processing of images, i. e. the creation of geometric model, the results of triangulation calculations and stereo-digitalisation. Two photogrammetric projects were created for this task. In first project the non-corrected and in the second the corrected ones, considering the optical errors of the camera obtained during the calibration, images were used. The results of analysis of the images processing is shown in the images and tables. The conclusions are given.

  9. Automation of contact lens fitting evaluation by digital image processing

    NASA Astrophysics Data System (ADS)

    Costa, Manuel F. M.; Barros, Rui; Franco, Sandra B.

    1997-08-01

    Contact lens' fitting evaluation is of critical importance in the contact lens' prescription process. For the correction of eye's refraction problems the use of contact lens' is very appealing to the user. However its prescription is far more demanding than the one of eye glasses. The fitting of a contact lens to a particular cornea must be carefully assessed in order to reduce possible user's physical miscomfort or even medical situations.The traditional way of easily checking the fitting of a contact lens is to perform a fluorescein test. The simple visual evaluation of the 'smoothness' of the color/brightness distribution of the fluorescence at the contact lens' location gives the optometrist an idea of the fitting's quality. We suggested the automation of the process simply by the substitution of the optometrist's eye by a CCD camera, and the use of appropriated simple image processing techniques. The setup and the digitalization and processing routines will be described in this communication. The processed images may then be directly analyzed by the optometrist in a faster, easier and more efficient way. However, it is also possible to perform an automated fitting evaluation by working out the information given by the image's intensity histograms for the green and blue RGB' channels.

  10. Automation of contact lens' fitting evaluation by digital image processing

    NASA Astrophysics Data System (ADS)

    da Cunha Martins Costa, M.; Barros, Rui; Franco, Sandra B.

    1997-10-01

    Contact lens' fitting evaluation is of critical importance in the contact lens' prescription process. For the correction of eye's refraction problems the use of contact lens' is very appealing to the user. However its prescription is far more demanding than the one of eye glasses. The fitting of a contact lens to a particular cornea must be carefully assessed in order to reduce possible user's physical miscomfort or even medical situations.The traditional way of easily checking the fitting of a contact lens is to perform a fluorescein test. The simple visual evaluation of the 'smoothness' of the color/brightness distribution of the fluorescence at the contact lens' location gives the optometrist an idea of the fitting's quality. We suggested the automation of the process simply by the substitution of the optometrist's eye by a CCD camera, and the use of appropriated simple image processing techniques. The setup and the digitalization and processing routines will be described in this communication. The processed images may then be directly analyzed by the optometrist in a faster, easier and more efficient way. However, it is also possible to perform an automated fitting evaluation by working out the information given by the image's intensity histograms for the green and blue RGB' channels.

  11. [Photodensitometry: microdensitometry (MD): digital image processing method (DIP)].

    PubMed

    Ohama, K; Sanada, M; Nakagawa, H

    1994-09-01

    The principles of microdensitometry (MD) and digital image processing method (DIP), as well as the application of these methods to measure bone mineral density in clinical practice, were mentioned in the report. MD and DIP assess bone mineral content and bone mineral density by analyzing relative contrast of the metacarpus II on X-ray image. However, the parameters obtained by these methods have been reported to be closely related to lumber vertebral bone mineral density and whole-body bone mineral content as measured by dual energy X-ray absorptiometry (DXA). Being easy to use, MD and DIP are adequate for the screening of osteoporosis. Once any reduction in bone mineral content or bone mineral density is shown by MD or DIP, it is recommendable to measure bone mineral density of vertebrae and femoral neck by DXA.

  12. Automated Coronal Loop Identification Using Digital Image Processing Techniques

    NASA Technical Reports Server (NTRS)

    Lee, Jong K.; Gary, G. Allen; Newman, Timothy S.

    2003-01-01

    The results of a master thesis project on a study of computer algorithms for automatic identification of optical-thin, 3-dimensional solar coronal loop centers from extreme ultraviolet and X-ray 2-dimensional images will be presented. These center splines are proxies of associated magnetic field lines. The project is pattern recognition problems in which there are no unique shapes or edges and in which photon and detector noise heavily influence the images. The study explores extraction techniques using: (1) linear feature recognition of local patterns (related to the inertia-tensor concept), (2) parametric space via the Hough transform, and (3) topological adaptive contours (snakes) that constrains curvature and continuity as possible candidates for digital loop detection schemes. We have developed synthesized images for the coronal loops to test the various loop identification algorithms. Since the topology of these solar features is dominated by the magnetic field structure, a first-order magnetic field approximation using multiple dipoles provides a priori information in the identification process. Results from both synthesized and solar images will be presented.

  13. Automated Coronal Loop Identification Using Digital Image Processing Techniques

    NASA Technical Reports Server (NTRS)

    Lee, Jong K.; Gary, G. Allen; Newman, Timothy S.

    2003-01-01

    The results of a master thesis project on a study of computer algorithms for automatic identification of optical-thin, 3-dimensional solar coronal loop centers from extreme ultraviolet and X-ray 2-dimensional images will be presented. These center splines are proxies of associated magnetic field lines. The project is pattern recognition problems in which there are no unique shapes or edges and in which photon and detector noise heavily influence the images. The study explores extraction techniques using: (1) linear feature recognition of local patterns (related to the inertia-tensor concept), (2) parametric space via the Hough transform, and (3) topological adaptive contours (snakes) that constrains curvature and continuity as possible candidates for digital loop detection schemes. We have developed synthesized images for the coronal loops to test the various loop identification algorithms. Since the topology of these solar features is dominated by the magnetic field structure, a first-order magnetic field approximation using multiple dipoles provides a priori information in the identification process. Results from both synthesized and solar images will be presented.

  14. Digital processing of side-scan sonar data with the Woods Hole image processing system software

    USGS Publications Warehouse

    Paskevich, Valerie F.

    1992-01-01

    Since 1985, the Branch of Atlantic Marine Geology has been involved in collecting, processing and digitally mosaicking high and low-resolution side-scan sonar data. Recent development of a UNIX-based image-processing software system includes a series of task specific programs for processing side-scan sonar data. This report describes the steps required to process the collected data and to produce an image that has equal along- and across-track resol

  15. GEOMETRIC PROCESSING OF DIGITAL IMAGES OF THE PLANETS.

    USGS Publications Warehouse

    Edwards, Kathleen

    1987-01-01

    New procedures and software have been developed for geometric transformations of images to support digital cartography of the planets. The procedures involve the correction of spacecraft camera orientation of each image with the use of ground control and the transformation of each image to a Sinusoidal Equal-Area map projection with an algorithm which allows the number of transformation calculations to vary as the distortion varies within the image. When the distortion is low in an area of an image, few transformation computations are required, and most pixels can be interpolated. When distortion is extreme, the location of each pixel is computed. Mosaics are made of these images and stored as digital databases.

  16. Digital Image Processing Technique for Breast Cancer Detection

    NASA Astrophysics Data System (ADS)

    Guzmán-Cabrera, R.; Guzmán-Sepúlveda, J. R.; Torres-Cisneros, M.; May-Arrioja, D. A.; Ruiz-Pinales, J.; Ibarra-Manzano, O. G.; Aviña-Cervantes, G.; Parada, A. González

    2013-09-01

    Breast cancer is the most common cause of death in women and the second leading cause of cancer deaths worldwide. Primary prevention in the early stages of the disease becomes complex as the causes remain almost unknown. However, some typical signatures of this disease, such as masses and microcalcifications appearing on mammograms, can be used to improve early diagnostic techniques, which is critical for women’s quality of life. X-ray mammography is the main test used for screening and early diagnosis, and its analysis and processing are the keys to improving breast cancer prognosis. As masses and benign glandular tissue typically appear with low contrast and often very blurred, several computer-aided diagnosis schemes have been developed to support radiologists and internists in their diagnosis. In this article, an approach is proposed to effectively analyze digital mammograms based on texture segmentation for the detection of early stage tumors. The proposed algorithm was tested over several images taken from the digital database for screening mammography for cancer research and diagnosis, and it was found to be absolutely suitable to distinguish masses and microcalcifications from the background tissue using morphological operators and then extract them through machine learning techniques and a clustering algorithm for intensity-based segmentation.

  17. Microcomputer-based digital image processing - A tutorial package for exploration geologists

    NASA Technical Reports Server (NTRS)

    Harrington, J. A., Jr.; Cartin, K. F.

    1985-01-01

    An Apple II microcomputer-based software package for analysis of digital data developed at the University of Oklahoma, the Digital Image Analysis System (DIAS), provides a relatively low-cost, portable alternative to large, dedicated minicomputers for digital image processing education. Digital processing techniques for analysis of Landsat MSS data and a series of tutorial exercises for exploration geologists are described and evaluated. DIAS allows in-house training that does not interfere with computer-based prospect analysis objectives.

  18. Microcomputer-based digital image processing - A tutorial package for exploration geologists

    NASA Technical Reports Server (NTRS)

    Harrington, J. A., Jr.; Cartin, K. F.

    1985-01-01

    An Apple II microcomputer-based software package for analysis of digital data developed at the University of Oklahoma, the Digital Image Analysis System (DIAS), provides a relatively low-cost, portable alternative to large, dedicated minicomputers for digital image processing education. Digital processing techniques for analysis of Landsat MSS data and a series of tutorial exercises for exploration geologists are described and evaluated. DIAS allows in-house training that does not interfere with computer-based prospect analysis objectives.

  19. Performance of the SIR-B digital image processing subsystem

    NASA Technical Reports Server (NTRS)

    Curlander, J. C.

    1986-01-01

    A ground-based system to generate digital SAR image products has been developed and implemented in support of the SIR-B mission. This system is designed to achieve the maximum throughput while meeting strict image fidelity criteria. Its capabilities include: automated radiometric and geometric correction of the output imagery; high-precision absolute location without tiepoint registration; filtering of the raw data to remove spurious signals from alien radars; and automated catologing to maintain a full set of radar and image production facility in support of the SIR-B science investigators routinely produces over 80 image frames per week.

  20. Performance of the SIR-B digital image processing subsystem

    NASA Technical Reports Server (NTRS)

    Curlander, J. C.

    1986-01-01

    A ground-based system to generate digital SAR image products has been developed and implemented in support of the SIR-B mission. This system is designed to achieve the maximum throughput while meeting strict image fidelity criteria. Its capabilities include: automated radiometric and geometric correction of the output imagery; high-precision absolute location without tiepoint registration; filtering of the raw data to remove spurious signals from alien radars; and automated catologing to maintain a full set of radar and image production facility in support of the SIR-B science investigators routinely produces over 80 image frames per week.

  1. The effects of gray scale image processing on digital mammography interpretation performance.

    PubMed

    Cole, Elodia B; Pisano, Etta D; Zeng, Donglin; Muller, Keith; Aylward, Stephen R; Park, Sungwook; Kuzmiak, Cherie; Koomen, Marcia; Pavic, Dag; Walsh, Ruth; Baker, Jay; Gimenez, Edgardo I; Freimanis, Rita

    2005-05-01

    To determine the effects of three image-processing algorithms on diagnostic accuracy of digital mammography in comparison with conventional screen-film mammography. A total of 201 cases consisting of nonprocessed soft copy versions of the digital mammograms acquired from GE, Fischer, and Trex digital mammography systems (1997-1999) and conventional screen-film mammograms of the same patients were interpreted by nine radiologists. The raw digital data were processed with each of three different image-processing algorithms creating three presentations-manufacturer's default (applied and laser printed to film by each of the manufacturers), MUSICA, and PLAHE-were presented in soft copy display. There were three radiologists per presentation. Area under the receiver operating characteristic curve for GE digital mass cases was worse than screen-film for all digital presentations. The area under the receiver operating characteristic for Trex digital mass cases was better, but only with images processed with the manufacturer's default algorithm. Sensitivity for GE digital mass cases was worse than screen film for all digital presentations. Specificity for Fischer digital calcifications cases was worse than screen film for images processed in default and PLAHE algorithms. Specificity for Trex digital calcifications cases was worse than screen film for images processed with MUSICA. Specific image-processing algorithms may be necessary for optimal presentation for interpretation based on machine and lesion type.

  2. Identification and Quantification Soil Redoximorphic Features by Digital Image Processing

    USDA-ARS?s Scientific Manuscript database

    Soil redoximorphic features (SRFs) have provided scientists and land managers with insight into relative soil moisture for approximately 60 years. The overall objective of this study was to develop a new method of SRF identification and quantification from soil cores using a digital camera and imag...

  3. Parallel Digital Watermarking Process on Ultrasound Medical Images in Multicores Environment

    PubMed Central

    Khor, Hui Liang; Liew, Siau-Chuin; Zain, Jasni Mohd.

    2016-01-01

    With the advancement of technology in communication network, it facilitated digital medical images transmitted to healthcare professionals via internal network or public network (e.g., Internet), but it also exposes the transmitted digital medical images to the security threats, such as images tampering or inserting false data in the images, which may cause an inaccurate diagnosis and treatment. Medical image distortion is not to be tolerated for diagnosis purposes; thus a digital watermarking on medical image is introduced. So far most of the watermarking research has been done on single frame medical image which is impractical in the real environment. In this paper, a digital watermarking on multiframes medical images is proposed. In order to speed up multiframes watermarking processing time, a parallel watermarking processing on medical images processing by utilizing multicores technology is introduced. An experiment result has shown that elapsed time on parallel watermarking processing is much shorter than sequential watermarking processing. PMID:26981111

  4. Recent developments at JPL in the application of digital image processing techniques to astronomical images

    NASA Technical Reports Server (NTRS)

    Lorre, J. J.; Lynn, D. J.; Benton, W. D.

    1976-01-01

    Several techniques of a digital image-processing nature are illustrated which have proved useful in visual analysis of astronomical pictorial data. Processed digital scans of photographic plates of Stephans Quintet and NGC 4151 are used as examples to show how faint nebulosity is enhanced by high-pass filtering, how foreground stars are suppressed by linear interpolation, and how relative color differences between two images recorded on plates with different spectral sensitivities can be revealed by generating ratio images. Analyses are outlined which are intended to compensate partially for the blurring effects of the atmosphere on images of Stephans Quintet and to obtain more detailed information about Saturn's ring structure from low- and high-resolution scans of the planet and its ring system. The employment of a correlation picture to determine the tilt angle of an average spectral line in a low-quality spectrum is demonstrated for a section of the spectrum of Uranus.

  5. Centralized Digital Picture Processing System For Cardiac Imaging

    NASA Astrophysics Data System (ADS)

    LeFree, M. T.; Vogel, R. A.

    1982-01-01

    We have designed and implemented a system for the centralized acquisition, display, analysis and archiving of diagnostic cardiac medical images from x-ray fluoroscopy, two-dimensional ultrasonography and nuclear scintigraphy. Centered around a DLC PUP 11/34 minicomputer with an existing gamma camera interface, we have added a closed-circuit television system with a 256x512x8-bit video digitizer and image display controller to interface the video output of the fluoroscope and ultrasonograph. A video disc recorder (under computer control) is used as an input and playback buffer, allowing for data transfer to and from digital disc drives. Thus, real-time video digitization is possible for up to ten seconds of incoming RS-170-compatible video. The digitizer separates video fields at real-time into two 256x256x8-bit refresh memories, providing 60Hz temporal resolution. Generally, however, we choose to record at non-real-time rates to encompass more than ten seconds. In addition to I/O software controlling data acquisition ana playback, we have developed a versatile data analysis package (offering such capabilities as image algebra, Fourier analysis and convolutional filtering), as well as interactive data reduction subroutines (such as region-of-interest definition, profile plotting and regional extraction of statistical and probabilistic information). We have found the system useful for standard cardiac image analysis, for simultaneous display of images from the three modalities, for picture storage and retrieval, and as a research tool. future plans include the addition of intelligent terminals at each modality and progression to a 32-bit machine for the central processor.

  6. Digital signal and image processing in echocardiography. The American Society of Echocardiography.

    PubMed

    Skorton, D J; Collins, S M; Garcia, E; Geiser, E A; Hillard, W; Koppes, W; Linker, D; Schwartz, G

    1985-12-01

    Digital signal and image processing techniques are acquiring an increasingly important role in the generation and analysis of cardiac images. This is particularly true of 2D echocardiography, in which image acquisition, manipulation, and storage within the echocardiograph, as well as quantitative analysis of echocardiographic data by means of "off-line" systems, depend upon digital techniques. The increasing role of computers in echocardiography makes it essential that echocardiographers and technologists understand the basic principles of digital techniques applied to echocardiographic instrumentation and data analysis. In this article, we have discussed digital techniques as applied to image generation (digital scan conversion, preprocessing, and postprocessing) as well as to the analysis of image data (computer-assisted border detection, 3D reconstruction, tissue characterization, and contrast echocardiography); a general introduction to off-line analysis systems was also given. Experience with other cardiac imaging methods indicates that digital techniques will likely play a dominant role in the future of echocardiographic imaging.

  7. [Studies on digital watermark embedding intensity against image processing and image deterioration].

    PubMed

    Nishio, Masato; Ando, Yutaka; Tsukamoto, Nobuhiro; Kawashima, Hironao

    2004-04-01

    In order to apply digital watermarking to medical imaging, it is required to find a trade-off between strength of watermark embedding and deterioration of image quality. In this study, watermarks were embedded in 4 types of modality images to determine the correlation among the watermarking strength, robustness against image processing, and image deterioration due to embedding. The results demonstrated that watermarks which were embedded by the least significant bit insertion method became unable to be detected and recognized on image processing even if the watermarks were embedded with such strength that could cause image deterioration. On the other hand, watermarks embedded by the Discrete Cosine Transform were clearly detected and recognized even after image processing regardless of the embedding strength. The maximum level of embedding strength that will not affect diagnosis differed depending on the type of modality. It is expected that embedding the patient information together with the facility information as watermarks will help maintain the patient information, prevent mix-ups of the images, and identify the test performing facilities. The concurrent use of watermarking less resistant to image processing makes it possible to detect whether any image processing has been performed or not.

  8. Digital image processing software system using an array processor

    SciTech Connect

    Sherwood, R.J.; Portnoff, M.R.; Journeay, C.H.; Twogood, R.E.

    1981-03-10

    A versatile array processor-based system for general-purpose image processing was developed. At the heart of this system is an extensive, flexible software package that incorporates the array processor for effective interactive image processing. The software system is described in detail, and its application to a diverse set of applications at LLNL is briefly discussed. 4 figures, 1 table.

  9. APPLEPIPS /Apple Personal Image Processing System/ - An interactive digital image processing system for the Apple II microcomputer

    NASA Technical Reports Server (NTRS)

    Masuoka, E.; Rose, J.; Quattromani, M.

    1981-01-01

    Recent developments related to microprocessor-based personal computers have made low-cost digital image processing systems a reality. Image analysis systems built around these microcomputers provide color image displays for images as large as 256 by 240 pixels in sixteen colors. Descriptive statistics can be computed for portions of an image, and supervised image classification can be obtained. The systems support Basic, Fortran, Pascal, and assembler language. A description is provided of a system which is representative of the new microprocessor-based image processing systems currently on the market. While small systems may never be truly independent of larger mainframes, because they lack 9-track tape drives, the independent processing power of the microcomputers will help alleviate some of the turn-around time problems associated with image analysis and display on the larger multiuser systems.

  10. Enhancing the Teaching of Digital Processing of Remote Sensing Image Course through Geospatial Web Processing Services

    NASA Astrophysics Data System (ADS)

    di, L.; Deng, M.

    2010-12-01

    Remote sensing (RS) is an essential method to collect data for Earth science research. Huge amount of remote sensing data, most of them in the image form, have been acquired. Almost all geography departments in the world offer courses in digital processing of remote sensing images. Such courses place emphasis on how to digitally process large amount of multi-source images for solving real world problems. However, due to the diversity and complexity of RS images and the shortcomings of current data and processing infrastructure, obstacles for effectively teaching such courses still remain. The major obstacles include 1) difficulties in finding, accessing, integrating and using massive RS images by students and educators, and 2) inadequate processing functions and computing facilities for students to freely explore the massive data. Recent development in geospatial Web processing service systems, which make massive data, computing powers, and processing capabilities to average Internet users anywhere in the world, promises the removal of the obstacles. The GeoBrain system developed by CSISS is an example of such systems. All functions available in GRASS Open Source GIS have been implemented as Web services in GeoBrain. Petabytes of remote sensing images in NASA data centers, the USGS Landsat data archive, and NOAA CLASS are accessible transparently and processable through GeoBrain. The GeoBrain system is operated on a high performance cluster server with large disk storage and fast Internet connection. All GeoBrain capabilities can be accessed by any Internet-connected Web browser. Dozens of universities have used GeoBrain as an ideal platform to support data-intensive remote sensing education. This presentation gives a specific example of using GeoBrain geoprocessing services to enhance the teaching of GGS 588, Digital Remote Sensing taught at the Department of Geography and Geoinformation Science, George Mason University. The course uses the textbook "Introductory

  11. Qualitative and quantitative interpretation of SEM image using digital image processing.

    PubMed

    Saladra, Dawid; Kopernik, Magdalena

    2016-10-01

    The aim of the this study is improvement of qualitative and quantitative analysis of scanning electron microscope micrographs by development of computer program, which enables automatic crack analysis of scanning electron microscopy (SEM) micrographs. Micromechanical tests of pneumatic ventricular assist devices result in a large number of micrographs. Therefore, the analysis must be automatic. Tests for athrombogenic titanium nitride/gold coatings deposited on polymeric substrates (Bionate II) are performed. These tests include microshear, microtension and fatigue analysis. Anisotropic surface defects observed in the SEM micrographs require support for qualitative and quantitative interpretation. Improvement of qualitative analysis of scanning electron microscope images was achieved by a set of computational tools that includes binarization, simplified expanding, expanding, simple image statistic thresholding, the filters Laplacian 1, and Laplacian 2, Otsu and reverse binarization. Several modifications of the known image processing techniques and combinations of the selected image processing techniques were applied. The introduced quantitative analysis of digital scanning electron microscope images enables computation of stereological parameters such as area, crack angle, crack length, and total crack length per unit area. This study also compares the functionality of the developed computer program of digital image processing with existing applications. The described pre- and postprocessing may be helpful in scanning electron microscopy and transmission electron microscopy surface investigations. © 2016 The Authors Journal of Microscopy © 2016 Royal Microscopical Society.

  12. Interaction of image noise, spatial resolution, and low contrast fine detail preservation in digital image processing

    NASA Astrophysics Data System (ADS)

    Artmann, Uwe; Wueller, Dietmar

    2009-01-01

    We present a method to improve the validity of noise and resolution measurements on digital cameras. If non-linear adaptive noise reduction is part of the signal processing in the camera, the measurement results for image noise and spatial resolution can be good, while the image quality is low due to the loss of fine details and a watercolor like appearance of the image. To improve the correlation between objective measurement and subjective image quality we propose to supplement the standard test methods with an additional measurement of the texture preserving capabilities of the camera. The proposed method uses a test target showing white Gaussian noise. The camera under test reproduces this target and the image is analyzed. We propose to use the kurtosis of the derivative of the image as a metric for the texture preservation of the camera. Kurtosis is a statistical measure for the closeness of a distribution compared to the Gaussian distribution. It can be shown, that the distribution of digital values in the derivative of the image showing the chart becomes the more leptokurtic (increased kurtosis) the stronger the noise reduction has an impact on the image.

  13. Implementation of real-time digital endoscopic image processing system

    NASA Astrophysics Data System (ADS)

    Song, Chul Gyu; Lee, Young Mook; Lee, Sang Min; Kim, Won Ky; Lee, Jae Ho; Lee, Myoung Ho

    1997-10-01

    Endoscopy has become a crucial diagnostic and therapeutic procedure in clinical areas. Over the past four years, we have developed a computerized system to record and store clinical data pertaining to endoscopic surgery of laparascopic cholecystectomy, pelviscopic endometriosis, and surgical arthroscopy. In this study, we developed a computer system, which is composed of a frame grabber, a sound board, a VCR control board, a LAN card and EDMS. Also, computer system controls peripheral instruments such as a color video printer, a video cassette recorder, and endoscopic input/output signals. Digital endoscopic data management system is based on open architecture and a set of widely available industry standards; namely Microsoft Windows as an operating system, TCP/IP as a network protocol and a time sequential database that handles both images and speech. For the purpose of data storage, we used MOD and CD- R. Digital endoscopic system was designed to be able to store, recreate, change, and compress signals and medical images. Computerized endoscopy enables us to generate and manipulate the original visual document, making it accessible to a virtually unlimited number of physicians.

  14. Nonlinear color-image decomposition for image processing of a digital color camera

    NASA Astrophysics Data System (ADS)

    Saito, Takahiro; Aizawa, Haruya; Yamada, Daisuke; Komatsu, Takashi

    2009-01-01

    This paper extends the BV (Bounded Variation) - G and/or the BV-L1 variational nonlinear image-decomposition approaches, which are considered to be useful for image processing of a digital color camera, to genuine color-image decomposition approaches. For utilizing inter-channel color cross-correlations, this paper first introduces TV (Total Variation) norms of color differences and TV norms of color sums into the BV-G and/or BV-L1 energy functionals, and then derives denoising-type decomposition-algorithms with an over-complete wavelet transform, through applying the Besov-norm approximation to the variational problems. Our methods decompose a noisy color image without producing undesirable low-frequency colored artifacts in its separated BV-component, and they achieve desirable high-quality color-image decomposition, which is very robust against colored random noise.

  15. Automatic calculation of tree diameter from stereoscopic image pairs using digital image processing.

    PubMed

    Yi, Faliu; Moon, Inkyu

    2012-06-20

    Automatic operations play an important role in societies by saving time and improving efficiency. In this paper, we apply the digital image processing method to the field of lumbering to automatically calculate tree diameters in order to reduce culler work and enable a third party to verify tree diameters. To calculate the cross-sectional diameter of a tree, the image was first segmented by the marker-controlled watershed transform algorithm based on the hue saturation intensity (HSI) color model. Then, the tree diameter was obtained by measuring the area of every isolated region in the segmented image. Finally, the true diameter was calculated by multiplying the diameter computed in the image and the scale, which was derived from the baseline and disparity of correspondence points from stereoscopic image pairs captured by rectified configuration cameras.

  16. IBIS - A geographic information system based on digital image processing and image raster datatype

    NASA Technical Reports Server (NTRS)

    Bryant, N. A.; Zobrist, A. L.

    1976-01-01

    IBIS (Image Based Information System) is a geographic information system which makes use of digital image processing techniques to interface existing geocoded data sets and information management systems with thematic maps and remotely sensed imagery. The basic premise is that geocoded data sets can be referenced to a raster scan that is equivalent to a grid cell data set. The first applications (St. Tammany Parish, Louisiana, and Los Angeles County) have been restricted to the design of a land resource inventory and analysis system. It is thought that the algorithms and the hardware interfaces developed will be readily applicable to other Landsat imagery.

  17. IBIS - A geographic information system based on digital image processing and image raster datatype

    NASA Technical Reports Server (NTRS)

    Bryant, N. A.; Zobrist, A. L.

    1976-01-01

    IBIS (Image Based Information System) is a geographic information system which makes use of digital image processing techniques to interface existing geocoded data sets and information management systems with thematic maps and remotely sensed imagery. The basic premise is that geocoded data sets can be referenced to a raster scan that is equivalent to a grid cell data set. The first applications (St. Tammany Parish, Louisiana, and Los Angeles County) have been restricted to the design of a land resource inventory and analysis system. It is thought that the algorithms and the hardware interfaces developed will be readily applicable to other Landsat imagery.

  18. Digital Image Processing Techniques to Create Attractive Astronomical Images from Research Data

    NASA Astrophysics Data System (ADS)

    Rector, T. A.; Levay, Z.; Frattare, L. M.; English, J.; Pummill, K.

    2003-12-01

    The quality of modern astronomical data, the power of modern computers and the agility of current image processing software enable the creation of high-quality images in a purely digital form that rival the quality of traditional photographic astronomical images. The combination of these technological advancements has created a new ability to make color astronomical images. And in many ways, it has led to a new philosophy towards how to create them. We present a practical guide to generate astronomical images from research data by using powerful image processing programs. These programs use a layering metaphor that allows an unlimited number of astronomical datasets to be combined in any desired color scheme, creating an immense parameter space to be explored using an iterative approach. Several examples of image creation are presented. We also present a philosophy on how to use color and composition to create images that simultaneously highlight the scientific detail within an image and are aesthetically appealing. We advocate an approach that uses visual grammar, defined as the elements which affect the interpretation of an image, to maximize the richness and detail in an image while maintaining scientific accuracy. By properly using visual grammar, one can imply qualities that a two-dimensional image intrinsically cannot show, such as depth, motion and energy. In addition, composition can be used to engage the viewer and keep him or her interested for a longer period of time. The effective use of these techniques can result in a striking image that will effectively convey the science within the image, to scientists and to the public.

  19. Digital Image Processing Techniques to Create Attractive Astronomical Images from Research Data

    NASA Astrophysics Data System (ADS)

    Rector, T. A.; Levay, Z.; Frattare, L.; English, J.; Pu'uohau-Pummill, K.

    2004-05-01

    The quality of modern astronomical data, the power of modern computers and the agility of current image processing software enable the creation of high-quality images in a purely digital form that rival the quality of traditional photographic astronomical images. The combination of these technological advancements has created a new ability to make color astronomical images. And in many ways, it has led to a new philosophy towards how to create them. We present a practical guide to generate astronomical images from research data by using powerful image processing programs. These programs use a layering metaphor that allows an unlimited number of astronomical datasets to be combined in any desired color scheme, creating an immense parameter space to be explored using an iterative approach. Several examples of image creation are presented. We also present a philosophy on how to use color and composition to create images that simultaneously highlight the scientific detail within an image and are aesthetically appealing. We advocate an approach that uses visual grammar, defined as the elements which affect the interpretation of an image, to maximize the richness and detail in an image while maintaining scientific accuracy. By properly using visual grammar, one can imply qualities that a two-dimensional image intrinsically cannot show, such as depth, motion and energy. In addition, composition can be used to engage the viewer and keep him or her interested for a longer period of time. The effective use of these techniques can result in a striking image that will effectively convey the science within the image, to scientists and to the public.

  20. Digital image processing on a small computer system

    NASA Technical Reports Server (NTRS)

    Danielson, R.

    1981-01-01

    A minicomputer-based image processing facility provides a relatively low-cost entry point for education about image analysis applications in remote sensing. While a minicomputer has sufficient processing power to produce results quite rapidly for low volumes of small images, it does not have sufficient power to perform CPU- or 1/0-bound tasks on large images. A system equipped with a display terminal is ideally suited for interactive tasks. Software procurement is a limiting factor for most end users, and software availability may well be the overriding consideration in selecting a particular hardware configuration. The hardware chosen should be selected to be compatible with the software and with concern for future expansion.

  1. Modular Scanning Confocal Microscope with Digital Image Processing

    PubMed Central

    McCluskey, Matthew D.

    2016-01-01

    In conventional confocal microscopy, a physical pinhole is placed at the image plane prior to the detector to limit the observation volume. In this work, we present a modular design of a scanning confocal microscope which uses a CCD camera to replace the physical pinhole for materials science applications. Experimental scans were performed on a microscope resolution target, a semiconductor chip carrier, and a piece of etched silicon wafer. The data collected by the CCD were processed to yield images of the specimen. By selecting effective pixels in the recorded CCD images, a virtual pinhole is created. By analyzing the image moments of the imaging data, a lateral resolution enhancement is achieved by using a 20 × / NA = 0.4 microscope objective at 532 nm laser wavelength. PMID:27829052

  2. Modular Scanning Confocal Microscope with Digital Image Processing.

    PubMed

    Ye, Xianjun; McCluskey, Matthew D

    2016-01-01

    In conventional confocal microscopy, a physical pinhole is placed at the image plane prior to the detector to limit the observation volume. In this work, we present a modular design of a scanning confocal microscope which uses a CCD camera to replace the physical pinhole for materials science applications. Experimental scans were performed on a microscope resolution target, a semiconductor chip carrier, and a piece of etched silicon wafer. The data collected by the CCD were processed to yield images of the specimen. By selecting effective pixels in the recorded CCD images, a virtual pinhole is created. By analyzing the image moments of the imaging data, a lateral resolution enhancement is achieved by using a 20 × / NA = 0.4 microscope objective at 532 nm laser wavelength.

  3. Processing, mosaicking and management of the Monterey Bay digital sidescan-sonar images

    USGS Publications Warehouse

    Chavez, P.S.; Isbrecht, J.; Galanis, P.; Gabel, G.L.; Sides, S.C.; Soltesz, D.L.; Ross, S.L.; Velasco, M.G.

    2002-01-01

    Sidescan-sonar imaging systems with digital capabilities have now been available for approximately 20 years. In this paper we present several of the various digital image processing techniques developed by the U.S. Geological Survey (USGS) and used to apply intensity/radiometric and geometric corrections, as well as enhance and digitally mosaic, sidescan-sonar images of the Monterey Bay region. New software run by a WWW server was designed and implemented to allow very large image data sets, such as the digital mosaic, to be easily viewed interactively, including the ability to roam throughout the digital mosaic at the web site in either compressed or full 1-m resolution. The processing is separated into the two different stages: preprocessing and information extraction. In the preprocessing stage, sensor-specific algorithms are applied to correct for both geometric and intensity/radiometric distortions introduced by the sensor. This is followed by digital mosaicking of the track-line strips into quadrangle format which can be used as input to either visual or digital image analysis and interpretation. An automatic seam removal procedure was used in combination with an interactive digital feathering/stenciling procedure to help minimize tone or seam matching problems between image strips from adjacent track-lines. The sidescan-sonar image processing package is part of the USGS Mini Image Processing System (MIPS) and has been designed to process data collected by any 'generic' digital sidescan-sonar imaging system. The USGS MIPS software, developed over the last 20 years as a public domain package, is available on the WWW at: http://terraweb.wr.usgs.gov/trs/software.html.

  4. Developing an undergraduate geography course on digital image processing of remotely sensed data

    NASA Technical Reports Server (NTRS)

    Baumann, P. R.

    1981-01-01

    Problems relating to the development of a digital image processing course in an undergraduate geography environment is discussed. Computer resource requirements, course prerequisites, and the size of the study area are addressed.

  5. Developing an undergraduate geography course on digital image processing of remotely sensed data

    NASA Technical Reports Server (NTRS)

    Baumann, P. R.

    1981-01-01

    Problems relating to the development of a digital image processing course in an undergraduate geography environment is discussed. Computer resource requirements, course prerequisites, and the size of the study area are addressed.

  6. Application of digital image processing techniques to astronomical imagery 1978

    NASA Technical Reports Server (NTRS)

    Lorre, J. J.

    1978-01-01

    Techniques for using image processing in astronomy are identified and developed for the following: (1) geometric and radiometric decalibration of vidicon-acquired spectra, (2) automatic identification and segregation of stars from galaxies; and (3) display of multiband radio maps in compact and meaningful formats. Examples are presented of these techniques applied to a variety of objects.

  7. Development of digital processing method of microfocus X-ray images

    NASA Astrophysics Data System (ADS)

    Staroverov, N. E.; Kholopova, E. D.; Gryaznov, A. Yu; Zhamova, K. K.

    2017-02-01

    The article describes the basic methods of X-ray images digital processing. Also in the article is proposed method for background image aligning based on modeling of distorting function and subtracting it from the image. As a result is proposed the improved algorithm for locally adaptive median filtering for which has been carried out the effectiveness experimental verification.

  8. Application of digital image processing techniques to astronomical imagery, 1979

    NASA Technical Reports Server (NTRS)

    Lorre, J. J.

    1979-01-01

    Several areas of applications of image processing to astronomy were identified and discussed. These areas include: (1) deconvolution for atmospheric seeing compensation; a comparison between maximum entropy and conventional Wiener algorithms; (2) polarization in galaxies from photographic plates; (3) time changes in M87 and methods of displaying these changes; (4) comparing emission line images in planetary nebulae; and (5) log intensity, hue saturation intensity, and principal component color enhancements of M82. Examples are presented of these techniques applied to a variety of objects.

  9. Digital Processing of Medical Images Obtained by a Si Microstrips Detector

    SciTech Connect

    Diaz, Claudia C.; Montano, Luis M.; Fontaine, Marcos; Leyva, Antonio

    2006-09-08

    We studied the capability of Matlab in digital processing of breast tissues images with microcalcifications. We obtained digital images of different byopsies through a Bede X-ray tube, fixed at 20 kV and 1 mA. Radiation exposition time was varied. The byopsies were placed between a 120{mu}m collimator and a 128 strips detector, which was used to measure the absorption of X rays in the tissue. Matlab allowed the manipulation of digital images, and this software was intended to improve the identification of microcalcifications in breast tissues.

  10. [Evaluating the maturity of IT-supported clinical imaging and diagnosis using the Digital Imaging Adoption Model : Are your clinical imaging processes ready for the digital era?

    PubMed

    Studzinski, J

    2017-06-01

    The Digital Imaging Adoption Model (DIAM) has been jointly developed by HIMSS Analytics and the European Society of Radiology (ESR). It helps evaluate the maturity of IT-supported processes in medical imaging, particularly in radiology. This eight-stage maturity model drives your organisational, strategic and tactical alignment towards imaging-IT planning. The key audience for the model comprises hospitals with imaging centers, as well as external imaging centers that collaborate with hospitals. The assessment focuses on different dimensions relevant to digital imaging, such as software infrastructure and usage, workflow security, clinical documentation and decision support, data exchange and analytical capabilities. With its standardised approach, it enables regional, national and international benchmarking. All DIAM participants receive a structured report that can be used as a basis for presenting, e.g. budget planning and investment decisions at management level.

  11. Digital processing of the Mariner 10 images of Venus and Mercury

    NASA Technical Reports Server (NTRS)

    Soha, J. M.; Lynn, D. J.; Mosher, J. A.; Elliot, D. A.

    1977-01-01

    An extensive effort was devoted to the digital processing of the Mariner 10 images of Venus and Mercury at the Image Processing Laboratory of the Jet Propulsion Laboratory. This effort was designed to optimize the display of the considerable quantity of information contained in the images. Several image restoration, enhancement, and transformation procedures were applied; examples of these techniques are included. A particular task was the construction of large mosaics which characterize the surface of Mercury and the atmospheric structure of Venus.

  12. Digital Image Manipulation, Analysis and Processing Systems (DIMAPS) A research-oriented, experimental image-processing system

    NASA Astrophysics Data System (ADS)

    Dave, J. V.

    1985-04-01

    The acronym DIMAPS stands for the group of experimental Digital Image Manipulation, Analysis and Processing Systems developed at the IBM Scientific Center in Palo Alto, California. These are FORTRAN-based, dialog-driven, fully interactive programs for the IBM 4341 (or equivalent) computer running under VM/CMS or MVS/TSO. The work station consists of three screens (alphanumeric, high-resolution vector graphics, and high-resolution color display), plus a digitizing graphics tablet, cursor controllers, keyboards, and hard copy devices. The DIMAPS software is 98% FORTRAN, thus facilitating maintenance, system growth, and transportability. The original DIMAPS and its modified versions contain functions for the generation, display and comparison of multiband images, and for the quantitative as well as graphic display of data in a selected section of the image under study. Several functions for performing data modification and/or analysis tasks are also included. Some high-level image processing and analysis functions such as the generation of shaded-relief images, unsupervised multispectral classification, scene-to-scene or map-to-scene registration of multiband digital data, extraction of texture information using a two-dimensional Fourier transform of the band data, and reduction of random noise from multiband data using phase agreement among their Fourier coefficients, were developed as adjuncts to DIMAPS.

  13. Digital image manipulation, analysis and processing systems (DIMAPS) - A research-oriented, experimental image-processing system

    NASA Astrophysics Data System (ADS)

    Dave, J. V.

    1985-12-01

    Digital Image Manipulation, Analysis and Processing Systems DIMAPS are FORTRAN-based, dialog-driven, fully interactive programs for the IBM 4341 (or equivalent) computer running under VM/CMS or MVS/TSO. The work station consists of three screens (alphanumeric, high-resolution vector graphics, and high-resolution color display), together with a digitizing graphics tablet, cursor controllers, keyboards, and hard copy devices. The DIMAPS software is 98-percent FORTRAN, thus facilitating maintenance, system growth, and transportability. The original DIMAPS and its modified versions contain functions for the generation, display and comparison of multiband images, and for the quantitative as well as graphic display of data in a selected section of the image under study. Several functions for performing data modification and/or analysis tasks are also included. Some high-level image processing and analysis functions such as the generation of shaded-relief images, unsupervised multispectral classification, scene-to-scene or map-to-scene registration of multiband digital data, extraction of texture information using a two-dimensional Fourier transform of the band data, and reduction of random noise from multiband data using phase agreement among their Fourier coefficients, were developed as adjuncts to DIMAPS.

  14. The effect of image processing on the detection of cancers in digital mammography.

    PubMed

    Warren, Lucy M; Given-Wilson, Rosalind M; Wallis, Matthew G; Cooke, Julie; Halling-Brown, Mark D; Mackenzie, Alistair; Chakraborty, Dev P; Bosmans, Hilde; Dance, David R; Young, Kenneth C

    2014-08-01

    OBJECTIVE. The objective of our study was to investigate the effect of image processing on the detection of cancers in digital mammography images. MATERIALS AND METHODS. Two hundred seventy pairs of breast images (both breasts, one view) were collected from eight systems using Hologic amorphous selenium detectors: 80 image pairs showed breasts containing subtle malignant masses; 30 image pairs, biopsy-proven benign lesions; 80 image pairs, simulated calcification clusters; and 80 image pairs, no cancer (normal). The 270 image pairs were processed with three types of image processing: standard (full enhancement), low contrast (intermediate enhancement), and pseudo-film-screen (no enhancement). Seven experienced observers inspected the images, locating and rating regions they suspected to be cancer for likelihood of malignancy. The results were analyzed using a jackknife-alternative free-response receiver operating characteristic (JAFROC) analysis. RESULTS. The detection of calcification clusters was significantly affected by the type of image processing: The JAFROC figure of merit (FOM) decreased from 0.65 with standard image processing to 0.63 with low-contrast image processing (p = 0.04) and from 0.65 with standard image processing to 0.61 with film-screen image processing (p = 0.0005). The detection of noncalcification cancers was not significantly different among the image-processing types investigated (p > 0.40). CONCLUSION. These results suggest that image processing has a significant impact on the detection of calcification clusters in digital mammography. For the three image-processing versions and the system investigated, standard image processing was optimal for the detection of calcification clusters. The effect on cancer detection should be considered when selecting the type of image processing in the future.

  15. The teaching of computer programming and digital image processing in radiography.

    PubMed

    Allan, G L; Zylinski, J

    1998-06-01

    The increased use of digital processing techniques in Medical Radiations imaging modalities, along with the rapid advance in information technology has resulted in a significant change in the delivery of radiographic teaching programs. This paper details a methodology used to concurrently educate radiographers in both computer programming and image processing. The students learn to program in visual basic applications (VBA), and the programming skills are contextualised by requiring the students to write a digital subtraction angiography (DSA) package. Program code generation and image presentation interface is undertaken by the spreadsheet Microsoft Excel. The user-friendly nature of this common interface enables all students to readily begin program creation. The teaching of programming and image processing skills by this method may be readily generalised to other vocational fields where digital image manipulation is a professional requirement.

  16. Digital Image Processing Applied To Problems In Art And Archaeology

    NASA Astrophysics Data System (ADS)

    Asmus, John F.; Katz, Norman P.

    1988-12-01

    Many of the images encountered during scholarly studies in the fields of art and archaeology have deteriorated through the effects of time. The Ice-Age rock art of the now-closed caves near Lascaux are prime examples of this fate. However, faint and subtle details of these can be exceedingly important as some theories suggest that the designs are computers or calendars pertaining to astronomical cycles as well as seasons for hunting, gathering, and planting. Consequently, we have applied a range of standard image processing algorithms (viz., edge detection, spatial filtering, spectral differencing, and contrast enhancement) as well as specialized techniques (e.g., matched filters) to the clarification of these drawings. Also, we report the results of computer enhancement studies pertaining to authenticity, faint details, sitter identity, and age of portraits by da Vinci, Rembrandt, Rotari, and Titian.

  17. Automated Coronal Loop Identification using Digital Image Processing Techniques

    NASA Astrophysics Data System (ADS)

    Lee, J. K.; Gary, G. A.; Newman, T. S.

    2003-05-01

    The results of a Master's thesis study of computer algorithms for automatic extraction and identification (i.e., collectively, "detection") of optically-thin, 3-dimensional, (solar) coronal-loop center "lines" from extreme ultraviolet and X-ray 2-dimensional images will be presented. The center lines, which can be considered to be splines, are proxies of magnetic field lines. Detecting the loops is challenging because there are no unique shapes, the loop edges are often indistinct, and because photon and detector noise heavily influence the images. Three techniques for detecting the projected magnetic field lines have been considered and will be described in the presentation. The three techniques used are (i) linear feature recognition of local patterns (related to the inertia-tensor concept), (ii) parametric space inferences via the Hough transform, and (iii) topological adaptive contours (snakes) that constrain curvature and continuity. Since coronal loop topology is dominated by the magnetic field structure, a first-order magnetic field approximation using multiple dipoles provides a priori information that has also been incorporated into the detection process. Synthesized images have been generated to benchmark the suitability of the three techniques, and the performance of the three techniques on both synthesized and solar images will be presented and numerically evaluated in the presentation. The process of automatic detection of coronal loops is important in the reconstruction of the coronal magnetic field where the derived magnetic field lines provide a boundary condition for magnetic models ( cf. , Gary (2001, Solar Phys., 203, 71) and Wiegelmann & Neukirch (2002, Solar Phys., 208, 233)). . This work was supported by NASA's Office of Space Science - Solar and Heliospheric Physics Supporting Research and Technology Program.

  18. Interpretation of Medical Imaging Data with a Mobile Application: A Mobile Digital Imaging Processing Environment

    PubMed Central

    Lin, Meng Kuan; Nicolini, Oliver; Waxenegger, Harald; Galloway, Graham J.; Ullmann, Jeremy F. P.; Janke, Andrew L.

    2013-01-01

    Digital Imaging Processing (DIP) requires data extraction and output from a visualization tool to be consistent. Data handling and transmission between the server and a user is a systematic process in service interpretation. The use of integrated medical services for management and viewing of imaging data in combination with a mobile visualization tool can be greatly facilitated by data analysis and interpretation. This paper presents an integrated mobile application and DIP service, called M-DIP. The objective of the system is to (1) automate the direct data tiling, conversion, pre-tiling of brain images from Medical Imaging NetCDF (MINC), Neuroimaging Informatics Technology Initiative (NIFTI) to RAW formats; (2) speed up querying of imaging measurement; and (3) display high-level of images with three dimensions in real world coordinates. In addition, M-DIP provides the ability to work on a mobile or tablet device without any software installation using web-based protocols. M-DIP implements three levels of architecture with a relational middle-layer database, a stand-alone DIP server, and a mobile application logic middle level realizing user interpretation for direct querying and communication. This imaging software has the ability to display biological imaging data at multiple zoom levels and to increase its quality to meet users’ expectations. Interpretation of bioimaging data is facilitated by an interface analogous to online mapping services using real world coordinate browsing. This allows mobile devices to display multiple datasets simultaneously from a remote site. M-DIP can be used as a measurement repository that can be accessed by any network environment, such as a portable mobile or tablet device. In addition, this system and combination with mobile applications are establishing a virtualization tool in the neuroinformatics field to speed interpretation services. PMID:23847587

  19. Interpretation of medical imaging data with a mobile application: a mobile digital imaging processing environment.

    PubMed

    Lin, Meng Kuan; Nicolini, Oliver; Waxenegger, Harald; Galloway, Graham J; Ullmann, Jeremy F P; Janke, Andrew L

    2013-01-01

    Digital Imaging Processing (DIP) requires data extraction and output from a visualization tool to be consistent. Data handling and transmission between the server and a user is a systematic process in service interpretation. The use of integrated medical services for management and viewing of imaging data in combination with a mobile visualization tool can be greatly facilitated by data analysis and interpretation. This paper presents an integrated mobile application and DIP service, called M-DIP. The objective of the system is to (1) automate the direct data tiling, conversion, pre-tiling of brain images from Medical Imaging NetCDF (MINC), Neuroimaging Informatics Technology Initiative (NIFTI) to RAW formats; (2) speed up querying of imaging measurement; and (3) display high-level of images with three dimensions in real world coordinates. In addition, M-DIP provides the ability to work on a mobile or tablet device without any software installation using web-based protocols. M-DIP implements three levels of architecture with a relational middle-layer database, a stand-alone DIP server, and a mobile application logic middle level realizing user interpretation for direct querying and communication. This imaging software has the ability to display biological imaging data at multiple zoom levels and to increase its quality to meet users' expectations. Interpretation of bioimaging data is facilitated by an interface analogous to online mapping services using real world coordinate browsing. This allows mobile devices to display multiple datasets simultaneously from a remote site. M-DIP can be used as a measurement repository that can be accessed by any network environment, such as a portable mobile or tablet device. In addition, this system and combination with mobile applications are establishing a virtualization tool in the neuroinformatics field to speed interpretation services.

  20. Digital mapping of side-scan sonar data with the Woods Hole Image Processing System software

    USGS Publications Warehouse

    Paskevich, Valerie F.

    1992-01-01

    Since 1985, the Branch of Atlantic Marine Geology has been involved in collecting, processing and digitally mosaicking high and low resolution sidescan sonar data. In the past, processing and digital mosaicking has been accomplished with a dedicated, shore-based computer system. Recent development of a UNIX-based image-processing software system includes a series of task specific programs for pre-processing sidescan sonar data. To extend the capabilities of the UNIX-based programs, development of digital mapping techniques have been developed. This report describes the initial development of an automated digital mapping procedure. Included is a description of the programs and steps required to complete the digital mosaicking on a UNIXbased computer system, and a comparison of techniques that the user may wish to select.

  1. Image processing for a tactile/vision substitution system using digital CNN.

    PubMed

    Lin, Chien-Nan; Yu, Sung-Nien; Hu, Jin-Cheng

    2006-01-01

    In view of the parallel processing and easy implementation properties of CNN, we propose to use digital CNN as the image processor of a tactile/vision substitution system (TVSS). The digital CNN processor is used to execute the wavelet down-sampling filtering and the half-toning operations, aiming to extract important features from the images. A template combination method is used to embed the two image processing functions into a single CNN processor. The digital CNN processor is implemented on an intellectual property (IP) and is implemented on a XILINX VIRTEX II 2000 FPGA board. Experiments are designated to test the capability of the CNN processor in the recognition of characters and human subjects in different environments. The experiments demonstrates impressive results, which proves the proposed digital CNN processor a powerful component in the design of efficient tactile/vision substitution systems for the visually impaired people.

  2. Wavelet image processing applied to optical and digital holography: past achievements and future challenges

    NASA Astrophysics Data System (ADS)

    Jones, Katharine J.

    2005-08-01

    The link between wavelets and optics goes back to the work of Dennis Gabor who both invented holography and developed Gabor decompositions. Holography involves 3-D images. Gabor decompositions involves 1-D signals. Gabor decompositions are the predecessors of wavelets. Wavelet image processing of holography, both optical holography and digital holography, will be examined with respect to past achievements and future challenges.

  3. Digital image database processing to simulate image formation in ideal lighting conditions of the human eye

    NASA Astrophysics Data System (ADS)

    Castañeda-Santos, Jessica; Santiago-Alvarado, Agustin; Cruz-Félix, Angel S.; Hernández-Méndez, Arturo

    2015-09-01

    The pupil size of the human eye has a large effect in the image quality due to inherent aberrations. Several studies have been performed to calculate its size relative to the luminance as well as considering other factors, i.e., age, size of the adapting field and mono and binocular vision. Moreover, ideal lighting conditions are known, but software suited to our specific requirements, low cost and low computational consumption, in order to simulate radiation adaptation and image formation in the retina with ideal lighting conditions has not yet been developed. In this work, a database is created consisting of 70 photographs corresponding to the same scene with a fixed target at different times of the day. By using this database, characteristics of the photographs are obtained by measuring the luminance average initial threshold value of each photograph by means of an image histogram. Also, we present the implementation of a digital filter for both, image processing on the threshold values of our database and generating output images with the threshold values reported for the human eye in ideal cases. Some potential applications for this kind of filters may be used in artificial vision systems.

  4. Automated microstructural analysis of titanium alloys using digital image processing

    NASA Astrophysics Data System (ADS)

    Campbell, A.; Murray, P.; Yakushina, E.; Marshall, S.; Ion, W.

    2017-02-01

    Titanium is a material that exhibits many desirable properties including a very high strength to weight ratio and corrosive resistance. However, the specific properties of any components depend upon the microstructure of the material, which varies by the manufacturing process. This means it is often necessary to analyse the microstructure when designing new processes or performing quality assurance on manufactured parts. For Ti6Al4V, grain size analysis is typically performed manually by expert material scientists as the complicated microstructure of the material means that, to the authors knowledge, no existing software reliably identifies the grain boundaries. This manual process is time consuming and offers low repeatability due to human error and subjectivity. In this paper, we propose a new, automated method to segment microstructural images of a Ti6Al4V alloy into its constituent grains and produce measurements. The results of applying this technique are evaluated by comparing the measurements obtained by different analysis methods. By using measurements from a complete manual segmentation as a benchmark we explore the reliability of the current manual estimations of grain size and contrast this with improvements offered by our approach.

  5. All-digital precision processing of ERTS images

    NASA Technical Reports Server (NTRS)

    Bernstein, R. (Principal Investigator)

    1975-01-01

    The author has identified the following significant results. Digital techniques have been developed and used to apply precision-grade radiometric and geometric corrections to ERTS MSS and RBV scenes. Geometric accuracies sufficient for mapping at 1:250,000 scale have been demonstrated. Radiometric quality has been superior to ERTS NDPF precision products. A configuration analysis has shown that feasible, cost-effective all-digital systems for correcting ERTS data are easily obtainable. This report contains a summary of all results obtained during this study and includes: (1) radiometric and geometric correction techniques, (2) reseau detection, (3) GCP location, (4) resampling, (5) alternative configuration evaluations, and (6) error analysis.

  6. Digital Processing and Segmentation of Breast Microcalcifications Images Obtained by a Si Microstrips Detector: Preliminary Results

    SciTech Connect

    Diaz, Claudia C.; Angulo, Abril A.

    2007-02-09

    We present the preliminary results of digital processing and segmentation of breast microcalcifications images. They were obtained using a Bede X ray tube with Cu anode, which was fixed at 20 kV and 1 mA. Different biopsies were scanned using a 128 Si microstrips detector. Total scanning resulted in a data matrix, which corresponded with the image of each biopsy. We manipulated the contrast of the images using histograms and filters in the frequency domain in Matlab. Then we intended to investigate about different contour models for the segmentation of microcalcifications boundaries, which were based on the contrast and shape of the image. These algorithms could be applied to mammographic images, which may be obtained by digital mammography or digitizing conventional mammograms.

  7. Digital Imaging.

    ERIC Educational Resources Information Center

    Howell, Les

    1996-01-01

    Defines a digital photograph as a numerical record of light electronically measured and recorded by a computer's scanner. States that most personal computers cannot do digital photography successfully and that digital pictures can be hard to manage and present a storage problem. Finds that, once the school has the hardware/software, picture…

  8. Digital Imaging.

    ERIC Educational Resources Information Center

    Howell, Les

    1996-01-01

    Defines a digital photograph as a numerical record of light electronically measured and recorded by a computer's scanner. States that most personal computers cannot do digital photography successfully and that digital pictures can be hard to manage and present a storage problem. Finds that, once the school has the hardware/software, picture…

  9. Considerations in developing geographic informations systems based on low-cost digital image processing

    NASA Technical Reports Server (NTRS)

    Henderson, F. M.; Dobson, M. W.

    1981-01-01

    The potential of digital image processing systems costing $20,000 or less for geographic information systems is assessed with the emphasis on the volume of data to be handled, the commercial hardware systems available, and the basic software for: (1) data entry, conversion and digitization; (2) georeferencing and geometric correction; (3) data structuring; (4) editing and updating; (5) analysis and retrieval; (6) output drivers; and (7) data management. Costs must also be considered as tangible and intangible factors.

  10. Considerations in developing geographic informations systems based on low-cost digital image processing

    NASA Technical Reports Server (NTRS)

    Henderson, F. M.; Dobson, M. W.

    1981-01-01

    The potential of digital image processing systems costing $20,000 or less for geographic information systems is assessed with the emphasis on the volume of data to be handled, the commercial hardware systems available, and the basic software for: (1) data entry, conversion and digitization; (2) georeferencing and geometric correction; (3) data structuring; (4) editing and updating; (5) analysis and retrieval; (6) output drivers; and (7) data management. Costs must also be considered as tangible and intangible factors.

  11. Applications of digital image processing IX: SPIE volume 697

    SciTech Connect

    Teacher, A.G.

    1986-01-01

    This book contains papers arranged into six sessions. The session titles are: Image compression; Instrumentation; Theoretical concepts; Algorithms; Registration and modeling; and Restoration and enhancement.

  12. Digital TV image enhancement system

    NASA Technical Reports Server (NTRS)

    Biernson, G. A.

    1973-01-01

    Efficient, digital image-enhancement process has been developed for high-resolution slow-scan TV images. Scan converter is no longer subject to registration errors, which become more serious as resolution increases. To implement feedback image enhancement system, digital processing is used; otherwise there is excessive loss of image information, particularly in video delay lines.

  13. Digital Image Analysis of Cereals

    USDA-ARS?s Scientific Manuscript database

    Image analysis is the extraction of meaningful information from images, mainly digital images by means of digital processing techniques. The field was established in the 1950s and coincides with the advent of computer technology, as image analysis is profoundly reliant on computer processing. As t...

  14. Computational analysis of Pelton bucket tip erosion using digital image processing

    NASA Astrophysics Data System (ADS)

    Shrestha, Bim Prasad; Gautam, Bijaya; Bajracharya, Tri Ratna

    2008-03-01

    Erosion of hydro turbine components through sand laden river is one of the biggest problems in Himalayas. Even with sediment trapping systems, complete removal of fine sediment from water is impossible and uneconomical; hence most of the turbine components in Himalayan Rivers are exposed to sand laden water and subject to erode. Pelton bucket which are being wildly used in different hydropower generation plant undergoes erosion on the continuous presence of sand particles in water. The subsequent erosion causes increase in splitter thickness, which is supposed to be theoretically zero. This increase in splitter thickness gives rise to back hitting of water followed by decrease in turbine efficiency. This paper describes the process of measurement of sharp edges like bucket tip using digital image processing. Image of each bucket is captured and allowed to run for 72 hours; sand concentration in water hitting the bucket is closely controlled and monitored. Later, the image of the test bucket is taken in the same condition. The process is repeated for 10 times. In this paper digital image processing which encompasses processes that performs image enhancement in both spatial and frequency domain. In addition, the processes that extract attributes from images, up to and including the measurement of splitter's tip. Processing of image has been done in MATLAB 6.5 platform. The result shows that quantitative measurement of edge erosion of sharp edges could accurately be detected and the erosion profile could be generated using image processing technique.

  15. Interactive Digital Image Processing for Terrain Data Extraction, Phase 4.

    DTIC Science & Technology

    1983-11-01

    the images appear to be displaced radial1l toward the isocenter on the upper side of the photograph and radially outward or away from the isocenter ...on the lower side. Along the isometric parallel (line through the isocenter perpendicular to the direction of tilt) there is no displacement relative...the principal point P (geometric center. This is equal to the Focal lengtr of the camera. t = Tilt angle i = Isocenter n = Nadir Di = Distance of image

  16. Digital Imaging in Cytopathology

    PubMed Central

    Khalbuss, Walid E.; Pantanowitz, Liron; Parwani, Anil V.

    2011-01-01

    Rapid advances are occurring in the field of cytopathology, particularly in the field of digital imaging. Today, digital images are used in a variety of settings including education (E-education), as a substitute to multiheaded sessions, multisite conferences, publications, cytopathology web pages, cytology proficiency testing, telecytology, consultation through telecytology, and automated screening of Pap test slides. The accessibility provided by digital imaging in cytopathology can improve the quality and efficiency of cytopathology services, primarily by getting the expert cytopathologist to remotely look at the slide. This improved accessibility saves time and alleviates the need to ship slides, wait for glass slides, or transport pathologists. Whole slide imaging (WSI) is a digital imaging modality that uses computerized technology to scan and convert pathology and cytology glass slides into digital images (digital slides) that can be viewed remotely on a workstation using viewing software. In spite of the many advances, challenges remain such as the expensive initial set-up costs, workflow interruption, length of time to scan whole slides, large storage size for WSI, bandwidth restrictions, undefined legal implications, professional reluctance, and lack of standardization in the imaging process. PMID:21785680

  17. Electron cryomicroscopy and digital image processing of lipoprotein(a).

    PubMed

    Sines, J; Rothnagel, R; van Heel, M; Gaubatz, J W; Morrisett, J D; Chiu, W

    1994-01-01

    Electron cryomicroscopy was used to study the structure of human lipoprotein(a) (Lp(a)), a plasma lipoprotein implicated in cardiovascular disease. An individual Lp(a) particle consists of a neutral lipid core within a shell of phospholipid, cholesterol and glycoprotein. In principle, electron cryomicroscopy images of single particles should contain structural detail attributable to the density differences among these components and the surrounding buffer. We observed such structural detail in images of frozen, hydrated Lp(a) particles. Lp(a) particles appeared to be roughly spherical in shape with an average diameter of 210 A. As is generally true for unstained samples in vitreous ice, imaged with a low electron dose, these images have low contrast with low signal-to-noise ratios. To increase the signal-to-noise ratio, we averaged classes of similar particles. We began with a set of 5813 randomly oriented Lp(a) particles and generated classes using a linear multivariate statistical method, followed by hierarchical ascendant classification. Our initial classification, based on only the first eight eigenvectors, separated particles on the basis of gross size and shape. After a rough reference-free alignment step, a second classification used the finer details in the images. This approach yielded class averages with structural detail only faintly visible in the raw, single images.

  18. Applications of digital image processing techniques to problems of data registration and correlation

    NASA Technical Reports Server (NTRS)

    Green, W. B.

    1978-01-01

    An overview is presented of the evolution of the computer configuration at JPL's Image Processing Laboratory (IPL). The development of techniques for the geometric transformation of digital imagery is discussed and consideration is given to automated and semiautomated image registration, and the registration of imaging and nonimaging data. The increasing complexity of image processing tasks at IPL is illustrated with examples of various applications from the planetary program and earth resources activities. It is noted that the registration of existing geocoded data bases with Landsat imagery will continue to be important if the Landsat data is to be of genuine use to the user community.

  19. Current status on the application of image processing of digital intraoral radiographs amongst general dental practitioners.

    PubMed

    Tohidast, Parisa; Shi, Xie-Qi

    2016-01-01

    The objectives of this study were to present the subjective knowledge level and the use of image processing on digital intraoral radiographs amongst general dental practitioners at Distriktståndvrden AB, Stockholm. A questionnaire, consisting of12 questions, was sent to 12 dental prac- tices in Stockholm. Additionally, 2000 radiographs were randomly selected from these clinics for evaluation of applied image processing and its effect on image quality. Descriptive and analytical statistical methods were applied to present the current status of the use of image proces- sing alternatives for the dentists' daily clinical work. 50 out of 53 dentists participated in the survey.The survey showed that most of dentists in.this study had received education on image processing at some stage of their career. No correlations were found between application of image processing on one side and educa- tion received with regards to image processing, previous working experience, age and gender on the other. Image processing in terms of adjusting brightness and contrast was frequently used. Overall, in this study 24.5% of the 200 images were actually image processed in practice, in which 90% of the images were improved or maintained in image quality. According to our survey, image processing is experienced to be frequently used by the dentists at Distriktstandvåden AB for diagnosing anatomical and pathological changes using intraoral radiographs. 24.5% of the 200 images were actually image processed in terms of adjusting brightness and/or contrast. In the present study we did not found that the dentists' age, gender, previous working experience and education in image processing influence their viewpoint towards the application of image processing.

  20. Interactive Digital Image Processing for Terrain Data Extraction.

    DTIC Science & Technology

    1984-09-01

    in Figure 3.3.1.2. 3.3.2 Image Rectification An aerial photograph is almost always tilted by a small amount since there is no mechanism available to...radial from the isocenter . It varies with the square of the radial distance and with the cosine of the angle that a line through the image and the... Isocenter makes with the direction of tilt. The displacement is positive on one side of the photograph and negative on the other side. There is a line on

  1. Real-time digital signal processing for live electro-optic imaging.

    PubMed

    Sasagawa, Kiyotaka; Kanno, Atsushi; Tsuchiya, Masahiro

    2009-08-31

    We present an imaging system that enables real-time magnitude and phase detection of modulated signals and its application to a Live Electro-optic Imaging (LEI) system, which realizes instantaneous visualization of RF electric fields. The real-time acquisition of magnitude and phase images of a modulated optical signal at 5 kHz is demonstrated by imaging with a Si-based high-speed CMOS image sensor and real-time signal processing with a digital signal processor. In the LEI system, RF electric fields are probed with light via an electro-optic crystal plate and downconverted to an intermediate frequency by parallel optical heterodyning, which can be detected with the image sensor. The artifacts caused by the optics and the image sensor characteristics are corrected by image processing. As examples, we demonstrate real-time visualization of electric fields from RF circuits.

  2. A Method for Identifying Contours in Processing Digital Images from Computer Tomograph

    NASA Astrophysics Data System (ADS)

    Roşu, Şerban; Pater, Flavius; Costea, Dan; Munteanu, Mihnea; Roşu, Doina; Fratila, Mihaela

    2011-09-01

    The first step in digital processing of two-dimensional computed tomography images is to identify the contour of component elements. This paper deals with the collective work of specialists in medicine and applied mathematics in computer science on elaborating new algorithms and methods in medical 2D and 3D imagery.

  3. Digital image processing applications in the ignition and combustion of char/coal particles

    SciTech Connect

    Annamalai, K.; Kharbat, E.; Goplakrishnan, C.

    1992-12-01

    Digital image processing, is employed in this remarch study in order to visually investigate the ignition and combustion characteristics of isolated char/coal particles as well as the effect of interactivecombustion in two-particle char/coal arrays. Preliminary experiments are conducted on miniature isolated candles as well as two-candle arrays.

  4. The impact of digital image processing artefacts mimicking pathological features associated with restorations.

    PubMed

    Brettle, D; Carmichael, F

    2011-08-26

    Image processing of digital X-ray images is known to have the potential to produce artefacts that may mimic pathology. A study was conducted at a UK dental radiology conference to demonstrate this effect in dentistry. Sixteen digital X-rays of single teeth containing restorations were randomly presented in both unprocessed and processed formats to an auditorium of 42 participants. Participants interactively scored each image on a scale from 1-5 where 1 was definitely no pathology and 5 was definitely pathology. The display conditions were confirmed for each participant using a validated threshold contrast test. The results show that 52% (81/157) of responses at level 1 for the unprocessed images changed to levels 4 or 5 after image processing. This study illustrates the potential for image processing artefacts to mimic pathology particularly at high contrast boundaries and introduces the risk of unnecessary interventions. In order to minimise this risk, it is recommended that for digital radiographs containing pathology relating to high contrast boundaries, non-related high contrast features such as unrelated restorations or tooth/bone margins are also considered to exclude the possibility of artefact. If there is doubt, reference should be made to the unprocessed data.

  5. Opportunities in IT Support of Workflow & Information Flow in the Emergency Department Digital Imaging Process.

    PubMed

    Fairbanks, R J; Guarrera, T K; Bisantz, A B; Venturino, M; Westesson, P L

    2010-09-01

    The goal of this study is to examine workflow and information flow in the emergency department (ED) digital imaging process to identify features of an optimized system. Radiological imaging (x-rays, CT scans, etc) is unique in the ED setting, as the need for fast turn-around time and interactive communication between radiologists and emergency physicians is different than that of most other healthcare settings. The information technology systems which are used by both radiologists and emergency physicians to support these processes have been designed with a focus on the routine workflow of radiologists. We report the results of 14 hours of naturalistic observations of the use of digital imaging systems by a total of 22 ED and radiology staff. A hierarchical task analysis and an information process diagram are presented, and disparate theories that groups in the system have about other groups were discovered, particularly in the communication of clinical information.

  6. Optimizing Digital Mammographic Image Quality for Full-Field Digital Detectors: Artifacts Encountered during the QC Process.

    PubMed

    Jayadevan, Rashmi; Armada, M Julie; Shaheen, Rola; Mulcahy, Constance; Slanetz, Priscilla J

    2015-01-01

    Early detection of breast cancer through routine mammographic screening has been shown to reduce mortality from breast cancer by up to 30% in multiple studies. However, this reduction of mortality is possible only with careful attention to image quality by the medical physicist, radiologic technologist, and interpreting radiologist. The accepted quality control (QC) processes for analog mammography are well established. However, now that use of digital units is widespread in both the United States and internationally, information regarding the necessary steps and the inherent challenges that might be encountered at each step needs to be elucidated. In this review, the essential steps of the QC process for digital mammography are reviewed, with special attention to the possible problems that can occur during the QC process, many of which can lead to image artifacts. For each of the daily, weekly, monthly, and semiannual QC tests, we review the steps and expected performance and provide examples of some of the common artifacts that may be encountered. Understanding the components of the QC process and recognizing problems that may result in a suboptimal image is critical to ensure optimal image quality in an effort to maximize early detection of breast cancer. (©)RSNA, 2015.

  7. Principles of digital imaging.

    PubMed

    van der Stelt, P F

    2000-04-01

    Electronic sensors in diagnostic radiology are gradually replacing radiographic film. The advantages of this new technology include a lower radiation dose to the patient, an almost instantaneous availability of images without the need for chemical film processing, and the possibility of image enhancement and computer-aided feature extraction. Digital radiography is a promising technology, opening the door to new diagnostic procedures not available with traditional film-based imaging.

  8. Application of digital image processing techniques to faint solar flare phenomena

    NASA Technical Reports Server (NTRS)

    Glackin, D. L.; Martin, S. F.

    1980-01-01

    Digital image processing of eight solar flare events was performed using the Video Information Communication and Retrieval language in order to study moving emission fronts, flare halos, and Moreton waves. The techniques used include contrast enhancement, isointensity contouring, the differencing of images, spatial filtering, and geometrical registration. The spatial extent and temporal behavior of the faint phenomena is examined along with the relation of the three types of phenomena to one another. The image processing techniques make possible the detailed study of the history of the phenomena and provide clues to their physical nature.

  9. [Research and realization of signal processing algorithms based on FPGA in digital ophthalmic ultrasonography imaging].

    PubMed

    Fang, Simin; Zhou, Sheng; Wang, Xiaochun; Ye, Qingsheng; Tian, Ling; Ji, Jianjun; Wang, Yanqun

    2015-01-01

    To design and improve signal processing algorithms of ophthalmic ultrasonography based on FPGA. Achieved three signal processing modules: full parallel distributed dynamic filter, digital quadrature demodulation, logarithmic compression, using Verilog HDL hardware language in Quartus II. Compared to the original system, the hardware cost is reduced, the whole image shows clearer and more information of the deep eyeball contained in the image, the depth of detection increases from 5 cm to 6 cm. The new algorithms meet the design requirements and achieve the system's optimization that they can effectively improve the image quality of existing equipment.

  10. Application of digital image processing techniques to faint solar flare phenomena

    NASA Technical Reports Server (NTRS)

    Glackin, D. L.; Martin, S. F.

    1980-01-01

    Digital image processing of eight solar flare events was performed using the Video Information Communication and Retrieval language in order to study moving emission fronts, flare halos, and Moreton waves. The techniques used include contrast enhancement, isointensity contouring, the differencing of images, spatial filtering, and geometrical registration. The spatial extent and temporal behavior of the faint phenomena is examined along with the relation of the three types of phenomena to one another. The image processing techniques make possible the detailed study of the history of the phenomena and provide clues to their physical nature.

  11. Experimental study of digital image processing techniques for LANDSAT data

    NASA Technical Reports Server (NTRS)

    Rifman, S. S. (Principal Investigator); Allendoerfer, W. B.; Caron, R. H.; Pemberton, L. J.; Mckinnon, D. M.; Polanski, G.; Simon, K. W.

    1976-01-01

    The author has identified the following significant results. Results are reported for: (1) subscene registration, (2) full scene rectification and registration, (3) resampling techniques, (4) and ground control point (GCP) extraction. Subscenes (354 pixels x 234 lines) were registered to approximately 1/4 pixel accuracy and evaluated by change detection imagery for three cases: (1) bulk data registration, (2) precision correction of a reference subscene using GCP data, and (3) independently precision processed subscenes. Full scene rectification and registration results were evaluated by using a correlation technique to measure registration errors of 0.3 pixel rms thoughout the full scene. Resampling evaluations of nearest neighbor and TRW cubic convolution processed data included change detection imagery and feature classification. Resampled data were also evaluated for an MSS scene containing specular solar reflections.

  12. Characterization of Periodically Poled Nonlinear Materials Using Digital Image Processing

    DTIC Science & Technology

    2008-04-01

    Interactions Due to the nonlinear nature of the response, a nonlinear polarization at new frequencies is generated which can radiate at frequencies not...present in the incident radiation field. This coupling allows energy to be transferred between different wavelengths and forms the basis of the...physical mechanism behind these processes. An isolated atom would radiate in the typical dipole radiation pattern, but in a material, a large number of

  13. Digital camera workflow for high dynamic range images using a model of retinal processing

    NASA Astrophysics Data System (ADS)

    Tamburrino, Daniel; Alleysson, David; Meylan, Laurence; Süsstrunk, Sabine

    2008-02-01

    We propose a complete digital camera workflow to capture and render high dynamic range (HDR) static scenes, from RAW sensor data to an output-referred encoded image. In traditional digital camera processing, demosaicing is one of the first operations done after scene analysis. It is followed by rendering operations, such as color correction and tone mapping. In our workflow, which is based on a model of retinal processing, most of the rendering steps are performed before demosaicing. This reduces the complexity of the computation, as only one third of the pixels are processed. This is especially important as our tone mapping operator applies local and global tone corrections, which is usually needed to well render high dynamic scenes. Our algorithms efficiently process HDR images with different keys and different content.

  14. Image digitalization and processing of contact lens fitting to astigmatic eyes

    NASA Astrophysics Data System (ADS)

    Costa, Manuel F. M.

    1998-01-01

    The use of standard CCD cameras and image digitalization and processing on medical diagnosis are more and more frequent. The correction of human eye's refraction problems by the use of contact lenses is generalized. In spite its advantages in terms of users comfort, special care must be taken on its prescription and adaptation. Astigmatic eyes often place the highest problems. A careful assessment of the quality of the lens to cornea adaptation must to be performed. The basic and more traditional way to check the contact lens' fitting is to perform a fluorescein test. We intend to make the process more convenient for both patient and optometrist. The fluorescence images are acquired by a CCD camera and then digitized and processed in order to produce a semi- automated process.

  15. Automatic Rice Crop Height Measurement Using a Field Server and Digital Image Processing

    PubMed Central

    Sritarapipat, Tanakorn; Rakwatin, Preesan; Kasetkasem, Teerasit

    2014-01-01

    Rice crop height is an important agronomic trait linked to plant type and yield potential. This research developed an automatic image processing technique to detect rice crop height based on images taken by a digital camera attached to a field server. The camera acquires rice paddy images daily at a consistent time of day. The images include the rice plants and a marker bar used to provide a height reference. The rice crop height can be indirectly measured from the images by measuring the height of the marker bar compared to the height of the initial marker bar. Four digital image processing steps are employed to automatically measure the rice crop height: band selection, filtering, thresholding, and height measurement. Band selection is used to remove redundant features. Filtering extracts significant features of the marker bar. The thresholding method is applied to separate objects and boundaries of the marker bar versus other areas. The marker bar is detected and compared with the initial marker bar to measure the rice crop height. Our experiment used a field server with a digital camera to continuously monitor a rice field located in Suphanburi Province, Thailand. The experimental results show that the proposed method measures rice crop height effectively, with no human intervention required. PMID:24451465

  16. Automatic rice crop height measurement using a field server and digital image processing.

    PubMed

    Sritarapipat, Tanakorn; Rakwatin, Preesan; Kasetkasem, Teerasit

    2014-01-07

    Rice crop height is an important agronomic trait linked to plant type and yield potential. This research developed an automatic image processing technique to detect rice crop height based on images taken by a digital camera attached to a field server. The camera acquires rice paddy images daily at a consistent time of day. The images include the rice plants and a marker bar used to provide a height reference. The rice crop height can be indirectly measured from the images by measuring the height of the marker bar compared to the height of the initial marker bar. Four digital image processing steps are employed to automatically measure the rice crop height: band selection, filtering, thresholding, and height measurement. Band selection is used to remove redundant features. Filtering extracts significant features of the marker bar. The thresholding method is applied to separate objects and boundaries of the marker bar versus other areas. The marker bar is detected and compared with the initial marker bar to measure the rice crop height. Our experiment used a field server with a digital camera to continuously monitor a rice field located in Suphanburi Province, Thailand. The experimental results show that the proposed method measures rice crop height effectively, with no human intervention required.

  17. [Optimization of digital chest radiography image post-processing in diagnosis of pneumoconiosis].

    PubMed

    Sheng, Bing-yong; Mao, Ling; Zhou, Shao-wei; Shi, Jin

    2013-11-01

    To establish the optimal image post-processing parameters for digital chest radiography as preliminary research for introducing digital radiography (DR) to pneumoconiosis diagnosis in China. A total of 204 pneumoconiosis patients and 31 dust-exposed workers were enrolled as the subjects in this research. Film-screen radiography (FSR) and DR images were taken for all subjects. DR films were printed after raw images were processed and parameters were altered using DR workstation (GE Healthcare, U.S.A.). Image gradations, lung textures, and the imaging of thoracic vertebra were evaluated by pneumoconiosis experts, and the optimal post-processing parameters were selected. Optical density was measured for both DR films and FSR films. For the DR machine used in this research, the contrast adjustment (CA) and brightness adjustment (BA) were the main parameters that determine the brightness and gray levels of images. The optimal ranges for CA and BA were 115%∼120% and 160%∼165%, respectively. The quality of DR chest films would be optimized when tissue contrast was adjusted to a maximum of 0.15, edge to a minimum of 1, and both noise reduction and tissue equalization to0.The failure rate of chest DR (0.4%) was significantly lower than that of chest FSR (17%) (P < 0.05). After appropriate image post-processing on DR machine purchased from GE Healthcare, the DR chest films can meet all requirements for the quality of chest X-ray films in the Chinese diagnostic criteria for pneumoconiosis.

  18. Quantitative fractography by digital image processing: NIH Image macro tools for stereo pair analysis and 3-D reconstruction.

    PubMed

    Hein, L R

    2001-10-01

    A set of NIH Image macro programs was developed to make qualitative and quantitative analyses from digital stereo pictures produced by scanning electron microscopes. These tools were designed for image alignment, anaglyph representation, animation, reconstruction of true elevation surfaces, reconstruction of elevation profiles, true-scale elevation mapping and, for the quantitative approach, surface area and roughness calculations. Limitations on time processing, scanning techniques and programming concepts are also discussed.

  19. Mammographic density assessed on paired raw and processed digital images and on paired screen-film and digital images across three mammography systems.

    PubMed

    Burton, Anya; Byrnes, Graham; Stone, Jennifer; Tamimi, Rulla M; Heine, John; Vachon, Celine; Ozmen, Vahit; Pereira, Ana; Garmendia, Maria Luisa; Scott, Christopher; Hipwell, John H; Dickens, Caroline; Schüz, Joachim; Aribal, Mustafa Erkin; Bertrand, Kimberly; Kwong, Ava; Giles, Graham G; Hopper, John; Pérez Gómez, Beatriz; Pollán, Marina; Teo, Soo-Hwang; Mariapun, Shivaani; Taib, Nur Aishah Mohd; Lajous, Martín; Lopez-Riduara, Ruy; Rice, Megan; Romieu, Isabelle; Flugelman, Anath Arzee; Ursin, Giske; Qureshi, Samera; Ma, Huiyan; Lee, Eunjung; Sirous, Reza; Sirous, Mehri; Lee, Jong Won; Kim, Jisun; Salem, Dorria; Kamal, Rasha; Hartman, Mikael; Miao, Hui; Chia, Kee-Seng; Nagata, Chisato; Vinayak, Sudhir; Ndumia, Rose; van Gils, Carla H; Wanders, Johanna O P; Peplonska, Beata; Bukowska, Agnieszka; Allen, Steve; Vinnicombe, Sarah; Moss, Sue; Chiarelli, Anna M; Linton, Linda; Maskarinec, Gertraud; Yaffe, Martin J; Boyd, Norman F; Dos-Santos-Silva, Isabel; McCormack, Valerie A

    2016-12-19

    Inter-women and intra-women comparisons of mammographic density (MD) are needed in research, clinical and screening applications; however, MD measurements are influenced by mammography modality (screen film/digital) and digital image format (raw/processed). We aimed to examine differences in MD assessed on these image types. We obtained 1294 pairs of images saved in both raw and processed formats from Hologic and General Electric (GE) direct digital systems and a Fuji computed radiography (CR) system, and 128 screen-film and processed CR-digital pairs from consecutive screening rounds. Four readers performed Cumulus-based MD measurements (n = 3441), with each image pair read by the same reader. Multi-level models of square-root percent MD were fitted, with a random intercept for woman, to estimate processed-raw MD differences. Breast area did not differ in processed images compared with that in raw images, but the percent MD was higher, due to a larger dense area (median 28.5 and 25.4 cm(2) respectively, mean √dense area difference 0.44 cm (95% CI: 0.36, 0.52)). This difference in √dense area was significant for direct digital systems (Hologic 0.50 cm (95% CI: 0.39, 0.61), GE 0.56 cm (95% CI: 0.42, 0.69)) but not for Fuji CR (0.06 cm (95% CI: -0.10, 0.23)). Additionally, within each system, reader-specific differences varied in magnitude and direction (p < 0.001). Conversion equations revealed differences converged to zero with increasing dense area. MD differences between screen-film and processed digital on the subsequent screening round were consistent with expected time-related MD declines. MD was slightly higher when measured on processed than on raw direct digital mammograms. Comparisons of MD on these image formats should ideally control for this non-constant and reader-specific difference.

  20. Digital image capture, processing, and recording system upgrade for the APS-94F SLAR

    NASA Astrophysics Data System (ADS)

    Ferraris, Guillermo L.

    2000-11-01

    The Argentine Army has been operating the APS-94F SLAR systems, on board the venerable OV-1D MOHAWK aircraft, since 1996. These systems were received from the U.S. Government through the FMS program. One major handicap of the system is due to the now obsolete imagery recording subsystem, which includes complex optical, thermal and electro-mechanical obsolete processes and components, that account for most of the degradations and distortions in the images obtained (not to mention the fact that images are recorded on a 9.5-inch silver halide film media, which has to be kept at -17 degree(s)C and has to be brought to thermal equilibrium with the environment eight hours before the mission). An integral digital capture, processing and recording subsystem was developed at CITEFA (Instituto de Investigaciones Cientificas y Tecnicas de las Fuerzas Armadas) to replace the old analog RO-495/U recorder, as an upgrade to this very robust and proven imaging radar system The subsystem developed includes three custom designed ISA boards: (1) Radar video and aircraft attitude signal conditioning board, (2) Microprocessor controlled two- channel high speed digitizing board and (3) Integrated 12- channel GPS OEM board. The operator's software interface is a PC based GUI C++ application, including radar imagery forming and processing algorithms, slant range to ground range conversion, digitally controlled image gain, bias and contrast adjustments, image registration (GPS), image file disk recording and retrieval functions, real time mensuration and MTI/FTI (moving target indication/fixed target indication) image correlation. The system also provides for the added capability to send compressed still radar images in NRT (near real time) to a ground receiving station through a secure data link. Due to serious space limitations inside the OV-1D two-seat cockpit, a military grade ruggedized laptop computer and docking station hardware implementation was selected.

  1. TRIIG - Time-lapse reproduction of images through interactive graphics. [digital processing of quality hard copy

    NASA Technical Reports Server (NTRS)

    Buckner, J. D.; Council, H. W.; Edwards, T. R.

    1974-01-01

    Description of the hardware and software implementing the system of time-lapse reproduction of images through interactive graphics (TRIIG). The system produces a quality hard copy of processed images in a fast and inexpensive manner. This capability allows for optimal development of processing software through the rapid viewing of many image frames in an interactive mode. Three critical optical devices are used to reproduce an image: an Optronics photo reader/writer, the Adage Graphics Terminal, and Polaroid Type 57 high speed film. Typical sources of digitized images are observation satellites, such as ERTS or Mariner, computer coupled electron microscopes for high-magnification studies, or computer coupled X-ray devices for medical research.

  2. Digital image processing applied to analysis of geophysical and geochemical data for southern Missouri

    NASA Technical Reports Server (NTRS)

    Guinness, E. A.; Arvidson, R. E.; Leff, C. E.; Edwards, M. H.; Bindschadler, D. L.

    1983-01-01

    Digital image-processing techniques have been used to analyze a variety of geophysical and geochemical map data covering southern Missouri, a region with important basement and strata-bound mineral deposits. Gravity and magnetic anomaly patterns, which have been reformatted to image displays, indicate a deep crustal structure cutting northwest-southeast through southern Missouri. In addition, geologic map data, topography, and Landsat multispectral scanner images have been used as base maps for the digital overlay of aerial gamma-ray and stream sediment chemical data for the 1 x 2-deg Rolla quadrangle. Results indicate enrichment of a variety of elements within the clay-rich alluvium covering many of the interfluvial plains, as well as a complicated pattern of enrichment for the sedimentary units close to the Precambrian rhyolites and granites of the St. Francois Mountains.

  3. PREFACE: I International Scientific School Methods of Digital Image Processing in Optics and Photonics

    NASA Astrophysics Data System (ADS)

    Gurov, I. P.; Kozlov, S. A.

    2014-09-01

    The first international scientific school "Methods of Digital Image Processing in Optics and Photonics" was held with a view to develop cooperation between world-class experts, young scientists, students and post-graduate students, and to exchange information on the current status and directions of research in the field of digital image processing in optics and photonics. The International Scientific School was managed by: Saint Petersburg National Research University of Information Technologies, Mechanics and Optics (ITMO University) - Saint Petersburg (Russia) Chernyshevsky Saratov State University - Saratov (Russia) National research nuclear University "MEPHI" (NRNU MEPhI) - Moscow (Russia) The school was held with the participation of the local chapters of Optical Society of America (OSA), the Society of Photo-Optical Instrumentation Engineers (SPIE) and IEEE Photonics Society. Further details, including topics, committees and conference photos are available in the PDF

  4. A new approach to pre-processing digital image for wavelet-based watermark

    NASA Astrophysics Data System (ADS)

    Agreste, Santa; Andaloro, Guido

    2008-11-01

    The growth of the Internet has increased the phenomenon of digital piracy, in multimedia objects, like software, image, video, audio and text. Therefore it is strategic to individualize and to develop methods and numerical algorithms, which are stable and have low computational cost, that will allow us to find a solution to these problems. We describe a digital watermarking algorithm for color image protection and authenticity: robust, not blind, and wavelet-based. The use of Discrete Wavelet Transform is motivated by good time-frequency features and a good match with Human Visual System directives. These two combined elements are important for building an invisible and robust watermark. Moreover our algorithm can work with any image, thanks to the step of pre-processing of the image that includes resize techniques that adapt to the size of the original image for Wavelet transform. The watermark signal is calculated in correlation with the image features and statistic properties. In the detection step we apply a re-synchronization between the original and watermarked image according to the Neyman-Pearson statistic criterion. Experimentation on a large set of different images has been shown to be resistant against geometric, filtering, and StirMark attacks with a low rate of false alarm.

  5. Scene correction (precision techniques) of ERTS sensor data using digital image processing techniques

    NASA Technical Reports Server (NTRS)

    Bernstein, R.

    1974-01-01

    Techniques have been developed, implemented, and evaluated to process ERTS Return Beam Vidicon (RBV) and Multispectral Scanner (MSS) sensor data using digital image processing techniques. The RBV radiometry has been corrected to remove shading effects, and the MSS geometry and radiometry have been corrected to remove internal and external radiometric and geometric errors. The results achieved show that geometric mapping accuracy of about one picture element RMS and two picture elements (maximum) can be achieved by the use of nine ground control points. Radiometric correction of MSS and RBV sensor data has been performed to eliminate striping and shading effects to about one count accuracy. Image processing times on general purpose computers of the IBM 370/145 to 168 class are in the range of 29 to 3.2 minutes per MSS scene (4 bands). Photographic images of the fully corrected and annotated scenes have been generated from the processed data and have demonstrated excellent quality and information extraction potential.

  6. A software to digital image processing to be used in the voxel phantom development.

    PubMed

    Vieira, J W; Lima, F R A

    2009-11-15

    Anthropomorphic models used in computational dosimetry, also denominated phantoms, are based on digital images recorded from scanning of real people by Computed Tomography (CT) or Magnetic Resonance Imaging (MRI). The voxel phantom construction requests computational processing for transformations of image formats, to compact two-dimensional (2-D) images forming of three-dimensional (3-D) matrices, image sampling and quantization, image enhancement, restoration and segmentation, among others. Hardly the researcher of computational dosimetry will find all these available abilities in single software, and almost always this difficulty presents as a result the decrease of the rhythm of his researches or the use, sometimes inadequate, of alternative tools. The need to integrate the several tasks mentioned above to obtain an image that can be used in an exposure computational model motivated the development of the Digital Image Processing (DIP) software, mainly to solve particular problems in Dissertations and Thesis developed by members of the Grupo de Pesquisa em Dosimetria Numérica (GDN/CNPq). Because of this particular objective, the software uses the Portuguese idiom in their implementations and interfaces. This paper presents the second version of the DIP, whose main changes are the more formal organization on menus and menu items, and menu for digital image segmentation. Currently, the DIP contains the menus Fundamentos, Visualizações, Domínio Espacial, Domínio de Frequências, Segmentações and Estudos. Each menu contains items and sub-items with functionalities that, usually, request an image as input and produce an image or an attribute in the output. The DIP reads edits and writes binary files containing the 3-D matrix corresponding to a stack of axial images from a given geometry that can be a human body or other volume of interest. It also can read any type of computational image and to make conversions. When the task involves only an output image

  7. Acquisition hardware for digital imaging.

    PubMed

    Widmer, William R

    2008-01-01

    Use of digital radiography is growing rapidly in veterinary medicine. Two basic digital imaging systems are available, computed radiography (CR) and direct digital radiography (DDR). Computed radiographic detectors use a two-step process for image capture and processing. Image capture is by X-ray sensitive phosphors in the image plate. The image plate reader transforms the latent phosphor image to light photons that are converted to an analog electrical signal. An analog to digital converter is used to digitize the electrical signal before computer analysis. Direct digital detectors provide digital data by direct readout after image capture--a reader unnecessary. Types of DDR detectors are flat panel detectors and charge coupled device (CCD) detectors. Flat panel detectors are composed of layers of semiconductors for image capture with transistor and microscopic circuitry embedded in a pixel array. Direct converting flat panel detectors convert incident X-rays directly into electrical charges. Indirect detectors convert X-rays to visible light, then to electrical charges. All flat panel detectors send a digitized electrical signal to a computer using a direct link. Charge coupled device detectors have a small chip similar to those used in digital cameras. A scintillator first converts X-rays to a light signal that is minified by an optical system before reaching the chip. The chip sends a digital signal directly to a computer. Both CR and DDR provide quality diagnostic images. CR is a mature technology while DDR is an emerging technology.

  8. Two dimensional recursive digital filters for near real time image processing

    NASA Technical Reports Server (NTRS)

    Olson, D.; Sherrod, E.

    1980-01-01

    A program was designed toward the demonstration of the feasibility of using two dimensional recursive digital filters for subjective image processing applications that require rapid turn around. The concept of the use of a dedicated minicomputer for the processor for this application was demonstrated. The minicomputer used was the HP1000 series E with a RTE 2 disc operating system and 32K words of memory. A Grinnel 256 x 512 x 8 bit display system was used to display the images. Sample images were provided by NASA Goddard on a 800 BPI, 9 track tape. Four 512 x 512 images representing 4 spectral regions of the same scene were provided. These images were filtered with enhancement filters developed during this effort.

  9. Application of digital image processing for the generation of voxels phantoms for Monte Carlo simulation.

    PubMed

    Boia, L S; Menezes, A F; Cardoso, M A C; da Rosa, L A R; Batista, D V S; Cardoso, S C; Silva, A X; Facure, A

    2012-01-01

    This paper presents the application of a computational methodology for optimizing the conversion of medical tomographic images in voxel anthropomorphic models for simulation of radiation transport using the MCNP code. A computational system was developed for digital image processing that compresses the information from the DICOM medical image before it is converted to the Scan2MCNP software input file for optimization of the image data. In order to validate the computational methodology, a radiosurgery treatment simulation was performed using the Alderson Rando phantom and the acquisition of DICOM images was performed. The simulation results were compared with data obtained with the BrainLab planning system. The comparison showed good agreement for three orthogonal treatment beams of (60)Co gamma radiation. The percentage differences were 3.07%, 0.77% and 6.15% for axial, coronal and sagital projections, respectively. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. Digital image processing techniques for detecting, quantifying and classifying plant diseases.

    PubMed

    Arnal Barbedo, Jayme Garcia

    2013-12-07

    This paper presents a survey on methods that use digital image processing techniques to detect, quantify and classify plant diseases from digital images in the visible spectrum. Although disease symptoms can manifest in any part of the plant, only methods that explore visible symptoms in leaves and stems were considered. This was done for two main reasons: to limit the length of the paper and because methods dealing with roots, seeds and fruits have some peculiarities that would warrant a specific survey. The selected proposals are divided into three classes according to their objective: detection, severity quantification, and classification. Each of those classes, in turn, are subdivided according to the main technical solution used in the algorithm. This paper is expected to be useful to researchers working both on vegetable pathology and pattern recognition, providing a comprehensive and accessible overview of this important field of research.

  11. Spatial analysis of ambient gamma dose equivalent rate data by means of digital image processing techniques.

    PubMed

    Szabó, Katalin Zsuzsanna; Jordan, Gyozo; Petrik, Attila; Horváth, Ákos; Szabó, Csaba

    2017-01-01

    A detailed ambient gamma dose equivalent rate mapping based on field measurements at ground level and at 1 m height was carried out at 142 sites in 80 × 90 km area in Pest County, Hungary. Detailed digital image processing analysis was carried out to identify and characterise spatial features such as outlying points, anomalous zones and linear edges in a smoothed TIN interpolated surface. The applied method proceeds from the simple shaded relief model and digital cross-sections to the more complex gradient magnitude and gradient direction maps, 2nd derivative profile curvature map, relief map and lineament density map. Each map is analysed for statistical characteristics and histogram-based image segmentation is used to delineate areas homogeneous with respect to the parameter values in these maps. Assessment of spatial anisotropy is implemented by 2D autocorrelogram and directional variogram analyses. The identified spatial features are related to underlying geological and tectonic conditions using GIS technology. Results show that detailed digital image processing is efficient in revealing the pattern present in field-measured ambient gamma dose equivalent rates and they are related to regional scale tectonic zones and surface sedimentary lithological conditions in the study area. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Digital image processing based mass flow rate measurement of gas/solid two-phase flow

    NASA Astrophysics Data System (ADS)

    Song, Ding; Peng, Lihui; Lu, Geng; Yang, Shiyuan; Yan, Yong

    2009-02-01

    With the rapid growth of the process industry, pneumatic conveying as a tool for the transportation of a wide variety of pulverized and granular materials has become widespread. In order to improve plant control and operational efficiency, it is essential to know the parameters of the particle flow. This paper presents a digital imaging based method which is capable of measuring multiple flow parameters, including volumetric concentration, velocity and mass flow rate of particles in the gas/solid two phase flow. The measurement system consists of a solid state laser for illumination, a low-cost CCD camera for particle image acquisition and a microcomputer with bespoke software for particle image processing. The measurements of particle velocity and volumetric concentration share the same sensing hardware but use different exposure time and different image processing methods. By controlling the exposure time of the camera a clear image and a motion blurred image are obtained respectively. The clear image is thresholded by OTSU method to identify the particles from the dark background so that the volumetric concentration is determined by calculating the ratio between the particle area and the total area. Particle velocity is derived from the motion blur length, which is estimated from the motion blurred images by using the travelling wave equation method. The mass flow rate of particles is calculated by combining the particle velocity and volumetric concentration. Simulation and experiment results indicate that the proposed method is promising for the measurement of multiple parameters of gas/solid two-phase flow.

  13. Utilization of Digital Image Processing In Process of Quality Control of The Primary Packaging of Drug Using Color Normalization Method

    NASA Astrophysics Data System (ADS)

    Erwanto, Danang; Arttini Dwi Prasetyowati, Sri; Nuryanto Budi Susila, Eka

    2017-04-01

    In the process of quality control, accuracy is required so that the improper drug packaging is not included into the next production process. The automatic inspection system using digital image processing can be applied to replace the manual inspection system done by humans. The image captured from the vision sensor is RGB image which is then converted into grayscale. The process of converting RGB image into grayscale image is performed using the color normalization method to spread the data of RGB colors at each pixel. From the software of image processing using the color normalization method that have been created, it shows grayscale images on the drug object which have degrees of gray higher than the grayscale image section of the background when the degree of the R, G or B color of drug is higher than the degree of the R, G, B color on the background of packaging. The determination of threshold value indicates that the binary image of the drug is white and a binary image of the background of drug packaging is black.

  14. Research on pairing method of chromosome of endangered amphioxus based on digital image processing technology

    NASA Astrophysics Data System (ADS)

    Li, Jinping; Jia, Hongwei; Mu, Hongshan; Tan, Hai

    2010-07-01

    This paper studies a new method for chromosome pairing of amphioxus using digital image processing technology, selects chromosome banding image of amphioxus Branchiostoma belcheri tsingtauense as experimental material, compares and analyzes objective data such as perimeter, long axis and short axis of the chromosome, and realizes chromosome pairing of amphioxus with Reference to band feature of Laplace and Sobel edge detection as pairing supplement. According to objective data obtained from the program, this method improves the subjective pairing method which uses image processing software to measure long arm and short arm of the chromosome. The results show that the pairing method is effective, accurate and practical. This study has important theoretical and practical significance for further study of chromosome gene mapping and cell genetics of amphioxus.

  15. Searching early bone metastasis on plain radiography by using digital imaging processing

    SciTech Connect

    Jaramillo-Nunez, A.; Perez-Meza, M.

    2012-10-23

    Some authors mention that it is not possible to detect early bone metastasis on plain radiography. In this work we use digital imaging processing to analyze three radiographs taken from a patient with bone metastasis discomfort on the right shoulder. The time period among the first and second radiography was approximately one month and between the first and the third one year. This procedure is a first approach in order to know if in this particular case it was possible to detect an early bone metastasis. The obtained results suggest that by carrying out a digital processing is possible to detect the metastasis since the radiography contains the information although visually it is not possible to observe it.

  16. Searching early bone metastasis on plain radiography by using digital imaging processing

    NASA Astrophysics Data System (ADS)

    Jaramillo-Núñez, A.; Pérez-Meza, M.

    2012-10-01

    Some authors mention that it is not possible to detect early bone metastasis on plain radiography. In this work we use digital imaging processing to analyze three radiographs taken from a patient with bone metastasis discomfort on the right shoulder. The time period among the first and second radiography was approximately one month and between the first and the third one year. This procedure is a first approach in order to know if in this particular case it was possible to detect an early bone metastasis. The obtained results suggest that by carrying out a digital processing is possible to detect the metastasis since the radiography contains the information although visually it is not possible to observe it.

  17. Fast extended focused imaging in digital holography using a graphics processing unit.

    PubMed

    Wang, Le; Zhao, Jianlin; Di, Jianglei; Jiang, Hongzhen

    2011-05-01

    We present a simple and effective method for reconstructing extended focused images in digital holography using a graphics processing unit (GPU). The Fresnel transform method is simplified by an algorithm named fast Fourier transform pruning with frequency shift. Then the pixel size consistency problem is solved by coordinate transformation and combining the subpixel resampling and the fast Fourier transform pruning with frequency shift. With the assistance of the GPU, we implemented an improved parallel version of this method, which obtained about a 300-500-fold speedup compared with central processing unit codes.

  18. Phenopix: a R package to process digital images of a vegetation cover

    NASA Astrophysics Data System (ADS)

    Filippa, Gianluca; Cremonese, Edoardo; Migliavacca, Mirco; Galvagno, Marta; Morra di Cella, Umberto; Richardson, Andrew

    2015-04-01

    Plant phenology is a globally recognized indicator of the effects of climate change on the terrestrial biosphere. Accordingly, new tools to automatically track the seasonal development of a vegetation cover are becoming available and more and more deployed. Among them, near-continuous digital images are being collected in several networks in the US, Europe, Asia and Australia in a range of different ecosystems, including agricultural lands, deciduous and evergreen forests, and grasslands. The growing scientific interest in vegetation image analysis highlights the need of easy to use, flexible and standardized processing techniques. In this contribution we illustrate a new open source package called "phenopix" written in R language that allows to process images of a vegetation cover. The main features include: (i) define of one or more areas of interest on an image and process pixel information within them, (ii) compute vegetation indexes based on red green and blue channels, (iii) fit a curve to the seasonal trajectory of vegetation indexes and extract relevant dates (aka thresholds) on the seasonal trajectory; (iv) analyze image pixels separately to extract spatially explicit phenological information. The utilities of the package will be illustrated in detail for two subalpine sites, a grassland and a larch stand at about 2000 m in the Italian Western Alps. The phenopix package is a cost free and easy-to-use tool that allows to process digital images of a vegetation cover in a standardized, flexible and reproducible way. The software is available for download at the R forge web site (r-forge.r-project.org/projects/phenopix/).

  19. Flame colour characterization in the visible and infrared spectrum using a digital camera and image processing

    NASA Astrophysics Data System (ADS)

    Huang, Hua-Wei; Zhang, Yang

    2008-08-01

    An attempt has been made to characterize the colour spectrum of methane flame under various burning conditions using RGB and HSV colour models instead of resolving the real physical spectrum. The results demonstrate that each type of flame has its own characteristic distribution in both the RGB and HSV space. It has also been observed that the averaged B and G values in the RGB model represent well the CH* and C*2 emission of methane premixed flame. Theses features may be utilized for flame measurement and monitoring. The great advantage of using a conventional camera for monitoring flame properties based on the colour spectrum is that it is readily available, easy to interface with a computer, cost effective and has certain spatial resolution. Furthermore, it has been demonstrated that a conventional digital camera is able to image flame not only in the visible spectrum but also in the infrared. This feature is useful in avoiding the problem of image saturation typically encountered in capturing the very bright sooty flames. As a result, further digital imaging processing and quantitative information extraction is possible. It has been identified that an infrared image also has its own distribution in both the RGB and HSV colour space in comparison with a flame image in the visible spectrum.

  20. Effect of image processing version on detection of non-calcification cancers in 2D digital mammography imaging

    NASA Astrophysics Data System (ADS)

    Warren, L. M.; Cooke, J.; Given-Wilson, R. M.; Wallis, M. G.; Halling-Brown, M.; Mackenzie, A.; Chakraborty, D. P.; Bosmans, H.; Dance, D. R.; Young, K. C.

    2013-03-01

    Image processing (IP) is the last step in the digital mammography imaging chain before interpretation by a radiologist. Each manufacturer has their own IP algorithm(s) and the appearance of an image after IP can vary greatly depending upon the algorithm and version used. It is unclear whether these differences can affect cancer detection. This work investigates the effect of IP on the detection of non-calcification cancers by expert observers. Digital mammography images for 190 patients were collected from two screening sites using Hologic amorphous selenium detectors. Eighty of these cases contained non-calcification cancers. The images were processed using three versions of IP from Hologic - default (full enhancement), low contrast (intermediate enhancement) and pseudo screen-film (no enhancement). Seven experienced observers inspected the images and marked the location of regions suspected to be non-calcification cancers assigning a score for likelihood of malignancy. This data was analysed using JAFROC analysis. The observers also scored the clinical interpretation of the entire case using the BSBR classification scale. This was analysed using ROC analysis. The breast density in the region surrounding each cancer and the number of times each cancer was detected were calculated. IP did not have a significant effect on the radiologists' judgment of the likelihood of malignancy of individual lesions or their clinical interpretation of the entire case. No correlation was found between number of times each cancer was detected and the density of breast tissue surrounding that cancer.

  1. Optical Image Classification Using Optical/digital Hybrid Image Processing Systems.

    NASA Astrophysics Data System (ADS)

    Li, Xiaoyang

    1990-01-01

    Offering parallel and real-time operations, optical image classification is becoming a general technique in the solution of real-life image classification problems. This thesis investigates several algorithms for optical realization. Compared to other statistical pattern recognition algorithms, the Kittler-Young transform can provide more discriminative feature spaces for image classification. We shall apply the Kittler-Young transform to image classification and implement it on optical systems. A feature selection criterion is designed for the application of the Kittler -Young transform to image classification. The realizations of the Kittler-Young transform on both a joint transform correlator and a matrix multiplier are successively conducted. Experiments of applying this technique to two-category and three-category problems are demonstrated. To combine the advantages of the statistical pattern recognition algorithms and the neural network models, processes using the two methods are studied. The Karhunen-Loeve Hopfield model is developed for image classification. This model has significant improvement in the system capacity and the capability of using image structures for more discriminative classification processes. As another such hybrid process, we propose the feature extraction perceptron. The application of feature extraction techniques to the perceptron shortens its learning time. An improved activation function of neurons (dynamic activation function), its design and updating rule for fast learning process and high space-bandwidth product image classification are also proposed. We have shortened by two-thirds the learning time on the feature extraction perceptron as compared with the original perceptron. By using this architecture, we have shown that the classification performs better than both the Kittler-Young transform and the original perceptron.

  2. Method of Digital Hologram Coding-Decoding and Holographic Image Processing Based on the Gabor Wavelet

    NASA Astrophysics Data System (ADS)

    Kozlova, A. S.

    2016-02-01

    Special features of an algorithm for coding-decoding of digital particle holograms and restoration of holographic particle images based on the Gabor wavelet are considered. The method involves the application of the decoded wavelet coefficients for the subsequent restoration of images from digital holograms. Results of approbation of the method to numerically calculated holograms and holograms of plankton particles are presented.

  3. DIGITAL PROCESSING TECHNIQUES FOR IMAGE MAPPING WITH LANDSAT TM AND SPOT SIMULATOR DATA.

    USGS Publications Warehouse

    Chavez, Pat S.; ,

    1984-01-01

    To overcome certain problems associated with the visual selection of Landsat TM bands for image mapping, the author used a quantitative technique that ranks the 20 possible three-band combinations based upon their information content. Standard deviations and correlation coefficients can be used to compute a value called the Optimum Index Factor (OIF) for each of the 20 possible combinations. SPOT simulator images were digitally processed and compared with Landsat-4 Thematic Mapper (TM) images covering a semi-arid region in northern Arizona and a highly vegetated urban area near Washington, D. C. Statistical comparisons indicate the more radiometric or color information exists in certain TM three-band combinations than in the three SPOT bands.

  4. Automated image processing of LANDSAT 2 digital data for watershed runoff prediction

    NASA Technical Reports Server (NTRS)

    Sasso, R. R.; Jensen, J. R.; Estes, J. E.

    1977-01-01

    The U.S. Soil Conservation Service (SCS) model for watershed runoff prediction uses soil and land cover information as its major drivers. Kern County Water Agency is implementing the SCS model to predict runoff for 10,400 sq cm of mountainous watershed in Kern County, California. The Remote Sensing Unit, University of California, Santa Barbara, was commissioned by KCWA to conduct a 230 sq cm feasibility study in the Lake Isabella, California region to evaluate remote sensing methodologies which could be ultimately extrapolated to the entire 10,400 sq cm Kern County watershed. Digital results indicate that digital image processing of Landsat 2 data will provide usable land cover required by KCWA for input to the SCS runoff model.

  5. Automated image processing of LANDSAT 2 digital data for watershed runoff prediction

    NASA Technical Reports Server (NTRS)

    Sasso, R. R.; Jensen, J. R.; Estes, J. E.

    1977-01-01

    The U.S. Soil Conservation Service (SCS) model for watershed runoff prediction uses soil and land cover information as its major drivers. Kern County Water Agency is implementing the SCS model to predict runoff for 10,400 sq cm of mountainous watershed in Kern County, California. The Remote Sensing Unit, University of California, Santa Barbara, was commissioned by KCWA to conduct a 230 sq cm feasibility study in the Lake Isabella, California region to evaluate remote sensing methodologies which could be ultimately extrapolated to the entire 10,400 sq cm Kern County watershed. Digital results indicate that digital image processing of Landsat 2 data will provide usable land cover required by KCWA for input to the SCS runoff model.

  6. Digital image processing in the SECURE concealed-object detection system

    NASA Astrophysics Data System (ADS)

    Smith, Steven W.

    1993-04-01

    A new technology has been developed for detecting explosives and other dangerous objects concealed under persons' clothing. The 'Subambient Exposure, Computer Utilized Reflected Energy' (SECURE) method uses a very low level of back-scattered x-rays in conjunction with digital image processing to produce an image of the person and any concealed objects. Image processing algorithms, used in the system are directed at presenting information to a human operator in the best possible manner for foreign object detection. These algorithms are viewed as being near optimum, and additional development is probably not justified. Algorithm development is needed in the area of automatic threat detection. This has the potential of reducing the invasion of privacy associated with having a security operator view each image. It also has the potential of reducing the serious problem of operator complacency. In one approach, the new algorithm must (1) recognize and isolate objects in the image, (2) discriminate between concealed objects and human anatomy, and (3) discriminate between dangerous and benign concealed objects. The images produced with the SECURE technology are extremely noisy due to the low levels of radiation used. Any algorithm developed must perform well in this noisy environment. Execution of the algorithm must be accomplished in less than a few seconds. Hardware to implement the algorithm must be of a complexity and cost compatible with the commercial SECURE system.

  7. Rocket engine plume diagnostics using video digitization and image processing - Analysis of start-up

    NASA Technical Reports Server (NTRS)

    Disimile, P. J.; Shoe, B.; Dhawan, A. P.

    1991-01-01

    Video digitization techniques have been developed to analyze the exhaust plume of the Space Shuttle Main Engine. Temporal averaging and a frame-by-frame analysis provide data used to evaluate the capabilities of image processing techniques for use as measurement tools. Capabilities include the determination of the necessary time requirement for the Mach disk to obtain a fully-developed state. Other results show the Mach disk tracks the nozzle for short time intervals, and that dominate frequencies exist for the nozzle and Mach disk movement.

  8. Performance Evaluation Method of Chemical Mechanical Polishing Pad Conditioner Using Digital Image Correlation Processing

    NASA Astrophysics Data System (ADS)

    Uneda, Michio; Omote, Tatsunori; Ishikawa, Ken-ichi; Ichikawa, Koichiro; Doi, Toshiro; Kurokawa, Syuhei; Ohnishi, Osamu

    2012-05-01

    In chemical mechanical polishing (CMP), conditioning is generally used for the regeneration of the pad surface texture. Currently, the performance evaluation of conditioners depends on the user's experience so that it is important to develop a novel quantitative evaluation method for conditioner performance. In this paper, we propose a novel evaluation method for conditioner performance using digital image correlation (DIC) processing. The proposed method can measure the in-plane micro-deformation distribution of the pad surface texture by conditioning. It is found that a pad surface deforms over 40 µm with conditioning and that the in-plane deformation value increases with a decrease in the mesh size of conditioner grains.

  9. Automated image processing of Landsat II digital data for watershed runoff prediction

    NASA Technical Reports Server (NTRS)

    Sasso, R. R.; Jensen, J. R.; Estes, J. E.

    1977-01-01

    Digital image processing of Landsat data from a 230 sq km area was examined as a possible means of generating soil cover information for use in the watershed runoff prediction of Kern County, California. The soil cover information included data on brush, grass, pasture lands and forests. A classification accuracy of 94% for the Landsat-based soil cover survey suggested that the technique could be applied to the watershed runoff estimate. However, problems involving the survey of complex mountainous environments may require further attention

  10. Rocket engine plume diagnostics using video digitization and image processing - Analysis of start-up

    NASA Technical Reports Server (NTRS)

    Disimile, P. J.; Shoe, B.; Dhawan, A. P.

    1991-01-01

    Video digitization techniques have been developed to analyze the exhaust plume of the Space Shuttle Main Engine. Temporal averaging and a frame-by-frame analysis provide data used to evaluate the capabilities of image processing techniques for use as measurement tools. Capabilities include the determination of the necessary time requirement for the Mach disk to obtain a fully-developed state. Other results show the Mach disk tracks the nozzle for short time intervals, and that dominate frequencies exist for the nozzle and Mach disk movement.

  11. Simulation and analysis of natural rain in a wind tunnel via digital image processing techniques

    NASA Technical Reports Server (NTRS)

    Aaron, K. M.; Hernan, M.; Parikh, P.; Sarohia, V.; Gharib, M.

    1986-01-01

    It is desired to simulate natural rain in a wind tunnel in order to investigate its influence on the aerodynamic characteristics of aircraft. Rain simulation nozzles have been developed and tested at JPL. Pulsed laser sheet illumination is used to photograph the droplets in the moving airstream. Digital image processing techniques are applied to these photographs for calculation of rain statistics to evaluate the performance of the nozzles. It is found that fixed hypodermic type nozzles inject too much water to simulate natural rain conditions. A modification uses two aerodynamic spinners to flex a tube in a pseudo-random fashion to distribute the water over a larger area.

  12. Image Processing

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Images are prepared from data acquired by the multispectral scanner aboard Landsat, which views Earth in four ranges of the electromagnetic spectrum, two visible bands and two infrared. Scanner picks up radiation from ground objects and converts the radiation signatures to digital signals, which are relayed to Earth and recorded on tape. Each tape contains "pixels" or picture elements covering a ground area; computerized equipment processes the tapes and plots each pixel, line be line to produce the basic image. Image can be further processed to correct sensor errors, to heighten contrast for feature emphasis or to enhance the end product in other ways. Key factor in conversion of digital data to visual form is precision of processing equipment. Jet Propulsion Laboratory prepared a digital mosaic that was plotted and enhanced by Optronics International, Inc. by use of the company's C-4300 Colorwrite, a high precision, high speed system which manipulates and analyzes digital data and presents it in visual form on film. Optronics manufactures a complete family of image enhancement processing systems to meet all users' needs. Enhanced imagery is useful to geologists, hydrologists, land use planners, agricultural specialists geographers and others.

  13. Digital image processing of nanometer-size metal particles on amorphous substrates

    NASA Technical Reports Server (NTRS)

    Soria, F.; Artal, P.; Bescos, J.; Heinemann, K.

    1989-01-01

    The task of differentiating very small metal aggregates supported on amorphous films from the phase contrast image features inherently stemming from the support is extremely difficult in the nanometer particle size range. Digital image processing was employed to overcome some of the ambiguities in evaluating such micrographs. It was demonstrated that such processing allowed positive particle detection and a limited degree of statistical size analysis even for micrographs where by bare eye examination the distribution between particles and erroneous substrate features would seem highly ambiguous. The smallest size class detected for Pd/C samples peaks at 0.8 nm. This size class was found in various samples prepared under different evaporation conditions and it is concluded that these particles consist of 'a magic number' of 13 atoms and have cubooctahedral or icosahedral crystal structure.

  14. Digital image processing of nanometer-size metal particles on amorphous substrates

    NASA Technical Reports Server (NTRS)

    Soria, F.; Artal, P.; Bescos, J.; Heinemann, K.

    1989-01-01

    The task of differentiating very small metal aggregates supported on amorphous films from the phase contrast image features inherently stemming from the support is extremely difficult in the nanometer particle size range. Digital image processing was employed to overcome some of the ambiguities in evaluating such micrographs. It was demonstrated that such processing allowed positive particle detection and a limited degree of statistical size analysis even for micrographs where by bare eye examination the distribution between particles and erroneous substrate features would seem highly ambiguous. The smallest size class detected for Pd/C samples peaks at 0.8 nm. This size class was found in various samples prepared under different evaporation conditions and it is concluded that these particles consist of 'a magic number' of 13 atoms and have cubooctahedral or icosahedral crystal structure.

  15. Surface-roughness measurement by digital processing of Nomarski phase-contrast images.

    PubMed

    Jabr, S N

    1985-11-01

    Surface roughnesses down to 0.1 nm rms were measured on low-reflectance polished glass and silica substrates by quantitative analysis of Nomarski differential phase-contrast images with a fast digital image processor. A measure of roughness was obtained from the standard deviation of intensities in the Nomarski image observed by a vidicon tube with linear response and digitized in real time.

  16. A novel pre-processing technique for improving image quality in digital breast tomosynthesis.

    PubMed

    Kim, Hyeongseok; Lee, Taewon; Hong, Joonpyo; Sabir, Sohail; Lee, Jung-Ryun; Choi, Young Wook; Kim, Hak Hee; Chae, Eun Young; Cho, Seungryong

    2017-02-01

    Nonlinear pre-reconstruction processing of the projection data in computed tomography (CT) where accurate recovery of the CT numbers is important for diagnosis is usually discouraged, for such a processing would violate the physics of image formation in CT. However, one can devise a pre-processing step to enhance detectability of lesions in digital breast tomosynthesis (DBT) where accurate recovery of the CT numbers is fundamentally impossible due to the incompleteness of the scanned data. Since the detection of lesions such as micro-calcifications and mass in breasts is the purpose of using DBT, it is justified that a technique producing higher detectability of lesions is a virtue. A histogram modification technique was developed in the projection data domain. Histogram of raw projection data was first divided into two parts: One for the breast projection data and the other for background. Background pixel values were set to a single value that represents the boundary between breast and background. After that, both histogram parts were shifted by an appropriate amount of offset and the histogram-modified projection data were log-transformed. Filtered-backprojection (FBP) algorithm was used for image reconstruction of DBT. To evaluate performance of the proposed method, we computed the detectability index for the reconstructed images from clinically acquired data. Typical breast border enhancement artifacts were greatly suppressed and the detectability of calcifications and masses was increased by use of the proposed method. Compared to a global threshold-based post-reconstruction processing technique, the proposed method produced images of higher contrast without invoking additional image artifacts. In this work, we report a novel pre-processing technique that improves detectability of lesions in DBT and has potential advantages over the global threshold-based post-reconstruction processing technique. The proposed method not only increased the lesion detectability

  17. Introduction of A New Toolbox for Processing Digital Images From Multiple Camera Networks: FMIPROT

    NASA Astrophysics Data System (ADS)

    Melih Tanis, Cemal; Nadir Arslan, Ali

    2017-04-01

    Webcam networks intended for scientific monitoring of ecosystems is providing digital images and other environmental data for various studies. Also, other types of camera networks can also be used for scientific purposes, e.g. usage of traffic webcams for phenological studies, camera networks for ski tracks and avalanche monitoring over mountains for hydrological studies. To efficiently harness the potential of these camera networks, easy to use software which can obtain and handle images from different networks having different protocols and standards is necessary. For the analyses of the images from webcam networks, numerous software packages are freely available. These software packages have different strong features not only for analyzing but also post processing digital images. But specifically for the ease of use, applicability and scalability, a different set of features could be added. Thus, a more customized approach would be of high value, not only for analyzing images of comprehensive camera networks, but also considering the possibility to create operational data extraction and processing with an easy to use toolbox. At this paper, we introduce a new toolbox, entitled; Finnish Meteorological Institute Image PROcessing Tool (FMIPROT) which a customized approach is followed. FMIPROT has currently following features: • straightforward installation, • no software dependencies that require as extra installations, • communication with multiple camera networks, • automatic downloading and handling images, • user friendly and simple user interface, • data filtering, • visualizing results on customizable plots, • plugins; allows users to add their own algorithms. Current image analyses in FMIPROT include "Color Fraction Extraction" and "Vegetation Indices". The analysis of color fraction extraction is calculating the fractions of the colors in a region of interest, for red, green and blue colors along with brightness and luminance parameters. The

  18. Applications of digital image processing XV; Proceedings of the Meeting, San Diego, CA, July 21-24, 1992

    NASA Astrophysics Data System (ADS)

    Tescher, Andrew G.

    1993-01-01

    Recent advances in digital image processing are addressed, focusing on image representations and models; systems and implementations; image understanding issues; algorithms; nonlinear technology for signal processing, communication, and control; image coding and transmission; innovative applications; and contributions of general interest. Particular attention is given to subpixel resolution for target tracking, endoscopic inspection and measurement, a technique of color image processing to enhance the cytomorphological deformation, improved moment invariants for shape discrimination, model adaptive optimal image restoration, noise reduction for chaotic data by geometric projection, a comparison of image coding techniques with a picture quality scale, a tissue characterization by texture analysis of ultrasonic images, a novel approach to human face recognition, and digital filtering methods used in eliminating diffraction halo of speckle interferograms. (No individual items are abstracted in this volume)

  19. Classification-based summation of cerebral digital subtraction angiography series for image post-processing algorithms

    NASA Astrophysics Data System (ADS)

    Schuldhaus, D.; Spiegel, M.; Redel, T.; Polyanskaya, M.; Struffert, T.; Hornegger, J.; Doerfler, A.

    2011-03-01

    X-ray-based 2D digital subtraction angiography (DSA) plays a major role in the diagnosis, treatment planning and assessment of cerebrovascular disease, i.e. aneurysms, arteriovenous malformations and intracranial stenosis. DSA information is increasingly used for secondary image post-processing such as vessel segmentation, registration and comparison to hemodynamic calculation using computational fluid dynamics. Depending on the amount of injected contrast agent and the duration of injection, these DSA series may not exhibit one single DSA image showing the entire vessel tree. The interesting information for these algorithms, however, is usually depicted within a few images. If these images would be combined into one image the complexity of segmentation or registration methods using DSA series would drastically decrease. In this paper, we propose a novel method automatically splitting a DSA series into three parts, i.e. mask, arterial and parenchymal phase, to provide one final image showing all important vessels with less noise and moving artifacts. This final image covers all arterial phase images, either by image summation or by taking the minimum intensities. The phase classification is done by a two-step approach. The mask/arterial phase border is determined by a Perceptron-based method trained from a set of DSA series. The arterial/parenchymal phase border is specified by a threshold-based method. The evaluation of the proposed method is two-sided: (1) comparison between automatic and medical expert-based phase selection and (2) the quality of the final image is measured by gradient magnitudes inside the vessels and signal-to-noise (SNR) outside. Experimental results show a match between expert and automatic phase separation of 93%/50% and an average SNR increase of up to 182% compared to summing up the entire series.

  20. Classification-based summation of cerebral digital subtraction angiography series for image post-processing algorithms.

    PubMed

    Schuldhaus, D; Spiegel, M; Redel, T; Polyanskaya, M; Struffert, T; Hornegger, J; Doerfler, A

    2011-03-21

    X-ray-based 2D digital subtraction angiography (DSA) plays a major role in the diagnosis, treatment planning and assessment of cerebrovascular disease, i.e. aneurysms, arteriovenous malformations and intracranial stenosis. DSA information is increasingly used for secondary image post-processing such as vessel segmentation, registration and comparison to hemodynamic calculation using computational fluid dynamics. Depending on the amount of injected contrast agent and the duration of injection, these DSA series may not exhibit one single DSA image showing the entire vessel tree. The interesting information for these algorithms, however, is usually depicted within a few images. If these images would be combined into one image the complexity of segmentation or registration methods using DSA series would drastically decrease. In this paper, we propose a novel method automatically splitting a DSA series into three parts, i.e. mask, arterial and parenchymal phase, to provide one final image showing all important vessels with less noise and moving artifacts. This final image covers all arterial phase images, either by image summation or by taking the minimum intensities. The phase classification is done by a two-step approach. The mask/arterial phase border is determined by a Perceptron-based method trained from a set of DSA series. The arterial/parenchymal phase border is specified by a threshold-based method. The evaluation of the proposed method is two-sided: (1) comparison between automatic and medical expert-based phase selection and (2) the quality of the final image is measured by gradient magnitudes inside the vessels and signal-to-noise (SNR) outside. Experimental results show a match between expert and automatic phase separation of 93%/50% and an average SNR increase of up to 182% compared to summing up the entire series.

  1. Image processing in digital pathology: an opportunity to solve inter-batch variability of immunohistochemical staining

    NASA Astrophysics Data System (ADS)

    van Eycke, Yves-Rémi; Allard, Justine; Salmon, Isabelle; Debeir, Olivier; Decaestecker, Christine

    2017-02-01

    Immunohistochemistry (IHC) is a widely used technique in pathology to evidence protein expression in tissue samples. However, this staining technique is known for presenting inter-batch variations. Whole slide imaging in digital pathology offers a possibility to overcome this problem by means of image normalisation techniques. In the present paper we propose a methodology to objectively evaluate the need of image normalisation and to identify the best way to perform it. This methodology uses tissue microarray (TMA) materials and statistical analyses to evidence the possible variations occurring at colour and intensity levels as well as to evaluate the efficiency of image normalisation methods in correcting them. We applied our methodology to test different methods of image normalisation based on blind colour deconvolution that we adapted for IHC staining. These tests were carried out for different IHC experiments on different tissue types and targeting different proteins with different subcellular localisations. Our methodology enabled us to establish and to validate inter-batch normalization transforms which correct the non-relevant IHC staining variations. The normalised image series were then processed to extract coherent quantitative features characterising the IHC staining patterns.

  2. On line measurement of lag angle in optical fiber winding using digital image processing technology

    NASA Astrophysics Data System (ADS)

    Ma, Baoji; Zhu, Yuquan; Jin, Xiaoli; Zhang, Jun

    2008-12-01

    During the optical fiber winding, larger or smaller lag angle would lead to superposition or spacing winding which would seriously influence the quality and stability of optical fiber bobbin. So the precise measurement and control of the lag angle was a key technique in optical fiber precise winding. Based on computer digital image technology, a new measurement scheme was proposed. According to the measurement requests, hardware of the image collection system and the image processing system were designed. By means of the image collection system and the designed program, the lag angle image was successfully collected. The resolution and efficiency of the Hough transform and the concentric cirque seeking method for image recognition were tested. The results showed that the efficiency of the Hough transform and the concentric cirque seeking method is low. So an improved Hough transform method was developed and the efficiency was numerically tested. The results showed that the improved Hough transform method was much more efficient and 0.1° measurement error of the lag angle can be achieved.

  3. Image processing in digital pathology: an opportunity to solve inter-batch variability of immunohistochemical staining

    PubMed Central

    Van Eycke, Yves-Rémi; Allard, Justine; Salmon, Isabelle; Debeir, Olivier; Decaestecker, Christine

    2017-01-01

    Immunohistochemistry (IHC) is a widely used technique in pathology to evidence protein expression in tissue samples. However, this staining technique is known for presenting inter-batch variations. Whole slide imaging in digital pathology offers a possibility to overcome this problem by means of image normalisation techniques. In the present paper we propose a methodology to objectively evaluate the need of image normalisation and to identify the best way to perform it. This methodology uses tissue microarray (TMA) materials and statistical analyses to evidence the possible variations occurring at colour and intensity levels as well as to evaluate the efficiency of image normalisation methods in correcting them. We applied our methodology to test different methods of image normalisation based on blind colour deconvolution that we adapted for IHC staining. These tests were carried out for different IHC experiments on different tissue types and targeting different proteins with different subcellular localisations. Our methodology enabled us to establish and to validate inter-batch normalization transforms which correct the non-relevant IHC staining variations. The normalised image series were then processed to extract coherent quantitative features characterising the IHC staining patterns. PMID:28220842

  4. Image processing in digital pathology: an opportunity to solve inter-batch variability of immunohistochemical staining.

    PubMed

    Van Eycke, Yves-Rémi; Allard, Justine; Salmon, Isabelle; Debeir, Olivier; Decaestecker, Christine

    2017-02-21

    Immunohistochemistry (IHC) is a widely used technique in pathology to evidence protein expression in tissue samples. However, this staining technique is known for presenting inter-batch variations. Whole slide imaging in digital pathology offers a possibility to overcome this problem by means of image normalisation techniques. In the present paper we propose a methodology to objectively evaluate the need of image normalisation and to identify the best way to perform it. This methodology uses tissue microarray (TMA) materials and statistical analyses to evidence the possible variations occurring at colour and intensity levels as well as to evaluate the efficiency of image normalisation methods in correcting them. We applied our methodology to test different methods of image normalisation based on blind colour deconvolution that we adapted for IHC staining. These tests were carried out for different IHC experiments on different tissue types and targeting different proteins with different subcellular localisations. Our methodology enabled us to establish and to validate inter-batch normalization transforms which correct the non-relevant IHC staining variations. The normalised image series were then processed to extract coherent quantitative features characterising the IHC staining patterns.

  5. Image-Processing Educator

    NASA Technical Reports Server (NTRS)

    Gunther, F. J.

    1986-01-01

    Apple Image-Processing Educator (AIPE) explores ability of microcomputers to provide personalized computer-assisted instruction (CAI) in digital image processing of remotely sensed images. AIPE is "proof-of-concept" system, not polished production system. User-friendly prompts provide access to explanations of common features of digital image processing and of sample programs that implement these features.

  6. Integration of digital signal processing technologies with pulsed electron paramagnetic resonance imaging

    PubMed Central

    Pursley, Randall H.; Salem, Ghadi; Devasahayam, Nallathamby; Subramanian, Sankaran; Koscielniak, Janusz; Krishna, Murali C.; Pohida, Thomas J.

    2006-01-01

    The integration of modern data acquisition and digital signal processing (DSP) technologies with Fourier transform electron paramagnetic resonance (FT-EPR) imaging at radiofrequencies (RF) is described. The FT-EPR system operates at a Larmor frequency (Lf) of 300 MHz to facilitate in vivo studies. This relatively low frequency Lf, in conjunction with our ~10 MHz signal bandwidth, enables the use of direct free induction decay time-locked subsampling (TLSS). This particular technique provides advantages by eliminating the traditional analog intermediate frequency downconversion stage along with the corresponding noise sources. TLSS also results in manageable sample rates that facilitate the design of DSP-based data acquisition and image processing platforms. More specifically, we utilize a high-speed field programmable gate array (FPGA) and a DSP processor to perform advanced real-time signal and image processing. The migration to a DSP-based configuration offers the benefits of improved EPR system performance, as well as increased adaptability to various EPR system configurations (i.e., software configurable systems instead of hardware reconfigurations). The required modifications to the FT-EPR system design are described, with focus on the addition of DSP technologies including the application-specific hardware, software, and firmware developed for the FPGA and DSP processor. The first results of using real-time DSP technologies in conjunction with direct detection bandpass sampling to implement EPR imaging at RF frequencies are presented. PMID:16243552

  7. Semi-automated Digital Imaging and Processing System for Measuring Lake Ice Thickness

    NASA Astrophysics Data System (ADS)

    Singh, Preetpal

    to detect equipment failure and identify defective products at the assembly line. The research work in this thesis combines machine vision and image processing technology to build a digital imaging and processing system for monitoring and measuring lake ice thickness in real time. An ultra-compact USB camera is programmed to acquire and transmit high resolution imagery for processing with MATLAB Image Processing toolbox. The image acquisition and transmission process is fully automated; image analysis is semi-automated and requires limited user input. Potential design changes to the prototype and ideas on fully automating the imaging and processing procedure are presented to conclude this research work.

  8. [Measuring the contrast resolution limits of human vision based on the modern digital image processing].

    PubMed

    Wang, Zhifang; Liu, Yuhong; Wang, Ying; Li, Hong; Li, Zhangyong; Zhao, Zhiqiang; Xie, Zhengxiang

    2008-10-01

    In the literatures on the human vision physiology and physics, there were reports about space resolution limit of 1' visual angle, frequency resolution limit of 5 nm and time resolution limit of 0.1" of human vision. However, there has been no report about the contrast resolution limit of human vision,especially the report of measuring method and result about the contrast resolution limit of human vision based on the modern digital image processing. Here we report a modern method for measuring the contrast resolution limit of human vision based on computer digital image processing technology, and we present the measured results and their mathematical models. The function relationships of contrast resolution limit varying with background gray in a photopic or a scotopic sights were illuminated respectively. It can be expected that such investigations with regard to human vision will establish the physiological foundation of the theories and techniques in hiding bodies and hiding figures (stealth), in anti-hiding bodies and anti-hiding figures, in the night vision system independent of infrared, as well as in their relative industries.

  9. Design criteria for a multiple input land use system. [digital image processing techniques

    NASA Technical Reports Server (NTRS)

    Billingsley, F. C.; Bryant, N. A.

    1975-01-01

    A design is presented that proposes the use of digital image processing techniques to interface existing geocoded data sets and information management systems with thematic maps and remote sensed imagery. The basic premise is that geocoded data sets can be referenced to a raster scan that is equivalent to a grid cell data set, and that images taken of thematic maps or from remote sensing platforms can be converted to a raster scan. A major advantage of the raster format is that x, y coordinates are implicitly recognized by their position in the scan, and z values can be treated as Boolean layers in a three-dimensional data space. Such a system permits the rapid incorporation of data sets, rapid comparison of data sets, and adaptation to variable scales by resampling the raster scans.

  10. Design criteria for a multiple input land use system. [digital image processing techniques

    NASA Technical Reports Server (NTRS)

    Billingsley, F. C.; Bryant, N. A.

    1975-01-01

    A design is presented that proposes the use of digital image processing techniques to interface existing geocoded data sets and information management systems with thematic maps and remote sensed imagery. The basic premise is that geocoded data sets can be referenced to a raster scan that is equivalent to a grid cell data set, and that images taken of thematic maps or from remote sensing platforms can be converted to a raster scan. A major advantage of the raster format is that x, y coordinates are implicitly recognized by their position in the scan, and z values can be treated as Boolean layers in a three-dimensional data space. Such a system permits the rapid incorporation of data sets, rapid comparison of data sets, and adaptation to variable scales by resampling the raster scans.

  11. Man-machine interactive imaging and data processing using high-speed digital mass storage

    NASA Technical Reports Server (NTRS)

    Alsberg, H.; Nathan, R.

    1975-01-01

    The role of vision in teleoperation has been recognized as an important element in the man-machine control loop. In most applications of remote manipulation, direct vision cannot be used. To overcome this handicap, the human operator's control capabilities are augmented by a television system. This medium provides a practical and useful link between workspace and the control station from which the operator perform his tasks. Human performance deteriorates when the images are degraded as a result of instrumental and transmission limitations. Image enhancement is used to bring out selected qualities in a picture to increase the perception of the observer. A general purpose digital computer, an extensive special purpose software system is used to perform an almost unlimited repertoire of processing operations.

  12. Quantitative Assessment of Mouse Mammary Gland Morphology Using Automated Digital Image Processing and TEB Detection.

    PubMed

    Blacher, Silvia; Gérard, Céline; Gallez, Anne; Foidart, Jean-Michel; Noël, Agnès; Péqueux, Christel

    2016-04-01

    The assessment of rodent mammary gland morphology is largely used to study the molecular mechanisms driving breast development and to analyze the impact of various endocrine disruptors with putative pathological implications. In this work, we propose a methodology relying on fully automated digital image analysis methods including image processing and quantification of the whole ductal tree and of the terminal end buds as well. It allows to accurately and objectively measure both growth parameters and fine morphological glandular structures. Mammary gland elongation was characterized by 2 parameters: the length and the epithelial area of the ductal tree. Ductal tree fine structures were characterized by: 1) branch end-point density, 2) branching density, and 3) branch length distribution. The proposed methodology was compared with quantification methods classically used in the literature. This procedure can be transposed to several software and thus largely used by scientists studying rodent mammary gland morphology.

  13. Digital imaging in pathology.

    PubMed

    Park, Seung; Pantanowitz, Liron; Parwani, Anil Vasdev

    2012-12-01

    Advances in computing speed and power have made a pure digital work flow for pathology. New technologies such as whole slide imaging (WSI), multispectral image analysis, and algorithmic image searching seem poised to fundamentally change the way in which pathology is practiced. This article provides the practicing pathologist with a primer on digital imaging. Building on this primer, the current state of the art concerning digital imaging in pathology is described. Emphasis is placed on WSI and its ramifications, showing how it is useful in both anatomic (histology, cytopathology) and clinical (hematopathology) pathology. Future trends are also extrapolated.

  14. Automated identification of copepods using digital image processing and artificial neural network

    PubMed Central

    2015-01-01

    Background Copepods are planktonic organisms that play a major role in the marine food chain. Studying the community structure and abundance of copepods in relation to the environment is essential to evaluate their contribution to mangrove trophodynamics and coastal fisheries. The routine identification of copepods can be very technical, requiring taxonomic expertise, experience and much effort which can be very time-consuming. Hence, there is an urgent need to introduce novel methods and approaches to automate identification and classification of copepod specimens. This study aims to apply digital image processing and machine learning methods to build an automated identification and classification technique. Results We developed an automated technique to extract morphological features of copepods' specimen from captured images using digital image processing techniques. An Artificial Neural Network (ANN) was used to classify the copepod specimens from species Acartia spinicauda, Bestiolina similis, Oithona aruensis, Oithona dissimilis, Oithona simplex, Parvocalanus crassirostris, Tortanus barbatus and Tortanus forcipatus based on the extracted features. 60% of the dataset was used for a two-layer feed-forward network training and the remaining 40% was used as testing dataset for system evaluation. Our approach demonstrated an overall classification accuracy of 93.13% (100% for A. spinicauda, B. similis and O. aruensis, 95% for T. barbatus, 90% for O. dissimilis and P. crassirostris, 85% for O. similis and T. forcipatus). Conclusions The methods presented in this study enable fast classification of copepods to the species level. Future studies should include more classes in the model, improving the selection of features, and reducing the time to capture the copepod images. PMID:26678287

  15. Automated identification of copepods using digital image processing and artificial neural network.

    PubMed

    Leow, Lee Kien; Chew, Li-Lee; Chong, Ving Ching; Dhillon, Sarinder Kaur

    2015-01-01

    Copepods are planktonic organisms that play a major role in the marine food chain. Studying the community structure and abundance of copepods in relation to the environment is essential to evaluate their contribution to mangrove trophodynamics and coastal fisheries. The routine identification of copepods can be very technical, requiring taxonomic expertise, experience and much effort which can be very time-consuming. Hence, there is an urgent need to introduce novel methods and approaches to automate identification and classification of copepod specimens. This study aims to apply digital image processing and machine learning methods to build an automated identification and classification technique. We developed an automated technique to extract morphological features of copepods' specimen from captured images using digital image processing techniques. An Artificial Neural Network (ANN) was used to classify the copepod specimens from species Acartia spinicauda, Bestiolina similis, Oithona aruensis, Oithona dissimilis, Oithona simplex, Parvocalanus crassirostris, Tortanus barbatus and Tortanus forcipatus based on the extracted features. 60% of the dataset was used for a two-layer feed-forward network training and the remaining 40% was used as testing dataset for system evaluation. Our approach demonstrated an overall classification accuracy of 93.13% (100% for A. spinicauda, B. similis and O. aruensis, 95% for T. barbatus, 90% for O. dissimilis and P. crassirostris, 85% for O. similis and T. forcipatus). The methods presented in this study enable fast classification of copepods to the species level. Future studies should include more classes in the model, improving the selection of features, and reducing the time to capture the copepod images.

  16. Image processing can cause some malignant soft-tissue lesions to be missed in digital mammography images.

    PubMed

    Warren, L M; Halling-Brown, M D; Looney, P T; Dance, D R; Wallis, M G; Given-Wilson, R M; Wilkinson, L; McAvinchey, R; Young, K C

    2017-09-01

    To investigate the effect of image processing on cancer detection in mammography. An observer study was performed using 349 digital mammography images of women with normal breasts, calcification clusters, or soft-tissue lesions including 191 subtle cancers. Images underwent two types of processing: FlavourA (standard) and FlavourB (added enhancement). Six observers located features in the breast they suspected to be cancerous (4,188 observations). Data were analysed using jackknife alternative free-response receiver operating characteristic (JAFROC) analysis. Characteristics of the cancers detected with each image processing type were investigated. For calcifications, the JAFROC figure of merit (FOM) was equal to 0.86 for both types of image processing. For soft-tissue lesions, the JAFROC FOM were better for FlavourA (0.81) than FlavourB (0.78); this difference was significant (p=0.001). Using FlavourA a greater number of cancers of all grades and sizes were detected than with FlavourB. FlavourA improved soft-tissue lesion detection in denser breasts (p=0.04 when volumetric density was over 7.5%) CONCLUSIONS: The detection of malignant soft-tissue lesions (which were primarily invasive) was significantly better with FlavourA than FlavourB image processing. This is despite FlavourB having a higher contrast appearance often preferred by radiologists. It is important that clinical choice of image processing is based on objective measures. Copyright © 2017 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

  17. Digital Image Access & Retrieval.

    ERIC Educational Resources Information Center

    Heidorn, P. Bryan, Ed.; Sandore, Beth, Ed.

    Recent technological advances in computing and digital imaging technology have had immediate and permanent consequences for visual resource collections. Libraries are involved in organizing and managing large visual resource collections. The central challenges in working with digital image collections mirror those that libraries have sought to…

  18. Digital Image Access & Retrieval.

    ERIC Educational Resources Information Center

    Heidorn, P. Bryan, Ed.; Sandore, Beth, Ed.

    Recent technological advances in computing and digital imaging technology have had immediate and permanent consequences for visual resource collections. Libraries are involved in organizing and managing large visual resource collections. The central challenges in working with digital image collections mirror those that libraries have sought to…

  19. An online detection system for aggregate sizes and shapes based on digital image processing

    NASA Astrophysics Data System (ADS)

    Yang, Jianhong; Chen, Sijia

    2016-07-01

    Traditional aggregate size measuring methods are time-consuming, taxing, and do not deliver online measurements. A new online detection system for determining aggregate size and shape based on a digital camera with a charge-coupled device, and subsequent digital image processing, have been developed to overcome these problems. The system captures images of aggregates while falling and flat lying. Using these data, the particle size and shape distribution can be obtained in real time. Here, we calibrate this method using standard globules. Our experiments show that the maximum particle size distribution error was only 3 wt%, while the maximum particle shape distribution error was only 2 wt% for data derived from falling aggregates, having good dispersion. In contrast, the data for flat-lying aggregates had a maximum particle size distribution error of 12 wt%, and a maximum particle shape distribution error of 10 wt%; their accuracy was clearly lower than for falling aggregates. However, they performed well for single-graded aggregates, and did not require a dispersion device. Our system is low-cost and easy to install. It can successfully achieve online detection of aggregate size and shape with good reliability, and it has great potential for aggregate quality assurance.

  20. An online detection system for aggregate sizes and shapes based on digital image processing

    NASA Astrophysics Data System (ADS)

    Yang, Jianhong; Chen, Sijia

    2017-02-01

    Traditional aggregate size measuring methods are time-consuming, taxing, and do not deliver online measurements. A new online detection system for determining aggregate size and shape based on a digital camera with a charge-coupled device, and subsequent digital image processing, have been developed to overcome these problems. The system captures images of aggregates while falling and flat lying. Using these data, the particle size and shape distribution can be obtained in real time. Here, we calibrate this method using standard globules. Our experiments show that the maximum particle size distribution error was only 3 wt%, while the maximum particle shape distribution error was only 2 wt% for data derived from falling aggregates, having good dispersion. In contrast, the data for flat-lying aggregates had a maximum particle size distribution error of 12 wt%, and a maximum particle shape distribution error of 10 wt%; their accuracy was clearly lower than for falling aggregates. However, they performed well for single-graded aggregates, and did not require a dispersion device. Our system is low-cost and easy to install. It can successfully achieve online detection of aggregate size and shape with good reliability, and it has great potential for aggregate quality assurance.

  1. Application of three-dimensional digital image processing for reconstruction of microstructural volume from serial sections

    SciTech Connect

    Tewari, A.; Gokhale, A.M.

    2000-03-01

    Three-dimensional digital image processing is useful for reconstruction of microstructural volume from a stack of serial sections. Application of this technique is demonstrated via reconstruction of a volume segment of the liquid-phase sintered microstructure of a tungsten heavy alloy processed in the microgravity environment of NASA's space shuttle, Columbia. Ninety serial sections (approximately one micrometer apart) were used for reconstruction of the three-dimensional microstructure. The three-dimensional microstructural reconstruction clearly revealed that the tungsten grains are almost completely connected in three-dimensional space. Both the matrix and the grains are topologically co-continuous, although the alloy was liquid-phase sintered in microgravity. Therefore, absence of gravity did not produced a microstructure consisting of discrete isolated W grains uniformly dispersed in the liquid Ni-Fe alloy matrix at the sintering temperature.

  2. Digital radiography image quality: image acquisition.

    PubMed

    Williams, Mark B; Krupinski, Elizabeth A; Strauss, Keith J; Breeden, William K; Rzeszotarski, Mark S; Applegate, Kimberly; Wyatt, Margaret; Bjork, Sandra; Seibert, J Anthony

    2007-06-01

    This article on digital radiography image acquisition is the first of two articles written as part of an intersociety effort to establish image quality standards for digital and computed radiography. The topic of the other paper is digital radiography image processing and display. The articles were developed collaboratively by the ACR, the American Association of Physicists in Medicine, and the Society for Imaging Informatics in Medicine. Increasingly, medical imaging and patient information are being managed using digital data during acquisition, transmission, storage, display, interpretation, and consultation. Data management during each of these operations has a direct impact on the quality of patient care. These articles describe what is known to improve image quality for digital and computed radiography and make recommendations on optimal acquisition, processing, and display. The practice of digital radiography is a rapidly evolving technology that will require the timely revision of any guidelines and standards. This document provides a basis for the technologies available today in clinical practice and may be useful in guiding the future clinical practice of digital radiography.

  3. Harmonisation of the appearance of digital radiographs from different vendors by means of common external image processing.

    PubMed

    Larsson, Lars; Båth, Magnus; Engman, Eva-Lena; Månsson, Lars Gunnar

    2010-01-01

    The aim of the present study was to evaluate the use of common external image processing to compensate for differences in appearance between digital X-ray images from different vendors. Twenty posteroanterior chest radiographs were collected from each of three different modalities from different vendors (GE, Siemens and Canon) with vendor-specific image processing applied. The images were also extracted with neutral process parameters and processed with external image-processing software. Six experienced radiologists rated the quality and the similarity of the images with the original Siemens images. The externally processed GE images were rated of higher quality than the original GE images and more similar to the original Siemens images (p < 0.001). The opposite was obtained for the Canon images. The externally processed Siemens images were rated of similar quality as the original images. The present study indicates the possibility of using common external image processing to harmonise the appearance of images from different vendors, although the exposure parameters may need to be adjusted for individual vendors.

  4. Image processing in astronomy

    NASA Astrophysics Data System (ADS)

    Berry, Richard

    1994-04-01

    Today's personal computers are more powerful than the mainframes that processed images during the early days of space exploration. We have entered an age in which anyone can do image processing. Topics covering the following aspects of image processing are discussed: digital-imaging basics, image calibration, image analysis, scaling, spatial enhancements, and compositing.

  5. A 'user friendly' geographic information system in a color interactive digital image processing system environment

    NASA Technical Reports Server (NTRS)

    Campbell, W. J.; Goldberg, M.

    1982-01-01

    NASA's Eastern Regional Remote Sensing Applications Center (ERRSAC) has recognized the need to accommodate spatial analysis techniques in its remote sensing technology transfer program. A computerized Geographic Information System to incorporate remotely sensed data, specifically Landsat, with other relevant data was considered a realistic approach to address a given resource problem. Questions arose concerning the selection of a suitable available software system to demonstrate, train, and undertake demonstration projects with ERRSAC's user community. The very specific requirements for such a system are discussed. The solution found involved the addition of geographic information processing functions to the Interactive Digital Image Manipulation System (IDIMS). Details regarding the functions of the new integrated system are examined along with the characteristics of the software.

  6. A 'user friendly' geographic information system in a color interactive digital image processing system environment

    NASA Technical Reports Server (NTRS)

    Campbell, W. J.; Goldberg, M.

    1982-01-01

    NASA's Eastern Regional Remote Sensing Applications Center (ERRSAC) has recognized the need to accommodate spatial analysis techniques in its remote sensing technology transfer program. A computerized Geographic Information System to incorporate remotely sensed data, specifically Landsat, with other relevant data was considered a realistic approach to address a given resource problem. Questions arose concerning the selection of a suitable available software system to demonstrate, train, and undertake demonstration projects with ERRSAC's user community. The very specific requirements for such a system are discussed. The solution found involved the addition of geographic information processing functions to the Interactive Digital Image Manipulation System (IDIMS). Details regarding the functions of the new integrated system are examined along with the characteristics of the software.

  7. [Film-less digital x-ray image processing--new prospects with the RadioVisioGraphy equipment].

    PubMed

    Mairgünther, R H

    1994-01-01

    Due to a new removable and compatible mass storage media, the ultimate model of the RadioVisioGraphy (RVG) system for X-ray recording without films offers an adequate possibility to store images as well as an easy way to transfer these data to other personal computers for digital image processing. By experiment we demonstrated a digital image subtraction procedure with public domain software, simulating a situation before and after apicoectomy. The result shows a good quality with a favourable relation between signal and noise.

  8. Automated identification of Monogeneans using digital image processing and K-nearest neighbour approaches.

    PubMed

    Yousef Kalafi, Elham; Tan, Wooi Boon; Town, Christopher; Dhillon, Sarinder Kaur

    2016-12-22

    Monogeneans are flatworms (Platyhelminthes) that are primarily found on gills and skin of fishes. Monogenean parasites have attachment appendages at their haptoral regions that help them to move about the body surface and feed on skin and gill debris. Haptoral attachment organs consist of sclerotized hard parts such as hooks, anchors and marginal hooks. Monogenean species are differentiated based on their haptoral bars, anchors, marginal hooks, reproductive parts' (male and female copulatory organs) morphological characters and soft anatomical parts. The complex structure of these diagnostic organs and also their overlapping in microscopic digital images are impediments for developing fully automated identification system for monogeneans (LNCS 7666:256-263, 2012), (ISDA; 457-462, 2011), (J Zoolog Syst Evol Res 52(2): 95-99. 2013;). In this study images of hard parts of the haptoral organs such as bars and anchors are used to develop a fully automated identification technique for monogenean species identification by implementing image processing techniques and machine learning methods. Images of four monogenean species namely Sinodiplectanotrema malayanus, Trianchoratus pahangensis, Metahaliotrema mizellei and Metahaliotrema sp. (undescribed) were used to develop an automated technique for identification. K-nearest neighbour (KNN) was applied to classify the monogenean specimens based on the extracted features. 50% of the dataset was used for training and the other 50% was used as testing for system evaluation. Our approach demonstrated overall classification accuracy of 90%. In this study Leave One Out (LOO) cross validation is used for validation of our system and the accuracy is 91.25%. The methods presented in this study facilitate fast and accurate fully automated classification of monogeneans at the species level. In future studies more classes will be included in the model, the time to capture the monogenean images will be reduced and improvements in

  9. A new and practical method to obtain grain size measurements in sandy shores based on digital image acquisition and processing

    NASA Astrophysics Data System (ADS)

    Baptista, P.; Cunha, T. R.; Gama, C.; Bernardes, C.

    2012-12-01

    Modern methods for the automated evaluation of sediment size in sandy shores relay on digital image processing algorithms as an alternative to time-consuming traditional sieving methodologies. However, the requirements necessary to guarantee that the considered image processing algorithm has a good grain identification success rate impose the need for dedicated hardware setups to capture the sand surface images. Examples are specially designed camera housings that maintain a constant distance between the camera lens and the sand surface, tripods to fix and maintain the camera angle orthogonal to the sand surface, external illumination systems that guarantee the light level necessary for the image processing algorithms, and special lenses and focusing systems for close proximity image capturing. In some cases, controlled image-capturing conditions can make the fieldwork more laborious which incurs in significant costs for monitoring campaigns considering large areas. To circumvent this problem, it is proposed a new automated image-processing algorithm that identifies sand grains in digital images acquired with a standard digital camera without any extra hardware attached to it. The accuracy and robustness of the proposed algorithm are evaluated in this work by means of a laboratory test on previously controlled grain samples, field tests where 64 samples (spread over a beach stretch of 65 km and with grain size ranging from 0.5 mm to 1.9 mm) were processed by both the proposed method and by sieving and finally by manual point count on all acquired images. The calculated root-mean-square (RMS) error between mean grain sizes obtained from the proposed image processing method and the sieve method (for the 64 samples) was 0.33 mm, and for the image processing method versus manual point counts comparison, with the same images, was 0.12 mm. The achieved correlation coefficients (r) were 0.91 and 0.96, respectively.

  10. Digital image processing of Seabeam bathymetric data for structural studies of seamounts near the East Pacific Rise

    NASA Technical Reports Server (NTRS)

    Edwards, M. H.; Arvidson, R. E.; Guinness, E. A.

    1984-01-01

    The problem of displaying information on the seafloor morphology is attacked by utilizing digital image processing techniques to generate images for Seabeam data covering three young seamounts on the eastern flank of the East Pacific Rise. Errors in locations between crossing tracks are corrected by interactively identifying features and translating tracks relative to a control track. Spatial interpolation techniques using moving averages are used to interpolate between gridded depth values to produce images in shaded relief and color-coded forms. The digitally processed images clarify the structural control on seamount growth and clearly show the lateral extent of volcanic materials, including the distribution and fault control of subsidiary volcanic constructional features. The image presentations also clearly show artifacts related to both residual navigational errors and to depth or location differences that depend on ship heading relative to slope orientation in regions with steep slopes.

  11. Conference on Applications of Digital Image Processing to Astronomy, Pasadena, Calif., August 20-22, 1980, Proceedings

    NASA Technical Reports Server (NTRS)

    Elliott, D. A.

    1980-01-01

    The astronomic applications of non-military digital image processing are covered in this conference volume. Systems like CCD's, interactive data analysis facilities, stellar speckle interferometry, sky flux subsystems, guide star systems and various image processing systems are described. Techniques in photometry including filtering, automatic photometry, and image restoration are examined. Digital spectral analyses of galaxies, supernova remnants, stars and other celestial bodies are discussed together with algorithms developed to calibrate, clean up, enhance, and quantitatively analyze data. The techniques of image processing permit astronomers to make much more efficient use of their data for both subjective and quantitative analyses. Future missions, such as the Space Telescope, representing a vast data base are briefly covered.

  12. Conference on Applications of Digital Image Processing to Astronomy, Pasadena, Calif., August 20-22, 1980, Proceedings

    NASA Technical Reports Server (NTRS)

    Elliott, D. A.

    1980-01-01

    The astronomic applications of non-military digital image processing are covered in this conference volume. Systems like CCD's, interactive data analysis facilities, stellar speckle interferometry, sky flux subsystems, guide star systems and various image processing systems are described. Techniques in photometry including filtering, automatic photometry, and image restoration are examined. Digital spectral analyses of galaxies, supernova remnants, stars and other celestial bodies are discussed together with algorithms developed to calibrate, clean up, enhance, and quantitatively analyze data. The techniques of image processing permit astronomers to make much more efficient use of their data for both subjective and quantitative analyses. Future missions, such as the Space Telescope, representing a vast data base are briefly covered.

  13. Determination of representative elementary areas for soil redoximorphic features by digital image processing

    USDA-ARS?s Scientific Manuscript database

    Photography has been a welcome tool in documenting and conveying qualitative soil information. When coupled with image analysis software, the usefulness of digital cameras can be increased to advance the field of micropedology. The determination of a Representative Elementary Area (REA) still rema...

  14. Integration of clinical routine digital imaging and advanced image processing through PACS

    NASA Astrophysics Data System (ADS)

    ter Haar Romeny, Bart M.; Viergever, Max A.; van Waes, P. F. G. M.; Zonneveld, F. W.; de Graaf, C. N.; Wilmink, J. B.; Kouwenberg, Jef M.; Neeleman, L.

    1990-08-01

    The University Hospital Utrecht (UHU) has been the site for clinical evaluation of a prototype Picture Archiving and Communication System (PACS), as a part of the Dutch PACS project run by BAZIS, Phffips Medical Systems and the UHU in the period 19864989 k The 800 bed UHU moved in July 1989 to a new campus site facifity (Figure 1.). This offered the opportunity to design the new radiology department to be prepared for a future large scale PACS. The set-up includes an ergonomically designed digital reading room, a centrally located computer room, cooling and cabling, a video network covering the total department and facilities for teleradiology. Radiology, Radiotherapy and Nuclear Medicine are organized in one department.

  15. Fast processing of digital imaging and communications in medicine (DICOM) metadata using multiseries DICOM format.

    PubMed

    Ismail, Mahmoud; Philbin, James

    2015-04-01

    The digital imaging and communications in medicine (DICOM) information model combines pixel data and its metadata in a single object. There are user scenarios that only need metadata manipulation, such as deidentification and study migration. Most picture archiving and communication system use a database to store and update the metadata rather than updating the raw DICOM files themselves. The multiseries DICOM (MSD) format separates metadata from pixel data and eliminates duplicate attributes. This work promotes storing DICOM studies in MSD format to reduce the metadata processing time. A set of experiments are performed that update the metadata of a set of DICOM studies for deidentification and migration. The studies are stored in both the traditional single frame DICOM (SFD) format and the MSD format. The results show that it is faster to update studies' metadata in MSD format than in SFD format because the bulk data is separated in MSD and is not retrieved from the storage system. In addition, it is space efficient to store the deidentified studies in MSD format as it shares the same bulk data object with the original study. In summary, separation of metadata from pixel data using the MSD format provides fast metadata access and speeds up applications that process only the metadata.

  16. Fast processing of digital imaging and communications in medicine (DICOM) metadata using multiseries DICOM format

    PubMed Central

    Ismail, Mahmoud; Philbin, James

    2015-01-01

    Abstract. The digital imaging and communications in medicine (DICOM) information model combines pixel data and its metadata in a single object. There are user scenarios that only need metadata manipulation, such as deidentification and study migration. Most picture archiving and communication system use a database to store and update the metadata rather than updating the raw DICOM files themselves. The multiseries DICOM (MSD) format separates metadata from pixel data and eliminates duplicate attributes. This work promotes storing DICOM studies in MSD format to reduce the metadata processing time. A set of experiments are performed that update the metadata of a set of DICOM studies for deidentification and migration. The studies are stored in both the traditional single frame DICOM (SFD) format and the MSD format. The results show that it is faster to update studies’ metadata in MSD format than in SFD format because the bulk data is separated in MSD and is not retrieved from the storage system. In addition, it is space efficient to store the deidentified studies in MSD format as it shares the same bulk data object with the original study. In summary, separation of metadata from pixel data using the MSD format provides fast metadata access and speeds up applications that process only the metadata. PMID:26158117

  17. Three-dimensional measurement of turbulent shear flows using digital image processing

    NASA Astrophysics Data System (ADS)

    Kasagi, Nobuhide; Nishino, Koichi

    1991-12-01

    A three Dimensional Particle Tracking Velocimeter (3-D PTV) for the measurement of turbulent shear flows is described with emphasis on its instrumentation, experimental procedure and data processing algorithm. Motions of neutrally buoyant tracer particles (Nylon 12, specific density of 1.02, typical diameter of 200 micrometer) suspended in a water flow are tracked with a highly automated digital image processing system. Local fluid velocities are determined from 3-D displacement of each particle and the time interval over which particles are tracked. This technique is advantageous over existing one point measuring techniques such as hot-wire and film probes and a laser Doppler velocimeter in that it can provide not only one point turbulence statistics but also spatial information on the turbulence structures. Such a feature is particularly desirable for the study of coherent turbulence structures which are considered to play a dominant roll in turbulence mechanism. Typical results obtained by the 3-D PTV in fundamental turbulent flows are presented to demonstrate practical capability of the technique. Some perspectives on future research direction of the 3-D PTV are also presented.

  18. Estimation of reactive surface area using a combined method of laboratory analyses and digital image processing

    NASA Astrophysics Data System (ADS)

    Ma, Jin; Kong, Xiang-Zhao; Saar, Martin O.

    2017-04-01

    Fluid-rock interactions play an important role in the engineering processes such as chemical stimulation of enhanced geothermal systems and carbon capture, utilization, and storage. However, these interactions highly depend on the accessible reactive surface area of the minerals that are generally poorly constrained for natural geologic samples. In particular, quantifying surface area of each reacting mineral within whole rock samples is challenging due to the heterogeneous distribution of minerals and pore space. In this study, detailed laboratory analyses were performed on sandstone samples from deep geothermal sites in Lithuania. We measure specific surface area of whole rock samples using a gas adsorption method (so-called B.E.T.) with N2 at a temperature of 77.3K. We also quantify their porosity and pore size distribution by a Helium gas pycnometer and a Hg porosimetry, respectively. Rock compositions are determined by a combination of X-ray fluorescence (XRF) and quantitative scanning electron microscopy (SEM) - Energy-dispersive X-ray spectroscopy (EDS), which are later geometrically mapped on images of two-dimensional SEM- Backscattered electrons (BSE) with a resolution of 1.2 μm and three-dimensional micro-CT with a resolution of 10.3 μm to produce a digital mineral map for further constraining the accessibility of reactive minerals. Moreover, we attempt to link the whole rock porosity, pore size distribution, and B.E.T. specific surface area with the digital mineral maps. We anticipate these necessary analyses to provide in-depth understanding of fluid sample chemistry from later hydrothermal reactive flow-through experiments on whole rock samples at elevated pressure and temperature.

  19. Digital image storage.

    PubMed

    Wallack, Seth

    2008-01-01

    Digital image archival requires less physical storage space, allows for rapid storage and retrieval and avoids loss in image quality over time or with image duplication compared with film storage. Because medical imaging data are critically important and, by law, must be stored in a safe, accessible manner, it is imperative not to have one computer error destroy all copies of the image data. Several options for image storage media are available including magnetic tape, optical media, spinning disks and solid state. Other considerations include on-site vs. off-site storage, redundancy, on-line vs. off-line storage, and removable storage media for disaster recovery. The different storage media can be used in different configurations to provide sufficient protection of digital data. Choose a storage system that will keep your data safe from unauthorized access, hardware failure, and clinic disasters.

  20. Digital X-Ray Imaging

    NASA Astrophysics Data System (ADS)

    Dance, David R.

    The use of X-ray image receptors that produce a digital image is becoming increasingly important. Possible benefits include improved dynamic range and detective quantum efficiency, improved detectability for objects of low intrinsic contrast, and reduced radiation dose. The image can be available quickly. The display is separated from the image capture so that processing and contrast adjustment are possible before the image is viewed. The availability of a digital image means ready input into PACS and opens up the possibility of computer-aided detection and classification of abnormality. Possible drawbacks of digital systems include high cost, limited high contrast resolution and the fact that their clinical value is sometimes not proven in comparison with conventional, analogue techniques. The high contrast resolution attainable with such systems is discussed and the problem of sampling limitations and aliasing considered. The properties and limitations of digital systems using computed radiography, caesium iodide plus CCDs and active matrix arrays with either caesium iodide or selenium detectors are demonstrated. Examples are given of digital systems for mammography and general radiography and their performance is demonstrated in terms of clinical assessment and measurements of the modulation transfer function and detective quantum efficiency.

  1. Fractal and digital image processing to determine the degree of dispersion of carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Liang, Xiao-ning; Li, Wei

    2016-05-01

    The degree of dispersion is an important parameter to quantitatively study properties of carbon nanotube composites. Among the many methods for studying dispersion, scanning electron microscopy, transmission electron microscopy, and atomic force microscopy are the most commonly used, intuitive, and convincing methods. However, they have the disadvantage of not being quantitative. To overcome this disadvantage, the fractal theory and digital image processing method can be used to provide a quantitative analysis of the morphology and properties of carbon nanotube composites. In this paper, the dispersion degree of carbon nanotubes was investigated using two fractal methods, namely, the box-counting method and the differential box-counting method. On the basis of the results, we propose a new method for the quantitative characterization of the degree of dispersion of carbon nanotubes. This hierarchical grid method can be used as a supplementary method, and can be combined with the fractal calculation method. Thus, the accuracy and effectiveness of the quantitative characterization of the dispersion degree of carbon nanotubes can be improved. (The outer diameter of the carbon nanotubes is about 50 nm; the length of the carbon nanotubes is 10-20 μm.)

  2. Digitization and image processing methods for enhancement and quantification of grazing-incidence x-ray topographs.

    PubMed

    Rheinländer, J; Abdali, S; Zielinska-Rohozinska, E

    1994-01-01

    The conventional photographic prints obtained from double crystal x-ray topography are often hard to interprete and reproduce. Photographic enhancement methods require skillful work by an experienced photographer. They are time consuming and the image information is difficult to present quantitatively. Alternatively, image processing methods may be applied by digitization of the original topographic recording. Image processing computer programs may be applied, e.g., for image enhancement and for quantification of image information. This paper's main interest is related to-obtaining a sufficiently high magnification ratio;-correcting for intensity variations within the image;-applying spatial filtering techniques in order to reduce film grain noise;-improving contrast, and-retrieving quantative information on image details.The application of such image processing routines is exemplified on topographs obtained by a double-crystal diffractometer set to the (+, -) asymmetric-asymmetric setting. A silicon single crystal was used as the monochromator, while the sample was a silicon single crystal which had undergone both surface damage and metallic contamination before the application of Rapid Thermal Annealing (RTA). Hence, well-defined microdefects are found within the sample. These computer-processed images are compared with corresponding images enhanced by conventional techniques. The results provide indications of which enhancement procedures should be applied for qualitative image improvement and for quantification of image details within different types of topographic recordings.

  3. Analysis of ROC on chest direct digital radiography (DR) after image processing in diagnosis of SARS

    NASA Astrophysics Data System (ADS)

    Lv, Guozheng; Lan, Rihui; Zeng, Qingsi; Zheng, Zhong

    2004-05-01

    The Severe Acute Respiratory Syndrome (SARS, also called Infectious Atypical Pneumonia), which initially broke out in late 2002, has threatened the public"s health seriously. How to confirm the patients contracting SARS becomes an urgent issue in diagnosis. This paper intends to evaluate the importance of Image Processing in the diagnosis on SARS at the early stage. Receiver Operating Characteristics (ROC) analysis has been employed in this study to compare the value of DR images in the diagnosis of SARS patients before and after image processing by Symphony Software supplied by E-Com Technology Ltd., and DR image study of 72 confirmed or suspected SARS patients were reviewed respectively. All the images taken from the studied patients were processed by Symphony. Both the original and processed images were taken into ROC analysis, based on which the ROC graph for each group of images has been produced as described below: For processed images: a = 1.9745, b = 1.4275, SA = 0.8714; For original images: a = 0.9066, b = 0.8310, SA = 0.7572; (a - intercept, b - slop, SA - Area below the curve). The result shows significant difference between the original images and processed images (P<0.01). In summary, the images processed by Symphony are superior to the original ones in detecting the opacity lesion, and increases the accuracy of SARS diagnosis.

  4. Artifacts in digital images

    NASA Technical Reports Server (NTRS)

    Lorre, J. J.; Gillespie, A. R.

    1980-01-01

    Three kinds of artifacts unique to digital images are illustrated, namely aliasing caused by undersampling, interference phenomena caused by improper display of images, and harmonic overtones caused by quantization of amplitudes. Special attention is given to undersampling when the sample size and interval are the same. It is noted that this situation is important because it is typical of solid-state cameras. Quantization of image data of necessity introduces energy at harmonic overtones of the image spectrum. This energy is aliased if the frequency of the overtones is greater than 0.5 cycle/pixel. It cannot be selectively removed from the image through filtering, and the best way to suppress it is to maximize the amplification of the sensor before digital encoding.

  5. Digital Image Correlation Engine

    SciTech Connect

    Turner, Dan; Crozier, Paul; Reu, Phil

    2015-10-06

    DICe is an open source digital image correlation (DIC) tool intended for use as a module in an external application or as a standalone analysis code. It's primary capability is computing full –field displacements and strains from sequences of digital These images are typically of a material sample undergoing a materials characterization experiment, but DICe is also useful for other applications (for example, trajectory tracking). DICe is machine portable (Windows, Linux and Mac) and can be effectively deployed on a high performance computing platform. Capabilities from DICe can be invoked through a library interface, via source code integration of DICe classes or through a graphical user interface.

  6. Methods in Astronomical Image Processing

    NASA Astrophysics Data System (ADS)

    Jörsäter, S.

    A Brief Introductory Note History of Astronomical Imaging Astronomical Image Data Images in Various Formats Digitized Image Data Digital Image Data Philosophy of Astronomical Image Processing Properties of Digital Astronomical Images Human Image Processing Astronomical vs. Computer Science Image Processing Basic Tools of Astronomical Image Processing Display Applications Calibration of Intensity Scales Calibration of Length Scales Image Re-shaping Feature Enhancement Noise Suppression Noise and Error Analysis Image Processing Packages: Design of AIPS and MIDAS AIPS MIDAS Reduction of CCD Data Bias Subtraction Clipping Preflash Subtraction Dark Subtraction Flat Fielding Sky Subtraction Extinction Correction Deconvolution Methods Rebinning/Combining Summary and Prospects for the Future

  7. Manual on characteristics of Landsat computer-compatible tapes produced by the EROS Data Center digital image processing system

    USGS Publications Warehouse

    Holkenbrink, Patrick F.

    1978-01-01

    Landsat data are received by National Aeronautics and Space Administration (NASA) tracking stations and converted into digital form on high-density tapes (HDTs) by the Image Processing Facility (IPF) at the Goddard Space Flight Center (GSFC), Greenbelt, Maryland. The HDTs are shipped to the EROS Data Center (EDC) where they are converted into customer products by the EROS Data Center digital image processing system (EDIPS). This document describes in detail one of these products: the computer-compatible tape (CCT) produced from Landsat-1, -2, and -3 multispectral scanner (MSS) data and Landsat-3 only return-beam vidicon (RBV) data. Landsat-1 and -2 RBV data will not be processed by IPF/EDIPS to CCT format.

  8. Linear densitometry and digital image processing of proximal femur radiographs: implications for archaeological and forensic anthropology.

    PubMed

    Macchiarelli, R; Bondioli, L

    1994-01-01

    Age- and sex-related patterns of proximal femur trabecular bone loss have previously been used to establish radiographic reference standards for estimating age at death for human skeletal remains. Such standards are of interest to both anthropologists and forensic scientists. However, osteopenia as a physiological phenomenon is dependent on numerous genetic, environmental, and cultural factors. Thus, while general age- and sex-related trends can be clearly observed for trabecular bone loss, such patterns also demonstrate marked variation among individuals of both sexes at all ages. Moreover, clinical evidence shows that rates of bone loss are not steady but episodic, and that radiographically "normal" (i.e., young adult) patterns of trabecular bone architecture can also exist in femora of older individuals, particularly within samples of African origin. In this study, adult proximal femur radiographs were used to explore patterns of age- and sex-related proximal femur cancellous bone involution among a sample of 66 African-American individuals from the Terry collection (33 males and 33 females), ranging in age from 19 to 71 years. The proximal femur radiographs of these subjects were analyzed by digital image processing (DIP), and the results were compared to those obtained by laser linear densitometric analyses (LDA) previously performed on the same series (Macchiarelli et al., 1987). Results of LDA and DIP analyses indicate (a) more pronounced bone density decrease in females; (b) sex- and site-specific structural patterns of proximal femur trabecular bone loss; (c) a high level of individual variability, in which predicted age deviated from real age by as much as 22.26 (males) and 30.78 years (females); (d) a moderate linear correlation with age for all the variables analyzed; and (e) an average discrepancy between known age and predicted age (measured by root mean squared residual values) of 10.34 (males) and 12.71 years (females) for the most satisfactory DIP

  9. Light microscopy digital imaging.

    PubMed

    Joubert, James; Sharma, Deepak

    2011-10-01

    This unit presents an overview of digital imaging hardware used in light microscopy. CMOS, CCD, and EMCCDs are the primary sensors used. The strengths and weaknesses of each define the primary applications for these sensors. Sensor architecture and formats are also reviewed. Color camera design strategies and sensor window cleaning are also described in the unit.

  10. Digital Images and Human Vision

    NASA Technical Reports Server (NTRS)

    Watson, Andrew B.; Null, Cynthia H. (Technical Monitor)

    1997-01-01

    Processing of digital images destined for visual consumption raises many interesting questions regarding human visual sensitivity. This talk will survey some of these questions, including some that have been answered and some that have not. There will be an emphasis upon visual masking, and a distinction will be drawn between masking due to contrast gain control processes, and due to processes such as hypothesis testing, pattern recognition, and visual search.

  11. [Image processing system of visual prostheses based on digital signal processor DM642].

    PubMed

    Xie, Chengcheng; Lu, Yanyu; Gu, Yun; Wang, Jing; Chai, Xinyu

    2011-09-01

    This paper employed a DSP platform to create the real-time and portable image processing system, and introduced a series of commonly used algorithms for visual prostheses. The results of performance evaluation revealed that this platform could afford image processing algorithms to be executed in real time.

  12. Digital image transformation and rectification of spacecraft and radar images

    USGS Publications Warehouse

    Wu, S.S.C.

    1985-01-01

    Digital image transformation and rectification can be described in three categories: (1) digital rectification of spacecraft pictures on workable stereoplotters; (2) digital correction of radar image geometry; and (3) digital reconstruction of shaded relief maps and perspective views including stereograms. Digital rectification can make high-oblique pictures workable on stereoplotters that would otherwise not accommodate such extreme tilt angles. It also enables panoramic line-scan geometry to be used to compile contour maps with photogrammetric plotters. Rectifications were digitally processed on both Viking Orbiter and Lander pictures of Mars as well as radar images taken by various radar systems. By merging digital terrain data with image data, perspective and three-dimensional views of Olympus Mons and Tithonium Chasma, also of Mars, are reconstructed through digital image processing. ?? 1985.

  13. A novel digital image processing system for the transient liquid crystal technique applied for heat transfer and film cooling measurements.

    PubMed

    Vogel, G; Boelcs, A

    2001-05-01

    This paper is dedicated to the transient liquid crystal technique measurements for multiple view access by using a novel digital recording and image processing system. The transient liquid crystal technique is widely used for heat transfer investigations in turbomachinery. It has been applied in our laboratory in several test facilities such as a linear cascade for external film cooling measurements or on a ribbed squared duct for internal cooling measurements. The data analysis as well as the measurement equipment is described, with a special focus on the newly developed computerized image processing system suitable to capture the liquid crystal signal.

  14. [Evaluation of bone mineral density using digital image processing in children receiving anticonvulsants].

    PubMed

    Suzuki, Keiko; Ueda, Satoru; Umezu, Ryouji; Matsuoka, Hisafumi; Sugihara, Shigetaka

    2007-09-01

    Bone mineral density (BMD) increases rapidly in a biphasic manner in childhood. During and after adolescence, BMD correlates more closely with bone age than chronological age. Digital image processing (DIP) allows the rapid assessment of BMD and bone age on one X-ray film. Herein, using DIP methods, the effects of various anticonvulsants on chronological and bone age were evaluated in 98 epilepsy patients (age range, 3-15 years) with no intellectual or motor disorders or diseases affecting bone metabolism. All patients were taking one or a combination of the following anticonvulsants: valproate sodium (VPA); carbamazepine (CBZ); and phenobarbital (PB). Bone maturation scores for radius-ulnar-short bones (RUS) were calculated using Tanner-Whitehouse 2 methods. Bone age was determined based on standard Japanese bone-maturation scores. In each patient, Z-scores for chronological and bone ages were calculated by subtracting standard BMD for gender and age from each BMD, then dividing the result by the standard deviation. The Z-score for each drug in relation to the administration period was analyzed using the Mann-Whitney test. For chronological age, significant differences in BMD were observed regarding the administration periods in children taking multiple drugs, but not in children on VPA, CBZ, or PB monotherapy. For bone age, no significant differences in BMD were observed regarding the administration periods for all drugs. Children taking multiple drugs showed a significant negative correlation between administration period and Z-scores for BMD calculated based on chronological age (Spearman rank correlation: - 0.457, p = 0.008), but not bone age. Among children receiving long-term VPA administration, bone age was delayed approximately 1 year, and bone maturation may have been delayed. No delay in bone age was noted among children receiving long-term administration of multiple drugs, suggesting that these anticonvulsants do not influence bone maturity. These

  15. Lipase Production in Solid-State Fermentation Monitoring Biomass Growth of Aspergillus niger Using Digital Image Processing

    NASA Astrophysics Data System (ADS)

    Dutra, Julio C. V.; da Terzi, Selma C.; Bevilaqua, Juliana Vaz; Damaso, Mônica C. T.; Couri, Sônia; Langone, Marta A. P.; Senna, Lilian F.

    The aim of this study was to monitor the biomass growth of Aspergillus niger in solid-state fermentation (SSF) for lipase production using digital image processing technique. The strain A. niger 11T53A14 was cultivated in SSF using wheat bran as support, which was enriched with 0.91% (m/v) of ammonium sulfate. The addition of several vegetable oils (castor, soybean, olive, corn, and palm oils) was investigated to enhance lipase production. The maximum lipase activity was obtained using 2% (m/m) castor oil. In these conditions, the growth was evaluated each 24 h for 5 days by the glycosamine content analysis and digital image processing. Lipase activity was also determined. The results indicated that the digital image process technique can be used to monitor biomass growth in a SSF process and to correlate biomass growth and enzyme activity. In addition, the immobilized esterification lipase activity was determined for the butyl oleate synthesis, with and without 50% v/v hexane, resulting in 650 and 120 U/g, respectively. The enzyme was also used for transesterification of soybean oil and ethanol with maximum yield of 2.4%, after 30 min of reaction.

  16. Individual sarcomere length determination from isolated cardiac cells using high-resolution optical microscopy and digital image processing.

    PubMed Central

    Roos, K P; Brady, A J

    1982-01-01

    Discrete sarcomere lengths have been determined from dynamically contracting isolated cardiac cells with a high-speed, high-resolution direct optical imaging system. Calcium-tolerant cardiac cells from the rat are isolated by perfusion with collagenase and hyaluronidase. Individual sarcomere lengths can be determined by directly imaging the cell's striation pattern onto a solid-state charge-coupled device (CCD) detector interfaced with a digital computer. The precision of detection in a real light microscopic optical system is discussed in relation to the type of image detector, optical contract enhancement techniques, and digital image processing. The optical performance of the direct striation pattern image apparatus has been determined empirically with test grids under standard bright-field and Nomarski-differential interference contrast (DIC) conditions for application to real muscle imaging. Discrete striation positions of isolated cells have been detected and followed with high precision during phasic contraction-relaxation cycles down to average sarcomere lengths as short as 1.43 +/- 0.053 microns. The maximum rates of contraction and relaxation are rapid and synchronous in time course along the length of the cell. These results indicate that direct optical imaging can provide an accurate means to monitor discrete striations and sarcomere lengths along the length of Ca2+-tolerant heart cells. Images FIGURE 1 FIGURE 4 PMID:7183337

  17. Comparison of manually produced and automated cross country movement maps using digital image processing techniques

    NASA Technical Reports Server (NTRS)

    Wynn, L. K.

    1985-01-01

    The Image-Based Information System (IBIS) was used to automate the cross country movement (CCM) mapping model developed by the Defense Mapping Agency (DMA). Existing terrain factor overlays and a CCM map, produced by DMA for the Fort Lewis, Washington area, were digitized and reformatted into geometrically registered images. Terrain factor data from Slope, Soils, and Vegetation overlays were entered into IBIS, and were then combined utilizing IBIS-programmed equations to implement the DMA CCM model. The resulting IBIS-generated CCM map was then compared with the digitized manually produced map to test similarity. The numbers of pixels comprising each CCM region were compared between the two map images, and percent agreement between each two regional counts was computed. The mean percent agreement equalled 86.21%, with an areally weighted standard deviation of 11.11%. Calculation of Pearson's correlation coefficient yielded +9.997. In some cases, the IBIS-calculated map code differed from the DMA codes: analysis revealed that IBIS had calculated the codes correctly. These highly positive results demonstrate the power and accuracy of IBIS in automating models which synthesize a variety of thematic geographic data.

  18. Image Processing Software

    NASA Astrophysics Data System (ADS)

    Bosio, M. A.

    1990-11-01

    ABSTRACT: A brief description of astronomical image software is presented. This software was developed in a Digital Micro Vax II Computer System. : St presenta una somera descripci6n del software para procesamiento de imagenes. Este software fue desarrollado en un equipo Digital Micro Vax II. : DATA ANALYSIS - IMAGE PROCESSING

  19. Reproducibility of immunostaining quantification and description of a new digital image processing procedure for quantitative evaluation of immunohistochemistry in pathology.

    PubMed

    Bernardo, Vagner; Lourenço, Simone Q C; Cruz, Renato; Monteiro-Leal, Luiz H; Silva, Licínio E; Camisasca, Danielle R; Farina, Marcos; Lins, Ulysses

    2009-08-01

    Quantification of immunostaining is a widely used technique in pathology. Nonetheless, techniques that rely on human vision are prone to inter- and intraobserver variability, and they are tedious and time consuming. Digital image analysis (DIA), now available in a variety of platforms, improves quantification performance: however, the stability of these different DIA systems is largely unknown. Here, we describe a method to measure the reproducibility of DIA systems. In addition, we describe a new image-processing strategy for quantitative evaluation of immunostained tissue sections using DAB/hematoxylin-stained slides. This approach is based on image subtraction, using a blue low pass filter in the optical train, followed by digital contrast and brightness enhancement. Results showed that our DIA system yields stable counts, and that this method can be used to evaluate the performance of DIA systems. The new image-processing approach creates an image that aids both human visual observation and DIA systems in assessing immunostained slides, delivers a quantitative performance similar to that of bright field imaging, gives thresholds with smaller ranges, and allows the segmentation of strongly immunostained areas, all resulting in a higher probability of representing specific staining. We believe that our approach offers important advantages to immunostaining quantification in pathology.

  20. Digital imaging in dentistry.

    PubMed

    Essen, S Donovan

    2011-01-01

    Information technology is vital to operations, marketing, accounting, finance and administration. One of the most exciting and quickly evolving technologies in the modern dental office is digital applications. The dentist is often the business manager, information technology officer and strategic planning chief for his small business. The information systems triangle applies directly to this critical manager supported by properly trained ancillary staff and good equipment. With emerging technology driving all medical disciplines and the rapid pace at which it emerges, it is vital for the contemporary practitioner to keep abreast of the newest information technology developments. This article compares the strategic and operational advantages of digital applications, specifically imaging. The focus of this paper will be on digital radiography (DR), 3D computerized tomography, digital photography and digitally-driven CAD/CAM to what are now considered obsolescing modalities and contemplates what may arrive in the future. It is the purpose of this essay to succinctly evaluate the decisions involved in the role, application and implications of employing this tool in the dental environment

  1. Automatic classification of atypical lymphoid B cells using digital blood image processing.

    PubMed

    Alférez, S; Merino, A; Mujica, L E; Ruiz, M; Bigorra, L; Rodellar, J

    2014-08-01

    There are automated systems for digital peripheral blood (PB) cell analysis, but they operate most effectively in nonpathological blood samples. The objective of this work was to design a methodology to improve the automatic classification of abnormal lymphoid cells. We analyzed 340 digital images of individual lymphoid cells from PB films obtained in the CellaVision DM96:150 chronic lymphocytic leukemia (CLL) cells, 100 hairy cell leukemia (HCL) cells, and 90 normal lymphocytes (N). We implemented the Watershed Transformation to segment the nucleus, the cytoplasm, and the peripheral cell region. We extracted 44 features and then the clustering Fuzzy C-Means (FCM) was applied in two steps for the lymphocyte classification. The images were automatically clustered in three groups, one of them with 98% of the HCL cells. The set of the remaining cells was clustered again using FCM and texture features. The two new groups contained 83.3% of the N cells and 71.3% of the CLL cells, respectively. The approach has been able to automatically classify with high precision three types of lymphoid cells. The addition of more descriptors and other classification techniques will allow extending the classification to other classes of atypical lymphoid cells. © 2013 John Wiley & Sons Ltd.

  2. Apple Image Processing Educator

    NASA Technical Reports Server (NTRS)

    Gunther, F. J.

    1981-01-01

    A software system design is proposed and demonstrated with pilot-project software. The system permits the Apple II microcomputer to be used for personalized computer-assisted instruction in the digital image processing of LANDSAT images. The programs provide data input, menu selection, graphic and hard-copy displays, and both general and detailed instructions. The pilot-project results are considered to be successful indicators of the capabilities and limits of microcomputers for digital image processing education.

  3. Apple Image Processing Educator

    NASA Technical Reports Server (NTRS)

    Gunther, F. J.

    1981-01-01

    A software system design is proposed and demonstrated with pilot-project software. The system permits the Apple II microcomputer to be used for personalized computer-assisted instruction in the digital image processing of LANDSAT images. The programs provide data input, menu selection, graphic and hard-copy displays, and both general and detailed instructions. The pilot-project results are considered to be successful indicators of the capabilities and limits of microcomputers for digital image processing education.

  4. Low-cost digital image processing on a university mainframe computer. [considerations in selecting and/or designing instructional systems

    NASA Technical Reports Server (NTRS)

    Williams, T. H. L.

    1981-01-01

    The advantages and limitations of using university mainframe computers in digital image processing instruction are listed. Aspects to be considered when designing software for this purpose include not only two general audience, but also the capabilities of the system regarding the size of the image/subimage, preprocessing and enhancement functions, geometric correction and registration techniques; classification strategy, classification algorithm, multitemporal analysis, and ancilliary data and geographic information systems. The user/software/hardware interaction as well as acquisition and operating costs must also be considered.

  5. Digital image processing versus visual assessment of chewed two-colour wax in mixing ability tests.

    PubMed

    van der Bilt, A; Speksnijder, C M; de Liz Pocztaruk, R; Abbink, J H

    2012-01-01

    Two-colour chewing gum and wax have been widely used as test foods to evaluate the ability to mix and knead a food bolus. The mixing of the colours has been assessed by computer analysis or by visual inspection. Reports contradict each other about whether computer analysis and visual assessment could equally well discriminate between the masticatory performances of groups of participants with different dental status. This study compares the results of computer analysis of digital images of chewed two-colour wax with the results of visual assessment of these images. Sixty healthy subjects participated and chewed on red-blue wax for 5, 10, 15 and 20 chewing strokes. The subjects were divided into three groups of 20, matched for age and gender, according to their dental status: natural dentition, full dentures and maxillary denture plus implant-supported mandibular overdenture. Mixing of the chewed wax was determined by computer analysis of images of the wax and by visual assessment of the images by five examiners. Both the computer method and the observers were able to distinguish the mixing abilities of the dentate subjects from the two denture wearer groups. Computer analysis could also discriminate the mixing abilities of the two denture groups. However, observers were not able to distinguish the mixing abilities of the two denture groups after 5, 10 and 15 chewing strokes. Only after 20 chewing strokes, they could detect a significant difference in mixing ability.

  6. apART: system for the acquisition, processing, archiving, and retrieval of digital images in an open, distributed imaging environment

    NASA Astrophysics Data System (ADS)

    Schneider, Uwe; Strack, Ruediger

    1992-04-01

    apART reflects the structure of an open, distributed environment. According to the general trend in the area of imaging, network-capable, general purpose workstations with capabilities of open system image communication and image input are used. Several heterogeneous components like CCD cameras, slide scanners, and image archives can be accessed. The system is driven by an object-oriented user interface where devices (image sources and destinations), operators (derived from a commercial image processing library), and images (of different data types) are managed and presented uniformly to the user. Browsing mechanisms are used to traverse devices, operators, and images. An audit trail mechanism is offered to record interactive operations on low-resolution image derivatives. These operations are processed off-line on the original image. Thus, the processing of extremely high-resolution raster images is possible, and the performance of resolution dependent operations is enhanced significantly during interaction. An object-oriented database system (APRIL), which can be browsed, is integrated into the system. Attribute retrieval is supported by the user interface. Other essential features of the system include: implementation on top of the X Window System (X11R4) and the OSF/Motif widget set; a SUN4 general purpose workstation, inclusive ethernet, magneto optical disc, etc., as the hardware platform for the user interface; complete graphical-interactive parametrization of all operators; support of different image interchange formats (GIF, TIFF, IIF, etc.); consideration of current IPI standard activities within ISO/IEC for further refinement and extensions.

  7. Automatic identification of human helminth eggs on microscopic fecal specimens using digital image processing and an artificial neural network.

    PubMed

    Yang, Y S; Park, D K; Kim, H C; Choi, M H; Chai, J Y

    2001-06-01

    In order to automate routine fecal examination for parasitic diseases, we propose in this study a computer processing algorithm using digital image processing techniques and an artificial neural network (ANN) classifier. The morphometric characteristics of eggs of human parasites in fecal specimens were extracted from microscopic images through digital image processing. An ANN then identified the parasite species based on those characteristics. We selected four morphometric features based on three morphological characteristics representing shape, shell smoothness, and size. A total of 82 microscopic images containing seven common human helminth eggs were used. The first stage (ANN-1) of the proposed ANN classification system isolated eggs from confusing artifacts. The second stage (ANN-2) classified eggs by species. The performance of ANN was evaluated by the tenfold cross-validation method to obviate the dependency on the selection of training samples. Cross-validation results showed 86.1% average correct classification ratio for ANN-1 and 90.3% for ANN-2 with small variances of 46.0 and 39.0, respectively. The algorithm developed will be an essential part of a completely automated fecal examination system.

  8. Digital Images on the DIME

    NASA Technical Reports Server (NTRS)

    2003-01-01

    With NASA on its side, Positive Systems, Inc., of Whitefish, Montana, is veering away from the industry standards defined for producing and processing remotely sensed images. A top developer of imaging products for geographic information system (GIS) and computer-aided design (CAD) applications, Positive Systems is bucking traditional imaging concepts with a cost-effective and time-saving software tool called Digital Images Made Easy (DIME(trademark)). Like piecing a jigsaw puzzle together, DIME can integrate a series of raw aerial or satellite snapshots into a single, seamless panoramic image, known as a 'mosaic.' The 'mosaicked' images serve as useful backdrops to GIS maps - which typically consist of line drawings called 'vectors' - by allowing users to view a multidimensional map that provides substantially more geographic information.

  9. Processing digital images and calculation of beam emittance (pepper-pot method for the Krion source)

    NASA Astrophysics Data System (ADS)

    Alexandrov, V. S.; Donets, E. E.; Nyukhalova, E. V.; Kaminsky, A. K.; Sedykh, S. N.; Tuzikov, A. V.; Philippov, A. V.

    2016-12-01

    Programs for the pre-processing of photographs of beam images on the mask based on Wolfram Mathematica and Origin software are described. Angles of rotation around the axis and in the vertical plane are taken into account in the generation of the file with image coordinates. Results of the emittance calculation by the Pep_emit program written in Visual Basic using the generated file in the test mode are presented.

  10. Radiation dose reduction in digital radiography using wavelet-based image processing methods

    NASA Astrophysics Data System (ADS)

    Watanabe, Haruyuki; Tsai, Du-Yih; Lee, Yongbum; Matsuyama, Eri; Kojima, Katsuyuki

    2011-03-01

    In this paper, we investigate the effect of the use of wavelet transform for image processing on radiation dose reduction in computed radiography (CR), by measuring various physical characteristics of the wavelet-transformed images. Moreover, we propose a wavelet-based method for offering a possibility to reduce radiation dose while maintaining a clinically acceptable image quality. The proposed method integrates the advantages of a previously proposed technique, i.e., sigmoid-type transfer curve for wavelet coefficient weighting adjustment technique, as well as a wavelet soft-thresholding technique. The former can improve contrast and spatial resolution of CR images, the latter is able to improve the performance of image noise. In the investigation of physical characteristics, modulation transfer function, noise power spectrum, and contrast-to-noise ratio of CR images processed by the proposed method and other different methods were measured and compared. Furthermore, visual evaluation was performed using Scheffe's pair comparison method. Experimental results showed that the proposed method could improve overall image quality as compared to other methods. Our visual evaluation showed that an approximately 40% reduction in exposure dose might be achieved in hip joint radiography by using the proposed method.

  11. Digital imaging overview.

    PubMed

    Carrino, John A

    2003-07-01

    Digital imaging consists of digital acquisition modalities, image, and information management systems. All modalities are available to be purchased as digital acquisition devices. Image management has been the domain for PACSs. PACSs are complex systems designed to transmit, store, and display medical images. They use and rely on many types of different information and display technologies. The initial focus for PACSs has been on solving the engineering issues associated with the transfer of large image data sets and the suitability of softcopy displays for diagnosis particular to the human visual system. For operating within a centralized radiology department, these are largely solved. However, for enterprise wide dissemination and distribution, there are still challenges in the form of expedient transfer syntaxes and image quality, but these are also being effectively addressed. Information management is the domain of the RIS. One of the goals of radiology management should encompass the development of a robust practice environment that emphasizes workflow enhancements with seamless integration of decision support tools. The concept of "person-machine" systems emphasizes taking full advantage of both human and machine capabilities with a capacity to grow and change function. As the computer capabilities increase, more jobs can be relinquished to the machine. The physician can then focus on tasks that require more complex judgment and comprehension. The goal of this human-machine hybrid is to have more power than either of its components alone. This multifaceted role will most likely be embedded in the background having agents query and retrieve context specific information to be presented to the user. As augmenters of human talent, computers can turn data into information and information into knowledge. Medical imaging is a beneficiary of the information technology developments driven by the consumer and business sectors. Although these applications of

  12. Application of image processing techniques for contrast enhancement in dense breast digital mammograms

    NASA Astrophysics Data System (ADS)

    Nunes, Fatima d. L. d. S.; Schiabel, Homero; Benatti, Rodrigo H.

    1999-05-01

    Dense breasts, that usually are characteristic of women less than 40 years old, difficult many times early detection of breast cancer. In this work we present the application of some image processing techniques intended to enhance the contrast in dense breast images, regarding the detection of clustered microcalcifications. The procedure was, firstly, determining in the literature the main techniques used for mammographic images contrast enhancement. The results indicate that, in general: (1) as expected, the overall performance of the CAD scheme for clusters detection decreased when applied exclusively to dense breast images, compared to the application to a set of images without this characteristic; (2) most of the techniques for contrast enhancement used successfully in generic mammography images databases are not able to enhance structures of athirst in databases formed only by dense breasts images, due to the very poor contrast between microcalcifications, for example, and other tissues. These features should stress, therefore, the need of developing a methodology specifically for this type of images in order to provide better conditions to the detection of breast suspicious structures in these group of women.

  13. Virtual Observatory: Plate Content Digitization, Archive Mining and Image Sequence Processing, , COST Action 283, in the Einstein Year of Physics, 2005

    NASA Astrophysics Data System (ADS)

    Murtagh, F.

    2006-04-01

    Linking Virtual Observatory: Plate Content Digitization, Archive Mining and Image Sequence Processing, to important historical events, in particular relating to anniversaries in 2005, we describe its work, which is centered around the axes of signal and information.

  14. Low-cost digital image processing at the University of Oklahoma

    NASA Technical Reports Server (NTRS)

    Harrington, J. A., Jr.

    1981-01-01

    Computer assisted instruction in remote sensing at the University of Oklahoma involves two separate approaches and is dependent upon initial preprocessing of a LANDSAT computer compatible tape using software developed for an IBM 370/158 computer. In-house generated preprocessing algorithms permits students or researchers to select a subset of a LANDSAT scene for subsequent analysis using either general purpose statistical packages or color graphic image processing software developed for Apple II microcomputers. Procedures for preprocessing the data and image analysis using either of the two approaches for low-cost LANDSAT data processing are described.

  15. Image Processing Software

    NASA Technical Reports Server (NTRS)

    1990-01-01

    The Ames digital image velocimetry technology has been incorporated in a commercially available image processing software package that allows motion measurement of images on a PC alone. The software, manufactured by Werner Frei Associates, is IMAGELAB FFT. IMAGELAB FFT is a general purpose image processing system with a variety of other applications, among them image enhancement of fingerprints and use by banks and law enforcement agencies for analysis of videos run during robberies.

  16. Application of LANDSAT data and digital image processing. [Ruhr Valley, Germany

    NASA Technical Reports Server (NTRS)

    Bodechtel, J. (Principal Investigator)

    1978-01-01

    The author has identified the following significant results. Based on LANDSAT 1 and 2 data, applications in the fields of coal mining, lignite exploration, and thematic mapping in geology are demonstrated. The hybrid image processing system, its software, and its utilization for educational purposes is described. A pre-operational European satellite is proposed.

  17. Comparison of visual grading and free-response ROC analyses for assessment of image-processing algorithms in digital mammography.

    PubMed

    Zanca, F; Van Ongeval, C; Claus, F; Jacobs, J; Oyen, R; Bosmans, H

    2012-12-01

    To compare two methods for assessment of image-processing algorithms in digital mammography: free-response receiver operating characteristic (FROC) for the specific task of microcalcification detection and visual grading analysis (VGA). The FROC study was conducted prior to the VGA study reported here. 200 raw data files of low breast density (Breast Imaging-Reporting and Data System I-II) mammograms (Novation DR, Siemens, Germany)-100 of which abnormal-were processed by four image-processing algorithms: Raffaello (IMS, Bologna, Italy), Sigmoid (Sectra, Linköping, Sweden), and OpView v. 2 and v. 1 (Siemens, Erlangen, Germany). Four radiologists assessed the mammograms for the detection of microcalcifications. 8 months after the FROC study, a subset (200) of the 800 images was reinterpreted by the same radiologists, using the VGA methodology in a side-by-side approach. The VGA grading was based on noise, saturation, contrast, sharpness and confidence with the image in terms of normal structures. Ordinal logistic regression was applied; OpView v. 1 was the reference processing algorithm. In the FROC study all algorithms performed better than OpView v. 1. From the current VGA study and for confidence with the image, Sigmoid and Raffaello were significantly worse (p<0.001) than OpView v. 1; OpView v. 2 was significantly better (p=0.01). For the image quality criteria, results were mixed; Raffaello and Sigmoid for example were better than OpView v. 1 for sharpness and contrast (although not always significantly). VGA and FROC discordant results should be attributed to the different clinical task addressed. The method to use for image-processing assessment depends on the clinical task tested.

  18. Digital image inpainting and microscopy imaging.

    PubMed

    Stanciu, Stefan G; Hristu, Radu; Stanciu, George A

    2011-11-01

    A considerable amount of image processing techniques known as inpainting techniques have been recently developed aiming to provide solutions for filling in missing or damaged regions in a digital image. Typical such techniques reconstruct a defined area by using information from its neighborhood, for example, by completing inside the missing region the isophote lines arriving at its boundaries. In this article, we show that inpainting techniques have considerable potential usefulness in microscopy imaging, even though experimenting and using them in this domain has been almost entirely neglected up until now. In this purpose, we experiment the "curvature-preserving" partial differential equations as a solution to inpainting regions in images collected by several optical and scanning probe microscopy techniques. The results achieved are presented along with a discussion on typical problematic scenarios of microscopy imaging for which this type of techniques can provide a viable solution. Copyright © 2011 Wiley Periodicals, Inc.

  19. 3D digital image processing for biofilm quantification from confocal laser scanning microscopy: Multidimensional statistical analysis of biofilm modeling

    NASA Astrophysics Data System (ADS)

    Zielinski, Jerzy S.

    The dramatic increase in number and volume of digital images produced in medical diagnostics, and the escalating demand for rapid access to these relevant medical data, along with the need for interpretation and retrieval has become of paramount importance to a modern healthcare system. Therefore, there is an ever growing need for processed, interpreted and saved images of various types. Due to the high cost and unreliability of human-dependent image analysis, it is necessary to develop an automated method for feature extraction, using sophisticated mathematical algorithms and reasoning. This work is focused on digital image signal processing of biological and biomedical data in one- two- and three-dimensional space. Methods and algorithms presented in this work were used to acquire data from genomic sequences, breast cancer, and biofilm images. One-dimensional analysis was applied to DNA sequences which were presented as a non-stationary sequence and modeled by a time-dependent autoregressive moving average (TD-ARMA) model. Two-dimensional analyses used 2D-ARMA model and applied it to detect breast cancer from x-ray mammograms or ultrasound images. Three-dimensional detection and classification techniques were applied to biofilm images acquired using confocal laser scanning microscopy. Modern medical images are geometrically arranged arrays of data. The broadening scope of imaging as a way to organize our observations of the biophysical world has led to a dramatic increase in our ability to apply new processing techniques and to combine multiple channels of data into sophisticated and complex mathematical models of physiological function and dysfunction. With explosion of the amount of data produced in a field of biomedicine, it is crucial to be able to construct accurate mathematical models of the data at hand. Two main purposes of signal modeling are: data size conservation and parameter extraction. Specifically, in biomedical imaging we have four key problems

  20. Digital diagnosis of medical images

    NASA Astrophysics Data System (ADS)

    Heinonen, Tomi; Kuismin, Raimo; Jormalainen, Raimo; Dastidar, Prasun; Frey, Harry; Eskola, Hannu

    2001-08-01

    The popularity of digital imaging devices and PACS installations has increased during the last years. Still, images are analyzed and diagnosed using conventional techniques. Our research group begun to study the requirements for digital image diagnostic methods to be applied together with PACS systems. The research was focused on various image analysis procedures (e.g., segmentation, volumetry, 3D visualization, image fusion, anatomic atlas, etc.) that could be useful in medical diagnosis. We have developed Image Analysis software (www.medimag.net) to enable several image-processing applications in medical diagnosis, such as volumetry, multimodal visualization, and 3D visualizations. We have also developed a commercial scalable image archive system (ActaServer, supports DICOM) based on component technology (www.acta.fi), and several telemedicine applications. All the software and systems operate in NT environment and are in clinical use in several hospitals. The analysis software have been applied in clinical work and utilized in numerous patient cases (500 patients). This method has been used in the diagnosis, therapy and follow-up in various diseases of the central nervous system (CNS), respiratory system (RS) and human reproductive system (HRS). In many of these diseases e.g. Systemic Lupus Erythematosus (CNS), nasal airways diseases (RS) and ovarian tumors (HRS), these methods have been used for the first time in clinical work. According to our results, digital diagnosis improves diagnostic capabilities, and together with PACS installations it will become standard tool during the next decade by enabling more accurate diagnosis and patient follow-up.

  1. Evaluation of a novel laparoscopic camera for characterization of renal ischemia in a porcine model using digital light processing (DLP) hyperspectral imaging

    NASA Astrophysics Data System (ADS)

    Olweny, Ephrem O.; Tan, Yung K.; Faddegon, Stephen; Jackson, Neil; Wehner, Eleanor F.; Best, Sara L.; Park, Samuel K.; Thapa, Abhas; Cadeddu, Jeffrey A.; Zuzak, Karel J.

    2012-03-01

    Digital light processing hyperspectral imaging (DLP® HSI) was adapted for use during laparoscopic surgery by coupling a conventional laparoscopic light guide with a DLP-based Agile Light source (OL 490, Optronic Laboratories, Orlando, FL), incorporating a 0° laparoscope, and a customized digital CCD camera (DVC, Austin, TX). The system was used to characterize renal ischemia in a porcine model.

  2. [A preliminary clinical study on endoscopic measurement of lesion area with the method of digital image processing technology].

    PubMed

    Zhang, Lei; Wang, Zhihua; Fu, Zhongqian; Fang, Pengcheng; Ling, Kai; Xu, Jianming; Kong, Derun; Xu, Zhangwei

    2013-10-01

    It is of great importance to measure the lesion area in scientific research and clinical practice. The present study aims to solve barrel distortion and measure lesion area with the technology of computer visualization. With the ultimate purpose to obtain the precise lesion area, the study, based on the original endoscopy system and digital image processing technology, dealt with the correction of barrel distortion by lens adjustment, calculated the gastric ulcer area with the aid of Qt database and finally developed an image processing software--Endoscope Assistant (EAS). The results showed that the EAS was accurate in vitro. It was employed to measure the gastric ulcer area of 45 patients and the results were compared with the traditional formula method. It could be well concluded that this technology is safe, accurate and economical for measuring gastric ulcer area.

  3. Comparison of visual grading and free-response ROC analyses for assessment of image-processing algorithms in digital mammography

    PubMed Central

    Zanca, F; Van Ongeval, C; Claus, F; Jacobs, J; Oyen, R; Bosmans, H

    2012-01-01

    Objective To compare two methods for assessment of image-processing algorithms in digital mammography: free-response receiver operating characteristic (FROC) for the specific task of microcalcification detection and visual grading analysis (VGA). Methods The FROC study was conducted prior to the VGA study reported here. 200 raw data files of low breast density (Breast Imaging–Reporting and Data System I–II) mammograms (Novation DR, Siemens, Germany)—100 of which abnormal—were processed by four image-processing algorithms: Raffaello (IMS, Bologna, Italy), Sigmoid (Sectra, Linköping, Sweden), and OpView v. 2 and v. 1 (Siemens, Erlangen, Germany). Four radiologists assessed the mammograms for the detection of microcalcifications. 8 months after the FROC study, a subset (200) of the 800 images was reinterpreted by the same radiologists, using the VGA methodology in a side-by-side approach. The VGA grading was based on noise, saturation, contrast, sharpness and confidence with the image in terms of normal structures. Ordinal logistic regression was applied; OpView v. 1 was the reference processing algorithm. Results In the FROC study all algorithms performed better than OpView v. 1. From the current VGA study and for confidence with the image, Sigmoid and Raffaello were significantly worse (p<0.001) than OpView v. 1; OpView v. 2 was significantly better (p=0.01). For the image quality criteria, results were mixed; Raffaello and Sigmoid for example were better than OpView v. 1 for sharpness and contrast (although not always significantly). Conclusion VGA and FROC discordant results should be attributed to the different clinical task addressed. Advances in knowledge The method to use for image-processing assessment depends on the clinical task tested. PMID:22844032

  4. Surface defect detection in tiling Industries using digital image processing methods: analysis and evaluation.

    PubMed

    Karimi, Mohammad H; Asemani, Davud

    2014-05-01

    Ceramic and tile industries should indispensably include a grading stage to quantify the quality of products. Actually, human control systems are often used for grading purposes. An automatic grading system is essential to enhance the quality control and marketing of the products. Since there generally exist six different types of defects originating from various stages of tile manufacturing lines with distinct textures and morphologies, many image processing techniques have been proposed for defect detection. In this paper, a survey has been made on the pattern recognition and image processing algorithms which have been used to detect surface defects. Each method appears to be limited for detecting some subgroup of defects. The detection techniques may be divided into three main groups: statistical pattern recognition, feature vector extraction and texture/image classification. The methods such as wavelet transform, filtering, morphology and contourlet transform are more effective for pre-processing tasks. Others including statistical methods, neural networks and model-based algorithms can be applied to extract the surface defects. Although, statistical methods are often appropriate for identification of large defects such as Spots, but techniques such as wavelet processing provide an acceptable response for detection of small defects such as Pinhole. A thorough survey is made in this paper on the existing algorithms in each subgroup. Also, the evaluation parameters are discussed including supervised and unsupervised parameters. Using various performance parameters, different defect detection algorithms are compared and evaluated. Copyright © 2013 ISA. Published by Elsevier Ltd. All rights reserved.

  5. Digital signal processing

    NASA Astrophysics Data System (ADS)

    Oppenheim, A. V.; Baggeroer, A. B.; Lim, J. S.; Musicus, B. R.; Mook, D. R.; Duckworth, G. L.; Bordley, T. E.; Curtis, S. R.; Deadrick, D. S.; Dove, W. P.

    1984-01-01

    Signal and image processing research projects are described. Topics include: (1) modeling underwater acoustic propagation; (2) image restoration; (3) signal reconstruction; (4) speech enhancement; (5) pitch detection; (6) spectral analysis; (7) speech synthesis; (8) speech enhancement; (9) autoregressive spectral estimation; (10) knowledge based array processing; (11) speech analysis; (12) estimating the degree of coronary stenosis with image processing; (13) automatic target detection; and (14) video conferencing.

  6. Digital imaging technology assessment: Digital document storage project

    NASA Technical Reports Server (NTRS)

    1989-01-01

    An ongoing technical assessment and requirements definition project is examining the potential role of digital imaging technology at NASA's STI facility. The focus is on the basic components of imaging technology in today's marketplace as well as the components anticipated in the near future. Presented is a requirement specification for a prototype project, an initial examination of current image processing at the STI facility, and an initial summary of image processing projects at other sites. Operational imaging systems incorporate scanners, optical storage, high resolution monitors, processing nodes, magnetic storage, jukeboxes, specialized boards, optical character recognition gear, pixel addressable printers, communications, and complex software processes.

  7. We get the algorithms of our ground truths: Designing referential databases in digital image processing.

    PubMed

    Jaton, Florian

    2017-09-01

    This article documents the practical efforts of a group of scientists designing an image-processing algorithm for saliency detection. By following the actors of this computer science project, the article shows that the problems often considered to be the starting points of computational models are in fact provisional results of time-consuming, collective and highly material processes that engage habits, desires, skills and values. In the project being studied, problematization processes lead to the constitution of referential databases called 'ground truths' that enable both the effective shaping of algorithms and the evaluation of their performances. Working as important common touchstones for research communities in image processing, the ground truths are inherited from prior problematization processes and may be imparted to subsequent ones. The ethnographic results of this study suggest two complementary analytical perspectives on algorithms: (1) an 'axiomatic' perspective that understands algorithms as sets of instructions designed to solve given problems computationally in the best possible way, and (2) a 'problem-oriented' perspective that understands algorithms as sets of instructions designed to computationally retrieve outputs designed and designated during specific problematization processes. If the axiomatic perspective on algorithms puts the emphasis on the numerical transformations of inputs into outputs, the problem-oriented perspective puts the emphasis on the definition of both inputs and outputs.

  8. Evaluation of physical integrity of lipid bilayer under oxidative stress: application of fluorescence microscopy and digital image processing.

    PubMed

    Liang, Ran; Zhang, Jian-Ping; Skibsted, Leif H

    2015-01-01

    Membrane damage as a result of oxidative stress is quantified using digital image heterogeneity analysis of single giant unilamellar vesicles (GUVs) composed of soy phosphatidylcholine (PC), which were found to undergo budding when containing chlorophyll a (Chla) as photosensitizer in the lipid bilayer. Based on digital image heterogeneity analysis, a dimensionless scalar parameter "entropy" for the budding process was found to change linearly during an initial budding stage. Photo-induced peroxidation of PC to form linoleoyl hydroperoxides, further leading to domains of higher polarities in GUVs, was suggested to initiate the budding process. The effect on budding process of GUVs was suggested for use in assays for evaluation of potential protectors of lipid bilayer integrity under oxidative stress, and "entropy" seemed to be a valid descriptor of such membranal integrity. The one-step procedure for quantification of prooxidative effects and antioxidative protection provided by drug candidates and potential food ingredients in membranes could be easily automated for direct measurement of oxidative and antioxidative effects on cellular integrity.

  9. Measurement of steady and transient liquid coiling with high-speed video and digital image processing

    NASA Astrophysics Data System (ADS)

    Mier, Frank Austin; Bhakta, Raj; Castano, Nicolas; Thackrah, Joshua; Marquis, Tyler; Garcia, John; Hargather, Michael

    2016-11-01

    Liquid coiling occurs as a gravitationally-accelerated viscous fluid flows into a stagnant reservoir causing a localized accumulation of settling material, commonly designated as stack. This flow is broadly characterized by a vertical rope of liquid, the tail, flowing into the stack in a coiled motion with frequency defined parametrically within four different flow regimes. These regimes are defined as viscous, gravitational, inertial-gravitational, and inertial. Relations include parameters such as flow rate, drop height, rope radius, gravitational acceleration, and kinematic viscosity. While previous work on the subject includes high speed imaging, only basic and often averaged measurements have been taken by visual inspection of images. Through the implementation of additional image processing routines in MATLAB, time resolved measurements are taken on coiling frequency, tail diameter, stack diameter and height. Synchronization between a high speed camera and stepper motor driven syringe pump provides accurate correlation with flow rate. Additionally, continuous measurement of unsteady transition between flow regimes is visualized and quantified. This capability allows a deeper experimental understanding of processes involved in the liquid coiling phenomenon.

  10. Continuous Representations of Digital Images.

    DTIC Science & Technology

    1985-10-01

    adjacency topology on a 2D digital image S is well represented by the standard Euclidean topology on F (S ) (resp. U (S )). The topological spaces F(S) and U...space R as primitive approximation of a 2D digital image S by con- tinuous topological spaces . This space F (S) is not new. In fact, it has always been

  11. Should processed or raw image data be used in mammographic image quality analyses? A comparative study of three full-field digital mammography systems.

    PubMed

    Borg, Mark; Badr, Ishmail; Royle, Gary

    2015-01-01

    The purpose of this study is to compare a number of measured image quality parameters using processed and unprocessed or raw images in two full-field direct digital units and one computed radiography mammography system. This study shows that the difference between raw and processed image data is system specific. The results have shown that there are no significant differences between raw and processed data in the mean threshold contrast values using the contrast-detail mammography phantom in all the systems investigated; however, these results cannot be generalised to all available systems. Notable differences were noted in contrast-to-noise ratios and in other tests including: response function, modulation transfer function , noise equivalent quanta, normalised noise power spectra and detective quantum efficiency as specified in IEC 62220-1-2. Consequently, the authors strongly recommend the use of raw data for all image quality analyses in digital mammography. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  12. Using UAVs and digital image processing to quantify areas of soil and vegetation

    NASA Astrophysics Data System (ADS)

    Chaves, A. A.; La Scalea, R. A.; Colturato, A. B.; Kawabata, C. L. O.; Furtado, E. L.; Castelo Branco, K. R. L. J.

    2015-09-01

    Unmanned aerial vehicles (UAVs) are becoming a very popular tool for remote sensing and crop monitoring. They are more easily deployed, cheaper and can obtain images with higher spatial-resolution than satellites. Some small, commercial UAVs can obtain images with spatial-resolution as low as 1.5cm per pixel. This opens up the range of possible remote sensing and monitoring applications. Moreover, they can cover large areas in very little time, such as 50 ha in about 20min, which makes UAVs the ideal tool for monitoring large farms and plantations. On the other hand, it is important to know precisely the area covered by farms in order to avoid invasion of other properties or preserved areas, and also to detect flaws in the plantation area. However, it is difficult to measure planted areas in some cases, such as Eucalyptus crops. Therefore, this paper aims to evaluate the use of UAV imagery for precise area measurement in Eucalyptus crops. We developed an image-processing algorithm to segment regions of soil, low biomass and high biomass and tested it on a Eucalyptus plantation in the city of Lenis Paulista -SP, Brazil. Results show that the area quantification is very accurate especially for bare soil regions and this method can be used to estimate areas in other scenarios.

  13. Digital image processing techniques for enhancement and classification of SeaMARC II side scan sonar imagery

    NASA Astrophysics Data System (ADS)

    Reed, Thomas Beckett, IV; Hussong, Donald

    1989-06-01

    The recent growth in the production rate of digital side scan sonar images, coupled with the rapid expansion of systematic seafloor exploration programs, has created a need for fast and quantitative means of processing seafloor imagery. Computer-aided analytical techniques fill this need. A number of numerical techniques used to enhance and classify imagery produced by SeaMARC II, a long-range combination side scan sonar, and bathymetric seafloor mapping system are documented. Three categories of techniques are presented: (1) preprocessing corrections (radiometric and geometric), (2) feature extraction, and (3) image segmentation and classification. An introduction to the concept of "feature vectors" is provided, along with an explanation of the method of evaluation of a texture feature vector based upon gray-level co-occurrence matrices (GLCM). An alternative to the a priori texel (texture element) subdivision of images is presented in the form of region growing and texture analysis (REGATA). This routine provides a texture map of spatial resolution superior to that obtainable with arbitrarily assigned texel boundaries and minimizes the possibility of mixed texture signals due to the combination of two or more textures in an arbitrarily assigned texel. Computer classification of these textural features extracted via the GLCM technique results in transformation of images into maps of image texture. These maps may either be interpreted in terms of the theoretical relationships shown between texture signatures and wavelength or converted to geologic maps by correlation of texture signatures with ground truth data. These techniques are applied to SeaMARC II side scan sonar imagery from a variety of geologic environments, including lithified and nonlithified sedimentary formations, volcanic and sedimentary debris flows, and crystalline basaltic outcrops. Application of the above processing steps provided not only superior images for both subjective and quantitative

  14. Photographic image enhancement and processing

    NASA Technical Reports Server (NTRS)

    Lockwood, H. E.

    1977-01-01

    Scientists using aerial imagery frequently desire image processing or enhancement of that imagery to aid them in data analysis. Sophisticated digital image processing techniques are currently employed in many applications where the data is recorded in digital format, where processing hardware and programs are available. Aerial photographic imagery poses a problem in the magnitude of the digitization processing. Photographic image processing analogous to many available digital techniques is being employed by scientific investigators. Those techniques which may be applied in a cost effective manner to processing of aerial photographic imagery are described here.

  15. The influence of the microscope lamp filament colour temperature on the process of digital images of histological slides acquisition standardization.

    PubMed

    Korzynska, Anna; Roszkowiak, Lukasz; Pijanowska, Dorota; Kozlowski, Wojciech; Markiewicz, Tomasz

    2014-01-01

    The aim of this study is to compare the digital images of the tissue biopsy captured with optical microscope using bright field technique under various light conditions. The range of colour's variation in immunohistochemically stained with 3,3'-Diaminobenzidine and Haematoxylin tissue samples is immense and coming from various sources. One of them is inadequate setting of camera's white balance to microscope's light colour temperature. Although this type of error can be easily handled during the stage of image acquisition, it can be eliminated with use of colour adjustment algorithms. The examination of the dependence of colour variation from microscope's light temperature and settings of the camera is done as an introductory research to the process of automatic colour standardization. Six fields of view with empty space among the tissue samples have been selected for analysis. Each field of view has been acquired 225 times with various microscope light temperature and camera white balance settings. The fourteen randomly chosen images have been corrected and compared, with the reference image, by the following methods: Mean Square Error, Structural SIMilarity and visual assessment of viewer. For two types of backgrounds and two types of objects, the statistical image descriptors: range, median, mean and its standard deviation of chromaticity on a and b channels from CIELab colour space, and luminance L, and local colour variability for objects' specific area have been calculated. The results have been averaged for 6 images acquired in the same light conditions and camera settings for each sample. The analysis of the results leads to the following conclusions: (1) the images collected with white balance setting adjusted to light colour temperature clusters in certain area of chromatic space, (2) the process of white balance correction for images collected with white balance camera settings not matched to the light temperature moves image descriptors into proper

  16. High-throughput screening of high Monascus pigment-producing strain based on digital image processing.

    PubMed

    Xia, Meng-lei; Wang, Lan; Yang, Zhi-xia; Chen, Hong-zhang

    2016-04-01

    This work proposed a new method which applied image processing and support vector machine (SVM) for screening of mold strains. Taking Monascus as example, morphological characteristics of Monascus colony were quantified by image processing. And the association between the characteristics and pigment production capability was determined by SVM. On this basis, a highly automated screening strategy was achieved. The accuracy of the proposed strategy is 80.6 %, which is compatible with the existing methods (81.1 % for microplate and 85.4 % for flask). Meanwhile, the screening of 500 colonies only takes 20-30 min, which is the highest rate among all published results. By applying this automated method, 13 strains with high-predicted production were obtained and the best one produced as 2.8-fold (226 U/mL) of pigment and 1.9-fold (51 mg/L) of lovastatin compared with the parent strain. The current study provides us with an effective and promising method for strain improvement.

  17. Parallel Analog-to-Digital Image Processor

    NASA Technical Reports Server (NTRS)

    Lokerson, D. C.

    1987-01-01

    Proposed integrated-circuit network of many identical units convert analog outputs of imaging arrays of x-ray or infrared detectors to digital outputs. Converter located near imaging detectors, within cryogenic detector package. Because converter output digital, lends itself well to multiplexing and to postprocessing for correction of gain and offset errors peculiar to each picture element and its sampling and conversion circuits. Analog-to-digital image processor is massively parallel system for processing data from array of photodetectors. System built as compact integrated circuit located near local plane. Buffer amplifier for each picture element has different offset.

  18. Photography/Digital Imaging: Parallel & Paradoxical Histories.

    ERIC Educational Resources Information Center

    Witte, Mary Stieglitz

    With the introduction of photography and photomechanical printing processes in the 19th century, the first age of machine pictures and reproductions emerged. The 20th century introduced computer image processing systems, creating a digital imaging revolution. Rather than concentrating on the adversarial aspects of the computer's influence on…

  19. Far-field focusing of laser beam based on digital image processing techniques

    NASA Astrophysics Data System (ADS)

    Zhang, He-yong; Zhao, Shuai; Guo, Jin; Liu, Li-sheng; Tian, Yu-zhen

    2010-11-01

    In order to lead the laser beam transmit in the atmosphere convergently, an experiment of laser focus at the distance of 450m and 300m has been operated in the outdoor place. The actual manipulations are as follows: Firstly, the laser was collimated by a beam expander, then the near-parallel laser beam was transmitted with a Galileo telescope system, and the distance between the concave lens and the convex lens can be tuned through a precise displacement platform, so the focus of the system changed due to the tiny displacement of the concave lens. Secondly, the average power of the laser spot can be measured using power meter, the power is 47.67mW and the standard deviation is 0.67mW while the focal length is 450m. Thirdly, the energy distribution was found through the laser beam analyzer. The spot images were saved using the beam analyzer, then the saved image can be processed with Matlab software afterwards. The function named EDGE and Sobel operator was used in the pre-processing of the saved image, then method of median filter was used in the course of image de-noising and 53H filter was adopted in the signal analysis. The diameter of laser spot was obtained by the method above, the diameter is 5.56mm and the standard deviation is 0.24mm. The spot center excursion is 0.56mm, it is 10.43% of the total diameter of the laser spot. At last, the key factors of the energy dissipation in the focusing system can be summarized as follows: restriction of the diffraction limit, attenuation in the atmosphere, geometrical aberration of optical system, and the diffraction limit and the geometrical aberration are significant in the three factors above, so we can reduce the impact of the both factors during the design of optical system. The reliable referenced data of the system design can be acquired through the primary experiment research.

  20. Nephropathology consultation via digitized images.

    PubMed

    Cronenberger, J H; Hsiao, H; Falk, R J; Jennette, J C

    1992-12-17

    Investigations into a digitized image communications system were prompted by a need to bring expert consultation to physicians in community practice. Pathologists desired the capability to concomitantly view, annotate, and discuss images with referring physicians at distant sites. Methods included evaluation of the human and procedural domain into which the system was to be integrated. The GDCN computer consultation system has the consultant nephropathologist first evaluate the processed biopsy slides, digitize representative images, transmit them with the diagnosis to referring nephrologist, and, finally, conduct an interactive consultation and review of the biopsy and case. Image resolution and compression variables must be set for each individual medical consulting application. For the GDCN, it was found that the 640 x 496 x unlimited color with compression ratios not exceeding 1:32 are acceptable. An obvious improvement of this computerized system over the noncomputerized review sessions is the ability to immediately share and discuss a new image that had not been previously sent. In the old noncomputerized consultation, only images that had been mailed could be discussed. The computerized sessions allow transmission (10 sec) of a new image that the consultation might demand. The computerized sessions also provide the ability to show the referring nephrologist an area of biopsy interest that the pathologist had not previously transmitted. Biopsy slides can be viewed during the consultation, an area digitized, and that image transmitted to the nephrologist during the consultation. Hardware and costs for the sending station were: [table: see text] This system far exceeds the requirements for this particular application; however, it is sufficient to support future, higher-technology computer applications. If necessary, this same system could be used with a less expensive computer, a less expensive camera, software compression, and a single monitor. These

  1. Application of digital image processing to a beta-gauge for determining mass concentration of suspending particulate matter in atmosphere.

    PubMed

    Gotoh, T

    1992-05-01

    A two-dimensional image of the mass concentration of suspending particulate matter (SPM) collected on Millipore filter paper was photographed with Ultrofilm-3H. The printed paper image was transformed into a digital image (256 x 256 pixels) with 256 gray levels. Two results were obtained. The averaged values of gray level over all pixels of the digital image was found to correlate with the mass value measured by a beta-gauge. The characteristical range of the digital image which was transformed to frequency by two-dimensional fast fourier transformation was found in the low frequency. It was presumed to relate to SPM from anthropogenic sources because the SPMs usually show higher density and smaller particle size than SPMs from natural sources.

  2. Processing Of Binary Images

    NASA Astrophysics Data System (ADS)

    Hou, H. S.

    1985-07-01

    An overview of the recent progress in the area of digital processing of binary images in the context of document processing is presented here. The topics covered include input scan, adaptive thresholding, halftoning, scaling and resolution conversion, data compression, character recognition, electronic mail, digital typography, and output scan. Emphasis has been placed on illustrating the basic principles rather than descriptions of a particular system. Recent technology advances and research in this field are also mentioned.

  3. Geologic analyses of LANDSAT-1 multispectral imagery of a possible power plant site employing digital and analog image processing. [in Pennsylvania

    NASA Technical Reports Server (NTRS)

    Lovegreen, J. R.; Prosser, W. J.; Millet, R. A.

    1975-01-01

    A site in the Great Valley subsection of the Valley and Ridge physiographic province in eastern Pennsylvania was studied to evaluate the use of digital and analog image processing for geologic investigations. Ground truth at the site was obtained by a field mapping program, a subsurface exploration investigation and a review of available published and unpublished literature. Remote sensing data were analyzed using standard manual techniques. LANDSAT-1 imagery was analyzed using digital image processing employing the multispectral Image 100 system and using analog color processing employing the VP-8 image analyzer. This study deals primarily with linears identified employing image processing and correlation of these linears with known structural features and with linears identified manual interpretation; and the identification of rock outcrops in areas of extensive vegetative cover employing image processing. The results of this study indicate that image processing can be a cost-effective tool for evaluating geologic and linear features for regional studies encompassing large areas such as for power plant siting. Digital image processing can be an effective tool for identifying rock outcrops in areas of heavy vegetative cover.

  4. Interactive digital image manipulation system

    NASA Technical Reports Server (NTRS)

    Henze, J.; Dezur, R.

    1975-01-01

    The system is designed for manipulation, analysis, interpretation, and processing of a wide variety of image data. LANDSAT (ERTS) and other data in digital form can be input directly into the system. Photographic prints and transparencies are first converted to digital form with an on-line high-resolution microdensitometer. The system is implemented on a Hewlett-Packard 3000 computer with 128 K bytes of core memory and a 47.5 megabyte disk. It includes a true color display monitor, with processing memories, graphics overlays, and a movable cursor. Image data formats are flexible so that there is no restriction to a given set of remote sensors. Conversion between data types is available to provide a basis for comparison of the various data. Multispectral data is fully supported, and there is no restriction on the number of dimensions. In this way multispectral data collected at more than one point in time may simply be treated as a data collected with twice (three times, etc.) the number of sensors. There are various libraries of functions available to the user: processing functions, display functions, system functions, and earth resources applications functions.

  5. Interactive digital image manipulation system

    NASA Technical Reports Server (NTRS)

    Henze, J.; Dezur, R.

    1975-01-01

    The system is designed for manipulation, analysis, interpretation, and processing of a wide variety of image data. LANDSAT (ERTS) and other data in digital form can be input directly into the system. Photographic prints and transparencies are first converted to digital form with an on-line high-resolution microdensitometer. The system is implemented on a Hewlett-Packard 3000 computer with 128 K bytes of core memory and a 47.5 megabyte disk. It includes a true color display monitor, with processing memories, graphics overlays, and a movable cursor. Image data formats are flexible so that there is no restriction to a given set of remote sensors. Conversion between data types is available to provide a basis for comparison of the various data. Multispectral data is fully supported, and there is no restriction on the number of dimensions. In this way multispectral data collected at more than one point in time may simply be treated as a data collected with twice (three times, etc.) the number of sensors. There are various libraries of functions available to the user: processing functions, display functions, system functions, and earth resources applications functions.

  6. Topographic analysis for tectonic geomorphology using digital image processing of elevation data from the Mississippi embayment and adjacent areas

    SciTech Connect

    Mayer, L. . Dept. of Geology)

    1993-03-01

    Image processing of digital elevation data provides a framework within which to evaluate the relative importance of tectonic and erosional signatures on the landscape. Shaded relief imaging of the elevation data illuminates regional topographic features coincident with the physiographic provinces bounding the Mississippi embayment portion of the Coastal Plain: the Ozark Plateaus and Ouachitas on the west, the Central Lowland on the north, and the Interior Low Plateaus on the east. Grayscale or colors from custom color lookup tables are assigned based on elevation. Stretching can be used to enhance a particular elevation range while spatial convolution kernels can be used to provide a robust and rapid means of designing high- and low-pass filters for the purpose of restricting the frequency range examined. Thresholding the elevation ranges and assigning boundaries of the resultant binary images allow for the rapid delineation of topographic contour lines and permits quantization of planform geometry. Forty one-degree by 30-minute quadrangles have been imaged for the purpose of delineating topographic features of possible tectonic origin.

  7. Materials characterization through quantitative digital image analysis

    SciTech Connect

    J. Philliber; B. Antoun; B. Somerday; N. Yang

    2000-07-01

    A digital image analysis system has been developed to allow advanced quantitative measurement of microstructural features. This capability is maintained as part of the microscopy facility at Sandia, Livermore. The system records images digitally, eliminating the use of film. Images obtained from other sources may also be imported into the system. Subsequent digital image processing enhances image appearance through the contrast and brightness adjustments. The system measures a variety of user-defined microstructural features--including area fraction, particle size and spatial distributions, grain sizes and orientations of elongated particles. These measurements are made in a semi-automatic mode through the use of macro programs and a computer controlled translation stage. A routine has been developed to create large montages of 50+ separate images. Individual image frames are matched to the nearest pixel to create seamless montages. Results from three different studies are presented to illustrate the capabilities of the system.

  8. High sensitive and selective HPTLC method assisted by digital image processing for simultaneous determination of catecholamines and related drugs.

    PubMed

    Sima Tuhuţiu, Ioana Anamaria; Casoni, Dorina; Sârbu, Costel

    2013-09-30

    A highly sensitive and selective thin layer chromatographic (TLC) method was developed for simultaneous determination of catecholamines and their related drugs using a new detection method and digital image processing of chromatographic plates. For the quantitative evaluation of the investigated compounds, the chromatographic separation was followed by spraying the plate with 0.02% solution of 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) in ethanol. The BioDit Thin Layer Chromatography (TLC) Scanner device and advanced specific software (ImageDecipher-TLC, Sorbfil TLC Videodensitometer and JustTLC) were used for the detection and quantification of chromatographic spots. For an accurate determination, the RGB colored images of the bright-white spots detected against a purple background were inverted and processed after their conversion into green scale. The results showed a strongly linear correlation between area (R(2)>0.99) and volume (R(2)>0.99) of spots and concentration of investigated compounds in all cases. The limit of detection (LOD) and the limit of quantification (LOQ) were below 49.3 ng/spot and 69.6 ng/spot respectively in all cases. The evaluation of the method was performed using different pharmaceutical samples spiked with the investigated amines and validated with respect to accuracy and precision. Copyright © 2013 Elsevier B.V. All rights reserved.

  9. Digital radiography: image quality and radiation dose.

    PubMed

    Seibert, J Anthony

    2008-11-01

    Digital radiography devices, rapidly replacing analog screen-film detectors, are now common in diagnostic radiological imaging, where implementation has been accelerated by the commodity status of electronic imaging and display systems. The shift from narrow latitude, fixed-speed screen-film detectors to wide latitude, variable-speed digital detectors has created a flexible imaging system that can easily result in overexposures to the patient without the knowledge of the operator, thus potentially increasing the radiation burden of the patient population from radiographic examinations. In addition, image processing can be inappropriately applied causing inconsistent or artifactual appearance of anatomy, which can lead to misdiagnosis. On the other hand, many advantages can be obtained from the variable-speed digital detector, such as an ability to lower dose in many examinations, image post-processing for disease-specific conditions, display flexibility to change the appearance of the image and aid the physician in making a differential diagnosis, and easy access to digital images. An understanding of digital radiography is necessary to minimize the possibility of overexposures and inconsistent results, and to achieve the principle of as low as reasonably achievable (ALARA) for the safe and effective care of all patients. Thus many issues must be considered for optimal implementation of digital radiography, as reviewed in this article.

  10. Using Digital Photography and Image Processing for the Creation of Notes from the Blackboard

    ERIC Educational Resources Information Center

    Bruun, Erik

    2009-01-01

    This paper describes a teaching experiment involving the use of a combination of traditional chalkboard and digital photography in order to produce lecture notes from the blackboard. During lecturing the blackboard is used instead of transparencies or PowerPoint presentations. This reduces the speed of presentation and leaves room for…

  11. ISSUES IN DIGITAL IMAGE PROCESSING OF AERIAL PHOTOGRAPHY FOR MAPPING SUBMERSED AQUATIC VEGETATION

    EPA Science Inventory

    The paper discusses the numerous issues that needed to be addressed when developing a methodology for mapping Submersed Aquatic Vegetation (SAV) from digital aerial photography. Specifically, we discuss 1) choice of film; 2) consideration of tide and weather constraints; 3) in-s...

  12. Using Digital Photography and Image Processing for the Creation of Notes from the Blackboard

    ERIC Educational Resources Information Center

    Bruun, Erik

    2009-01-01

    This paper describes a teaching experiment involving the use of a combination of traditional chalkboard and digital photography in order to produce lecture notes from the blackboard. During lecturing the blackboard is used instead of transparencies or PowerPoint presentations. This reduces the speed of presentation and leaves room for…

  13. ISSUES IN DIGITAL IMAGE PROCESSING OF AERIAL PHOTOGRAPHY FOR MAPPING SUBMERSED AQUATIC VEGETATION

    EPA Science Inventory

    The paper discusses the numerous issues that needed to be addressed when developing a methodology for mapping Submersed Aquatic Vegetation (SAV) from digital aerial photography. Specifically, we discuss 1) choice of film; 2) consideration of tide and weather constraints; 3) in-s...

  14. Accuracy is in the eyes of the pathologist: The visual interpretive process and diagnostic accuracy with digital whole slide images.

    PubMed

    Brunyé, Tad T; Mercan, Ezgi; Weaver, Donald L; Elmore, Joann G

    2017-02-01

    Digital whole slide imaging is an increasingly common medium in pathology, with application to education, telemedicine, and rendering second opinions. It has also made it possible to use eye tracking devices to explore the dynamic visual inspection and interpretation of histopathological features of tissue while pathologists review cases. Using whole slide images, the present study examined how a pathologist's diagnosis is influenced by fixed case-level factors, their prior clinical experience, and their patterns of visual inspection. Participating pathologists interpreted one of two test sets, each containing 12 digital whole slide images of breast biopsy specimens. Cases represented four diagnostic categories as determined via expert consensus: benign without atypia, atypia, ductal carcinoma in situ (DCIS), and invasive cancer. Each case included one or more regions of interest (ROIs) previously determined as of critical diagnostic importance. During pathologist interpretation we tracked eye movements, viewer tool behavior (zooming, panning), and interpretation time. Models were built using logistic and linear regression with generalized estimating equations, testing whether variables at the level of the pathologists, cases, and visual interpretive behavior would independently and/or interactively predict diagnostic accuracy and efficiency. Diagnostic accuracy varied as a function of case consensus diagnosis, replicating earlier research. As would be expected, benign cases tended to elicit false positives, and atypia, DCIS, and invasive cases tended to elicit false negatives. Pathologist experience levels, case consensus diagnosis, case difficulty, eye fixation durations, and the extent to which pathologists' eyes fixated within versus outside of diagnostic ROIs, all independently or interactively predicted diagnostic accuracy. Higher zooming behavior predicted a tendency to over-interpret benign and atypia cases, but not DCIS cases. Efficiency was not predicted

  15. Digital Imaging Investigations.

    ERIC Educational Resources Information Center

    Keith, Ronald L.; Saunders, David K.; Yanik, Elizabeth G.

    2003-01-01

    Explains how digital technology can be used as a tool for teaching students the skills of observation, questioning, information gathering, classifying, predicting, and hypothesis testing. (Author/SOE)

  16. Digital video image processing from dental operating microscope in endodontic treatment.

    PubMed

    Suehara, Masataka; Nakagawa, Kan-Ichi; Aida, Natsuko; Ushikubo, Toshihiro; Morinaga, Kazuki

    2012-01-01

    Recently, optical microscopes have been used in endodontic treatment, as they offer advantages in terms of magnification, illumination, and documentation. Documentation is particularly important in presenting images to patients, and can take the form of both still images and motion video. Although high-quality still images can be obtained using a 35-mm film or CCD camera, the quality of still images produced by a video camera is significantly lower. The purpose of this study was to determine the potential of RegiStax in obtaining high-quality still images from a continuous video stream from an optical microscope. Video was captured continuously and sections with the highest luminosity chosen for frame alignment and stacking using the RegiStax program. The resulting stacked images were subjected to wavelet transformation. The results indicate that high-quality images with a large depth of field could be obtained using this method.

  17. Introduction to computer image processing

    NASA Technical Reports Server (NTRS)

    Moik, J. G.

    1973-01-01

    Theoretical backgrounds and digital techniques for a class of image processing problems are presented. Image formation in the context of linear system theory, image evaluation, noise characteristics, mathematical operations on image and their implementation are discussed. Various techniques for image restoration and image enhancement are presented. Methods for object extraction and the problem of pictorial pattern recognition and classification are discussed.

  18. Digital processing clock

    NASA Technical Reports Server (NTRS)

    Phillips, D. H.

    1982-01-01

    Tthe digital processing clock SG 1157/U is described. It is compatible with the PTTI world where it can be driven by an external cesium source. Built-in test equipment shows synchronization with cesium through 1 pulse per second. It is built to be expandable to accommodate future time-keeping needs of the Navy as well as any other time ordered functions. Examples of this expandibility are the inclusion of an unmodulated XR3 time code and the 2137 modulate time code (XR3 with 1 kHz carrier).

  19. Mars Digital Image Mosaic Globe

    NASA Technical Reports Server (NTRS)

    2000-01-01

    The photomosaic that forms the base for this globe was created by merging two global digital image models (DIM's) of Mars-a medium-resolution monochrome mosaic processed to emphasize topographic features and a lower resolution color mosaic emphasizing color and albedo variations.

    The medium-resolution (1/256 or roughly 231 m/pixel) monochromatic image model was constructed from about 6,000 images having resolutions of 150-350 m/pixel and oblique illumination (Sun 20 o -45 o above the horizon). Radiometric processing was intended to suppress or remove the effects of albedo variations through the use of a high-pass divide filter, followed by photometric normalization so that the contrast of a given topographic slope would be approximately the same in all images.

    The global color mosaic was assembled at 1/64 or roughly 864 m/pixel from about 1,000 red- and green-filter images having 500-1,000 m/pixel resolution. These images were first mosaiced in groups, each taken on a single orbit of the Viking spacecraft. The orbit mosaics were then processed to remove spatially and temporally varying atmospheric haze in the overlap regions. After haze removal, the per-orbit mosaics were photometrically normalized to equalize the contrast of albedo features and mosaiced together with cosmetic seam removal. The medium-resolution DIM was used for geometric control of this color mosaic. A green-filter image was synthesized by weighted averaging of the red- and violet-filter mosaics. Finally, the product seen here was obtained by multiplying each color image by the medium-resolution monochrome image. The color balance selected for images in this map series was designed to be close to natural color for brighter, redder regions, such as Arabia Terra and the Tharsis region, but the data have been stretched so that the relatively dark regions appear darker and less red than they actually are.

    The images are presented in a projection that portrays the entire surface of Mars in a

  20. Mars Digital Image Mosaic Globe

    NASA Technical Reports Server (NTRS)

    2000-01-01

    The photomosaic that forms the base for this globe was created by merging two global digital image models (DIM's) of Mars-a medium-resolution monochrome mosaic processed to emphasize topographic features and a lower resolution color mosaic emphasizing color and albedo variations.

    The medium-resolution (1/256 or roughly 231 m/pixel) monochromatic image model was constructed from about 6,000 images having resolutions of 150-350 m/pixel and oblique illumination (Sun 20 o -45 o above the horizon). Radiometric processing was intended to suppress or remove the effects of albedo variations through the use of a high-pass divide filter, followed by photometric normalization so that the contrast of a given topographic slope would be approximately the same in all images.

    The global color mosaic was assembled at 1/64 or roughly 864 m/pixel from about 1,000 red- and green-filter images having 500-1,000 m/pixel resolution. These images were first mosaiced in groups, each taken on a single orbit of the Viking spacecraft. The orbit mosaics were then processed to remove spatially and temporally varying atmospheric haze in the overlap regions. After haze removal, the per-orbit mosaics were photometrically normalized to equalize the contrast of albedo features and mosaiced together with cosmetic seam removal. The medium-resolution DIM was used for geometric control of this color mosaic. A green-filter image was synthesized by weighted averaging of the red- and violet-filter mosaics. Finally, the product seen here was obtained by multiplying each color image by the medium-resolution monochrome image. The color balance selected for images in this map series was designed to be close to natural color for brighter, redder regions, such as Arabia Terra and the Tharsis region, but the data have been stretched so that the relatively dark regions appear darker and less red than they actually are.

    The images are presented in a projection that portrays the entire surface of Mars in a

  1. Development and evaluation of an automatic acne lesion detection program using digital image processing.

    PubMed

    Min, Seonguk; Kong, Hyoun-joong; Yoon, Chiyul; Kim, Hee Chan; Suh, Dae Hun

    2013-02-01

    Existing acne grading methods, which depend on overall impression, require a long training period and there is a high degree of variability among raters, including trained dermatologists. The use of lesion count provides fair reproducibility but the method is time consuming. New technologies in photographic equipment and software allow solutions to the problem of acne evaluation. This study was conducted to develop the automatic acne lesion program and evaluation of its usefulness. We made the conditions to optimize characterization of acne lesions and developed the counting program. Twenty-five volunteers with acne lesions were enrolled. Automated lesion counting for five subtypes of acne (papule, nodule, pustule, whitehead comedone, and blackhead comedone) was performed with image processing. The usefulness of the automatic lesion count program was assessed by a comparison with manual counting performed by an expert dermatologist. In a comparison with manual counting performed by an expert dermatologist, the sensitivity and positive predictive value of the lesion-counting program was greater than 70% for papules, nodules, pustules, and whitehead comedo. In a comparison with manual counting, findings with the use of the lesion-counting program were well correlated for papules, nodules, pustules, and whitehead comedo (r > 0.9). Automatic lesion-counting program can be a useful tool for acne severity evaluation. © 2012 John Wiley & Sons A/S.

  2. Digital processing of SEM images for the assessment of evaluation indexes of cleaning interventions on Pentelic marble surfaces

    SciTech Connect

    Moropoulou, A. Delegou, E.T.; Vlahakis, V.; Karaviti, E.

    2007-11-15

    In this work, digital processing of scanning-electron-microscopy images utilized to assess cleaning interventions applied on the Pentelic marble surfaces of the National Archaeological Museum and National Library in Athens, Greece. Beside mineralogical and chemical characterization that took place by scanning-electron-microscopy with Energy Dispersive X-ray Spectroscopy, the image-analysis program EDGE was applied for estimating three evaluation indexes of the marble micro-structure. The EDGE program was developed by the U.S. Geological Survey for the evaluation of cleaning interventions applied on Philadelphia City Hall. This computer program analyzes scanning-electron-microscopy images of stone specimens cut in cross-section for measuring the fractal dimension of the exposed surfaces, the stone near-surface fracture density, the shape factor (a surface roughness factor) and the friability index which represents the physico-chemical and physico-mechanical stability of the stone surface. The results indicated that the evaluation of the marble surface micro-structure before and after cleaning is achieved by the suggested indexes, while the performance of cleaning interventions on the marble surfaces can be assessed.

  3. Imagers for digital still photography

    NASA Astrophysics Data System (ADS)

    Bosiers, Jan; Dillen, Bart; Draijer, Cees; Manoury, Erik-Jan; Meessen, Louis; Peters, Inge

    2006-04-01

    This paper gives an overview of the requirements for, and current state-of-the-art of, CCD and CMOS imagers for use in digital still photography. Four market segments will be reviewed: mobile imaging, consumer "point-and-shoot cameras", consumer digital SLR cameras and high-end professional camera systems. The paper will also present some challenges and innovations with respect to packaging, testing, and system integration.

  4. Image display device in digital TV

    DOEpatents

    Choi, Seung Jong

    2006-07-18

    Disclosed is an image display device in a digital TV that is capable of carrying out the conversion into various kinds of resolution by using single bit map data in the digital TV. The image display device includes: a data processing part for executing bit map conversion, compression, restoration and format-conversion for text data; a memory for storing the bit map data obtained according to the bit map conversion and compression in the data processing part and image data inputted from an arbitrary receiving part, the receiving part receiving one of digital image data and analog image data; an image outputting part for reading the image data from the memory; and a display processing part for mixing the image data read from the image outputting part and the bit map data converted in format from the a data processing part. Therefore, the image display device according to the present invention can convert text data in such a manner as to correspond with various resolution, carry out the compression for bit map data, thereby reducing the memory space, and support text data of an HTML format, thereby providing the image with the text data of various shapes.

  5. Digital imaging and fabrication.

    PubMed

    Zandparsa, Roya

    2014-01-01

    Bioceramics have been adopted in dental restorations for implants, bridges, inlays, onlays, and all-ceramic crowns. Dental bioceramics include glass ceramics, reinforced porcelains, zirconias, aluminas, fiber-reinforced ceramic composites, and multilayered ceramic structures. The process of additive manufacturing is ideally suited to dentistry. Models are designed using data from a computed tomography scan or magnetic resonance imaging. Since its development in 2001, direct ceramic machining of presintered yttria tetragonal zirconia polycrystal has become increasingly popular in dentistry. There are wide variety commercially available cements for luting all-ceramic restorations. However, resin cements have lower solubility and better aesthetic characteristics. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. Aquarius Digital Processing Unit

    NASA Technical Reports Server (NTRS)

    Forgione, Joshua; Winkert, George; Dobson, Norman

    2009-01-01

    Three documents provide information on a digital processing unit (DPU) for the planned Aquarius mission, in which a radiometer aboard a spacecraft orbiting Earth is to measure radiometric temperatures from which data on sea-surface salinity are to be deduced. The DPU is the interface between the radiometer and an instrument-command-and-data system aboard the spacecraft. The DPU cycles the radiometer through a programmable sequence of states, collects and processes all radiometric data, and collects all housekeeping data pertaining to operation of the radiometer. The documents summarize the DPU design, with emphasis on innovative aspects that include mainly the following: a) In the radiometer and the DPU, conversion from analog voltages to digital data is effected by means of asynchronous voltage-to-frequency converters in combination with a frequency-measurement scheme implemented in field-programmable gate arrays (FPGAs). b) A scheme to compensate for aging and changes in the temperature of the DPU in order to provide an overall temperature-measurement accuracy within 0.01 K includes a high-precision, inexpensive DC temperature measurement scheme and a drift-compensation scheme that was used on the Cassini radar system. c) An interface among multiple FPGAs in the DPU guarantees setup and hold times.

  7. Digital processing of Mariner 9 television data.

    NASA Technical Reports Server (NTRS)

    Green, W. B.; Seidman, J. B.

    1973-01-01

    The digital image processing performed by the Image Processing Laboratory (IPL) at JPL in support of the Mariner 9 mission is summarized. The support is divided into the general categories of image decalibration (the removal of photometric and geometric distortions from returned imagery), computer cartographic projections in support of mapping activities, and adaptive experimenter support (flexible support to provide qualitative digital enhancements and quantitative data reduction of returned imagery). Among the tasks performed were the production of maximum discriminability versions of several hundred frames to support generation of a geodetic control net for Mars, and special enhancements supporting analysis of Phobos and Deimos images.

  8. Digital processing of Mariner 9 television data.

    NASA Technical Reports Server (NTRS)

    Green, W. B.; Seidman, J. B.

    1973-01-01

    The digital image processing performed by the Image Processing Laboratory (IPL) at JPL in support of the Mariner 9 mission is summarized. The support is divided into the general categories of image decalibration (the removal of photometric and geometric distortions from returned imagery), computer cartographic projections in support of mapping activities, and adaptive experimenter support (flexible support to provide qualitative digital enhancements and quantitative data reduction of returned imagery). Among the tasks performed were the production of maximum discriminability versions of several hundred frames to support generation of a geodetic control net for Mars, and special enhancements supporting analysis of Phobos and Deimos images.

  9. GEMAS: Spatial pattern analysis of Ni by using digital image processing techniques on European agricultural soil data

    NASA Astrophysics Data System (ADS)

    Jordan, Gyozo; Petrik, Attila; De Vivo, Benedetto; Albanese, Stefano; Demetriades, Alecos; Sadeghi, Martiya

    2017-04-01

    Several studies have investigated the spatial distribution of chemical elements in topsoil (0-20 cm) within the framework of the EuroGeoSurveys Geochemistry Expert Group's 'Geochemical Mapping of Agricultural and Grazing Land Soil' project . Most of these studies used geostatistical analyses and interpolated concentration maps, Exploratory and Compositional Data and Analysis to identify anomalous patterns. The objective of our investigation is to demonstrate the use of digital image processing techniques for reproducible spatial pattern recognition and quantitative spatial feature characterisation. A single element (Ni) concentration in agricultural topsoil is used to perform the detailed spatial analysis, and to relate these features to possible underlying processes. In this study, simple univariate statistical methods were implemented first, and Tukey's inner-fence criterion was used to delineate statistical outliers. The linear and triangular irregular network (TIN) interpolation was used on the outlier-free Ni data points, which was resampled to a 10*10 km grid. Successive moving average smoothing was applied to generalise the TIN model and to suppress small- and at the same time enhance significant large-scale features of Nickel concentration spatial distribution patterns in European topsoil. The TIN map smoothed with a moving average filter revealed the spatial trends and patterns without losing much detail, and it was used as the input into digital image processing, such as local maxima and minima determination, digital cross sections, gradient magnitude and gradient direction calculation, second derivative profile curvature calculation, edge detection, local variability assessment, lineament density and directional variogram analyses. The detailed image processing analysis revealed several NE-SW, E-W and NW-SE oriented elongated features, which coincide with different spatial parameter classes and alignment with local maxima and minima. The NE-SW oriented

  10. The APL image processing laboratory

    NASA Technical Reports Server (NTRS)

    Jenkins, J. O.; Randolph, J. P.; Tilley, D. G.; Waters, C. A.

    1984-01-01

    The present and proposed capabilities of the Central Image Processing Laboratory, which provides a powerful resource for the advancement of programs in missile technology, space science, oceanography, and biomedical image analysis, are discussed. The use of image digitizing, digital image processing, and digital image output permits a variety of functional capabilities, including: enhancement, pseudocolor, convolution, computer output microfilm, presentation graphics, animations, transforms, geometric corrections, and feature extractions. The hardware and software of the Image Processing Laboratory, consisting of digitizing and processing equipment, software packages, and display equipment, is described. Attention is given to applications for imaging systems, map geometric correction, raster movie display of Seasat ocean data, Seasat and Skylab scenes of Nantucket Island, Space Shuttle imaging radar, differential radiography, and a computerized tomographic scan of the brain.

  11. The APL image processing laboratory

    NASA Technical Reports Server (NTRS)

    Jenkins, J. O.; Randolph, J. P.; Tilley, D. G.; Waters, C. A.

    1984-01-01

    The present and proposed capabilities of the Central Image Processing Laboratory, which provides a powerful resource for the advancement of programs in missile technology, space science, oceanography, and biomedical image analysis, are discussed. The use of image digitizing, digital image processing, and digital image output permits a variety of functional capabilities, including: enhancement, pseudocolor, convolution, computer output microfilm, presentation graphics, animations, transforms, geometric corrections, and feature extractions. The hardware and software of the Image Processing Laboratory, consisting of digitizing and processing equipment, software packages, and display equipment, is described. Attention is given to applications for imaging systems, map geometric correction, raster movie display of Seasat ocean data, Seasat and Skylab scenes of Nantucket Island, Space Shuttle imaging radar, differential radiography, and a computerized tomographic scan of the brain.

  12. Image Processing

    NASA Technical Reports Server (NTRS)

    1993-01-01

    Electronic Imagery, Inc.'s ImageScale Plus software, developed through a Small Business Innovation Research (SBIR) contract with Kennedy Space Flight Center for use on space shuttle Orbiter in 1991, enables astronauts to conduct image processing, prepare electronic still camera images in orbit, display them and downlink images to ground based scientists for evaluation. Electronic Imagery, Inc.'s ImageCount, a spin-off product of ImageScale Plus, is used to count trees in Florida orange groves. Other applications include x-ray and MRI imagery, textile designs and special effects for movies. As of 1/28/98, company could not be located, therefore contact/product information is no longer valid.

  13. Digital Processing of Passive Ka-Band Microwave Images for Sea-Ice Classification

    DTIC Science & Technology

    1984-05-01

    Development Activity »’ NSTL, Mississippi 39529 Foreword Field trials of an airborne passive-microwave imaging system (MICRAD) in April 1976 demonstrated...Ross Williams). Engineering field tests of the KRMS were completed in December 1982. First use of the KRMS in support of an Arctic research...brightness temperature 6 Numerical approach to image classification 11 Field data 13 Histograms 14 Training regions 14 Open water 14 Old ice 15 First

  14. Digitizing And Interfacing Of Nondigital Images

    NASA Astrophysics Data System (ADS)

    Baily, Norman A.

    1982-01-01

    In discussing analog or non-digital images it is important to recognize that all images are generated by an interaction between quanta (either light, x or gamma rays, etc.) or particulate radiations, and a substance capable of responding to the interaction of these rays and that substance in such a way that an image can be generated. The intensity of the primary radiation and its spatial variation will then reflect the object being imaged. Therefore, the real difference between a digitized and an analog image lies in the method of recording this data. Many of the systems classified as digital make use of first-stage analog devices from which information is extracted and then transformed to a digitized format. In this paper we will discuss images which have not undergone such a transformation and which have been stored in analog form by an analog storage device. Such storage devices are usually photographic film, video disk, or video tape. It is from these analog storage media that subsequent digitization and/or processing by computer takes place. The choice of the methods of recording and digitization can greatly influence the signal to noise level and therefore the precision and accuracy of the computed results whether expressed as an image or in terms of numbers. Commonly used are video cameras, laser scanners, and photo-electronic scanners. The signal to noise level capabilities of these digitization modalities also influence both spatial and gray level resolutions achievable. In the case of radiological imaging most applications utilizing digitization have involved the use of video. The use of video for such applications has been reviewed recently.' In this paper we shall restrict our discussion to this modality.

  15. Digital x-ray imager

    SciTech Connect

    1998-06-18

    The global objective of this cooperation was to lower the cost and improve the quality of breast health care in the United States. We planned to achieve it by designing a very high performance digital radiography unit for breast surgical specimen radiography in the operating room. These technical goals needed to be achieved at reasonable manufacturing costs to enable MedOptics to achieve high market penetration at a profit. Responsibility for overall project execution rested with MedOptics. MedOptics fabricated and demonstrated hardware, and selected components and handled the overall integration. After completion of this CRADA, MedOptics worked with collaborators to demonstrate clinical performance and utility. Finally, the company marketed the device. LLNL convened a multi-directorate expert panel for an intensive review of MedOptics point design. A written brief of panel conclusions and recommendations was prepared. In addition, LLNL was responsible for: computationally simulating the effects of varying source voltage and filtering (predicting the required dynamic range for the detector); evaluating CsI:Tl, CdWO4 and scintillating glass as image converters; recommending image enhancement algorithms. The LLNL modeling results guided the design and experimental elements of the project. The Laboratory's unique array of sources and detectors was employed to resolve specific technical questions. Our image processing expertise was applied to the selection of enhancement tools for image display.

  16. Computer image processing and recognition

    NASA Technical Reports Server (NTRS)

    Hall, E. L.

    1979-01-01

    A systematic introduction to the concepts and techniques of computer image processing and recognition is presented. Consideration is given to such topics as image formation and perception; computer representation of images; image enhancement and restoration; reconstruction from projections; digital television, encoding, and data compression; scene understanding; scene matching and recognition; and processing techniques for linear systems.

  17. Computer image processing and recognition

    NASA Technical Reports Server (NTRS)

    Hall, E. L.

    1979-01-01

    A systematic introduction to the concepts and techniques of computer image processing and recognition is presented. Consideration is given to such topics as image formation and perception; computer representation of images; image enhancement and restoration; reconstruction from projections; digital television, encoding, and data compression; scene understanding; scene matching and recognition; and processing techniques for linear systems.

  18. Image Processing System

    NASA Technical Reports Server (NTRS)

    1986-01-01

    Mallinckrodt Institute of Radiology (MIR) is using a digital image processing system which employs NASA-developed technology. MIR's computer system is the largest radiology system in the world. It is used in diagnostic imaging. Blood vessels are injected with x-ray dye, and the images which are produced indicate whether arteries are hardened or blocked. A computer program developed by Jet Propulsion Laboratory known as Mini-VICAR/IBIS was supplied to MIR by COSMIC. The program provides the basis for developing the computer imaging routines for data processing, contrast enhancement and picture display.

  19. Digital enhancement of flow field images

    NASA Technical Reports Server (NTRS)

    Kudlinski, Robert A.; Park, Stephen K.

    1988-01-01

    Most photographs of experimentally generated fluid flow fields have inherently poor photographic quality, specifically low contrast. Thus, there is a need to establish a process for quickly and accurately enhancing these photographs to provide improved versions for physical interpretation, analysis, and publication. A sequence of digital image processing techniques which have been demonstrated to effectively enhance such photographs is described.

  20. Digital processing techniques and film density calibration for printing image data

    USGS Publications Warehouse

    Chavez, Pat S.; McSweeney, Joseph A.; Binnie, Douglas R.

    1987-01-01

    Satellite image data that cover a wide range of environments are being used to make prints that represent a map type product. If a wide distribution of these products is desired, they are printed using lithographic rather than photographic procedures to reduce the cost per print. Problems are encountered in the photo lab if the film products to be used for lithographic printing have the same density range and density curve characteristics as the film used for photographic printing. A method is presented that keeps the film densities within the 1.1 range required for lithographic printing, but generates film products with contrast similar to that in photographic film for the majority of data (80 percent). Also, spatial filters can be used to enhance local detail in dark and bright regions, as well as to sharpen the final image product using edge enhancement techniques.

  1. [Digitalization of histological images as a method of quantifying the demyelinating process].

    PubMed

    Stojiljković, G; Tasić, M; Budakov, B

    1996-01-01

    The basic aim of this paper was to check the hypothesis whether after head trauma the brain tissue looses myelinic membrane which surrounds the axon, and if this possibly established loss can be quantified, that is if it is possible to determine the degree of disintegration. One of the aims was to examine this method itself. The gathered results show that both the hypothesis and the aims were justified. It has been established that the diffuse axonal lesion in the examined samples reflects in a loss of axon's myelinic membrane. The loss was 50% greater in the test group in regard to the control group. To digitalize histologic pictures we have used Laser Scanner Densitometry Station and software by Biomed. In regard to medical jurisprudence, the laser scanner densitometry offers more relevant data in cases apparently unclear and in sudden deaths after head injuries. Application of this method and further investigations will be directed to further attempts to clear up connections between the mechanism of injury and degree of biologic response of the brain tissue.

  2. FBI compression standard for digitized fingerprint images

    NASA Astrophysics Data System (ADS)

    Brislawn, Christopher M.; Bradley, Jonathan N.; Onyshczak, Remigius J.; Hopper, Thomas

    1996-11-01

    The FBI has formulated national standards for digitization and compression of gray-scale fingerprint images. The compression algorithm for the digitized images is based on adaptive uniform scalar quantization of a discrete wavelet transform subband decomposition, a technique referred to as the wavelet/scalar quantization method. The algorithm produces archival-quality images at compression ratios of around 15 to 1 and will allow the current database of paper fingerprint cards to be replaced by digital imagery. A compliance testing program is also being implemented to ensure high standards of image quality and interchangeability of data between different implementations. We will review the current status of the FBI standard, including the compliance testing process and the details of the first-generation encoder.

  3. Phase-shifting of correlation fringes created by image processing as an alternative to improve digital shearography

    NASA Astrophysics Data System (ADS)

    Braga, Roberto A.; González-Peña, Rolando J.; Marcon, Marlon; Magalhães, Ricardo R.; Paiva-Almeida, Thiago; Santos, Igor V. A.; Martins, Moisés

    2016-12-01

    The adoption of digital speckle pattern shearing interferometry, or speckle shearography, is well known in many areas when one needs to measure micro-displacements in-plane and out of the plane in biological and non-biological objects; it is based on the Michelson's Interferometer with the use of a piezoelectric transducer (PZT) in order to provide the phase-shift of the fringes and then to improve the quality of the final image. The creation of the shifting images using a PZT, despite its widespread use, has some drawbacks or limitations, such as the cost of the apparatus, the difficulties in applying the same displacement in the mirror repeated times, and when the phase-shift cannot be used in dynamic object measurement. The aim of this work was to create digitally phase-shift images avoiding the mechanical adjustments of the PZT, testing them with the digital shearography method. The methodology was tested using a well-known object, a cantilever beam of aluminium under deformation. The results documented the ability to create the deformation map and curves with reliability and sensitivity, reducing the cost, and improving the robustness and also the accessibility of digital speckle pattern shearing interferometry.

  4. Image-Processing Program

    NASA Technical Reports Server (NTRS)

    Roth, D. J.; Hull, D. R.

    1994-01-01

    IMAGEP manipulates digital image data to effect various processing, analysis, and enhancement functions. It is keyboard-driven program organized into nine subroutines. Within subroutines are sub-subroutines also selected via keyboard. Algorithm has possible scientific, industrial, and biomedical applications in study of flows in materials, analysis of steels and ores, and pathology, respectively.

  5. Image-Processing Program

    NASA Technical Reports Server (NTRS)

    Roth, D. J.; Hull, D. R.

    1994-01-01

    IMAGEP manipulates digital image data to effect various processing, analysis, and enhancement functions. It is keyboard-driven program organized into nine subroutines. Within subroutines are sub-subroutines also selected via keyboard. Algorithm has possible scientific, industrial, and biomedical applications in study of flows in materials, analysis of steels and ores, and pathology, respectively.

  6. Image Processing

    DTIC Science & Technology

    1999-03-01

    blurs the processed image. Blurring is the primary limitation of low-pass filtering. Figure (10) shows a photo of the famous Taj -Hahal, one of the...Original Histo(p"am FILENAME.APP=41 06FG 1 O.PSD APPLICATION: ADOBE PHOTOSHOP VERSION 4.0 Figure (10) Photo ofTaj- Mahal with arbitrarily noise

  7. Application of digital image processing techniques and information systems to water quality monitoring of Lake Tahoe

    NASA Technical Reports Server (NTRS)

    Smith, A. Y.; Blackwell, R. J.

    1981-01-01

    The Tahoe basin occupies over 500 square miles of territory located in a graben straddling the boundary between California and Nevada. Lake Tahoe contains 126 million acre-feet of water. Since the 1950's the basin has experienced an ever increasing demand for land development at the expense of the natural watershed. Discharge of sediment to the lake has greatly increased owing to accelerated human interference, and alterations to the natural drainage patterns are evident in some areas. In connection with an investigation of the utility of a comprehensive system that takes into account the causes as well as the effects of lake eutrophication, it has been attempted to construct an integrated and workable data base, comprised of currently available data sources for the Lake Tahoe region. Attention is given to the image based information system (IBIS), the construction of the Lake Tahoe basin data base, and the application of the IBIS concept to the Lake Tahoe basin.

  8. Application of digital image processing techniques and information systems to water quality monitoring of Lake Tahoe

    NASA Technical Reports Server (NTRS)

    Smith, A. Y.; Blackwell, R. J.

    1981-01-01

    The Tahoe basin occupies over 500 square miles of territory located in a graben straddling the boundary between California and Nevada. Lake Tahoe contains 126 million acre-feet of water. Since the 1950's the basin has experienced an ever increasing demand for land development at the expense of the natural watershed. Discharge of sediment to the lake has greatly increased owing to accelerated human interference, and alterations to the natural drainage patterns are evident in some areas. In connection with an investigation of the utility of a comprehensive system that takes into account the causes as well as the effects of lake eutrophication, it has been attempted to construct an integrated and workable data base, comprised of currently available data sources for the Lake Tahoe region. Attention is given to the image based information system (IBIS), the construction of the Lake Tahoe basin data base, and the application of the IBIS concept to the Lake Tahoe basin.

  9. How to Implement an E-Learning Curriculum to Streamline Teaching Digital Image Processing

    ERIC Educational Resources Information Center

    Király, Sándor

    2016-01-01

    In the field of teaching, one of the interesting subjects is the research of the fact which didactic methods are good for learning the current curriculum for the students who show a wide range of age, interest, chosen courses, previous studies and motivation. This article introduces the facilities that support the learning process: the…

  10. Digital imaging and video: principles and applications.

    PubMed

    Rosen, Andrew L; Hausman, Michael

    2003-01-01

    Digital imaging has provided orthopaedic surgeons with new, powerful tools that offer a multitude of applications. Already integral to several common medical devices, digital images can be used for case documentation and presentation as well as for diagnostic and surgical patient care information. Educational presentation has been transformed by the use of computers and digital projectors. Understanding the basic foundations of digital imaging technology is important for effectively creating digital images, videos, and presentations.

  11. Web platform using digital image processing and geographic information system tools: a Brazilian case study on dengue.

    PubMed

    Brasil, Lourdes M; Gomes, Marília M F; Miosso, Cristiano J; da Silva, Marlete M; Amvame-Nze, Georges D

    2015-07-16

    Dengue fever is endemic in Asia, the Americas, the East of the Mediterranean and the Western Pacific. According to the World Health Organization, it is one of the diseases of greatest impact on health, affecting millions of people each year worldwide. A fast detection of increases in populations of the transmitting vector, the Aedes aegypti mosquito, is essential to avoid dengue outbreaks. Unfortunately, in several countries, such as Brazil, the current methods for detecting populations changes and disseminating this information are too slow to allow efficient allocation of resources to fight outbreaks. To reduce the delay in providing the information regarding A. aegypti population changes, we propose, develop, and evaluate a system for counting the eggs found in special traps and to provide the collected data using a web structure with geographical location resources. One of the most useful tools for the detection and surveillance of arthropods is the ovitrap, a special trap built to collect the mosquito eggs. This allows for an egg counting process, which is still usually performed manually, in countries such as Brazil. We implement and evaluate a novel system for automatically counting the eggs found in the ovitraps' cardboards. The system we propose is based on digital image processing (DIP) techniques, as well as a Web based Semi-Automatic Counting System (SCSA-WEB). All data collected are geographically referenced in a geographic information system (GIS) and made available on a Web platform. The work was developed in Gama's administrative region, in Brasília/Brazil, with the aid of the Environmental Surveillance Directory (DIVAL-Gama) and Brasília's Board of Health (SSDF), in partnership with the University of Brasília (UnB). The system was built based on a field survey carried out during three months and provided by health professionals. These professionals provided 84 cardboards from 84 ovitraps, sized 15 × 5 cm. In developing the system, we conducted

  12. High-speed four-color infrared digital imaging for studying in-cylinder processes in a DI diesel engine

    NASA Astrophysics Data System (ADS)

    Rhee, K. T.

    1995-07-01

    The study was to investigate in-cylinder events of a direct injection-type diesel engine by using a new high-speed infrared (IR) digital imaging systems for obtaining information that was difficult to achieve by the conventional devices. For this, a new high-speed dual-spectra infrared digital imaging system was developed to simultaneously capture two geometrically identical (in respective spectral) sets of IR images having discrete digital information in a (64x64) matrix at rates as high as over 1,800 frames/sec each with exposure period as short as 20 micron sec. At the same time, a new advanced four-color W imaging system was constructed. The first two sets of spectral data were the radiation from water vapor emission bands to compute the distributions of temperature and specie in the gaseous mixture and the remaining two sets of data were to find the instantaneous temperature distribution over the cylinder surface. More than eight reviewed publications have been produced to report many new findings including: Distributions of Water Vapor and Temperature in a Flame; End Gas Images Prior to Onset of Knock; Effect of MTBE on Diesel Combustion; Impact of Oxygen Enrichment on In-cylinder Reactions; Spectral IR Images of Spray Plume; Residual Gas Distribution; Preflame Reactions in Diesel Combustion; Preflame Reactions in the End Gas of an SI Engine; Postflame Oxidation; and Liquid Fuel Layers during Combustion in an SI Engine. In addition, some computational analysis of diesel combustion was performed using KIVA-II program in order to compare results from the prediction and the measurements made using the new IR imaging diagnostic tool.

  13. ASTER digital image processing for geological mapping: Examples from Neoproterozoic Allaqi-Heiani Suture, Egypt

    NASA Astrophysics Data System (ADS)

    Ren, Dianwei

    This dissertation constitutes three manuscripts summarizing efforts in developing effective algorithms for the analysis of the Advanced Space-borne Thermal Emission and Reflection Radiometer (ASTER) data for geological mapping using the Neoproterozoic Allagi-Heiani Suture (AHS) in southern Egypt as a test site. The first manuscript presents statistical approach for the selection of ASTER bands to be used for Red-Green-Blue (RGB) color combination images. The Optimum Index Factor (OIF) and determinants techniques are proposed to rank all possible ASTER RGB color combinations for the western part of AHS. ASTER has three subsystems including Visible and Near Infra-Red (VNIR), Short Wave Infra-Red (SWIR), and Thermal Infra-Red (TIR). Hence, ASTER bands can be used in seven Electromagnetic Spectrum (EMS) regions combinations. These are VNIR only, SWIR only, TIR only, VNIR+SWIR, VNIR+TIR, SWIR+TIR, and VNIR+SWIR+TIR. The OIF and determinants results agree in four of the seven EMS regions combinations (VNIR only, SWIR only, TIR only, and VNIR+SWIR), but differ in three (VNIR+TIR, SWIR+TIR, and VNIR+SWIR+TIR). The second manuscript outlines an effective algorithm to spectrally separate ophiolite components in AHS and use these as markers to trace the continuity of geological structures. Principal component analysis (PCA), Fast Fourier Transform (FFT), and Redundant Wavelet Transform (RWT) are used to identify ophiolite components as well as Neoproterozoic ductile structures to trace along-strike continuation in AHS. This work helps trace structures along AHS and reveals structures that have not been identified before. Nappes identified in the west are traced into the central part of the suture allowing for subsequent modification by younger structures. The third manuscript outlines a methodology to quantitatively evaluate ASTER band-ratios that can be effectively used for thematic classification aimed at separating distinctive lithologies in AHS. The Within

  14. The Process of Digitizing of Old Globe

    NASA Astrophysics Data System (ADS)

    Ambrožová, K.; Havrlanta, J.; Talich, M.; Böhm, O.

    2016-06-01

    This paper describes the process of digitalization of old globes that brings with it the possibility to use globes in their digital form. Created digital models are available to the general public through modern technology in the Internet network. This gives an opportunity to study old globes located in various historical collections, and prevent damage of the originals. Another benefit of digitization is also a possibility of comparing different models both among themselves and with current map data by increasing the transparency of individual layers. Digitization is carried out using special device that allows digitizing globes with a diameter ranging from 5 cm to 120 cm. This device can be easily disassembled, and it is fully mobile therefore the globes can be digitized in the place of its storage. Image data of globe surface are acquired by digital camera firmly fastened to the device. Acquired image data are then georeferenced by using a method of complex adjustment. The last step of digitization is publication of the final models that is realized by two ways. The first option is in the form of 3D model through JavaScript library Cesium or Google Earth plug-in in the Web browser. The second option is as a georeferenced map using Tile Map Service.

  15. Autofluorescence endoscopy with "real-time" digital image processing in differential diagnostics of selected benign and malignant lesions in the oesophagus.

    PubMed

    Sieroń-Stołtny, Karolina; Kwiatek, Sebastian; Latos, Wojciech; Kawczyk-Krupka, Aleksandra; Cieślar, Grzegorz; Stanek, Agata; Ziaja, Damian; Bugaj, Andrzej M; Sieroń, Aleksander

    2012-03-01

    Oesophageal papilloma and Barrett's oesophagus are benign lesions known as risk factors of carcinoma in the oesophagus. Therefore, it is important to diagnose these early changes before neoplastic transformation. Autofluorescence endoscopy is a fast and non-invasive method of imaging of tissues based on the natural fluorescence of endogenous fluorophores. The aim of this study was to prove the diagnostic utility of autofluorescence endoscopy with digital image processing in histological diagnosis of endoscopic findings in the upper digestive tract, primarily in the imaging of oesophageal papilloma. During the retrospective analysis of about 200 endoscopic procedures in the upper digestive tract, 67 cases of benign, precancerous or cancerous changes were found. White light endoscopy (WLE) image, single-channel (red or green) autofluorescence images, as well as green and red fluorescence intensities in two modal fluorescence image and red-to-green (R/G) ratio (Numerical Colour Value, NCV) were correlated with histopathologic results. The NCV analysis in autofluorescence imaging (AFI) showed increased R/G ratio in cancerous changes in 96% vs. 85% in WLE. Simultaneous analysis with digital image processing allowed us to diagnose suspicious tissue as cancerous in all of cases. Barrett's metaplasia was confirmed in 90% vs. 79% (AFI vs. WLE), and 98% in imaging with digital image processing. In benign lesions, WLE allowed us to exclude tissue as malignant in 85%. Using autofluorescence endoscopy R/G ratio was increased in only 10% of benign changes causing the picture to be interpreted as suspicious, but when both methods were used together, 97.5% were cases excluded as malignancies. Mean R/G ratios were estimated to be 2.5 in cancers, 1.25 in Barrett's metaplasia and 0.75 in benign changes and were statistically significant (p=0.04). Autofluorescence imaging is a sensitive method to diagnose precancerous and cancerous early stages of the diseases located in oesophagus

  16. Estimation of breast percent density in raw and processed full field digital mammography images via adaptive fuzzy c-means clustering and support vector machine segmentation.

    PubMed

    Keller, Brad M; Nathan, Diane L; Wang, Yan; Zheng, Yuanjie; Gee, James C; Conant, Emily F; Kontos, Despina

    2012-08-01

    The amount of fibroglandular tissue content in the breast as estimated mammographically, commonly referred to as breast percent density (PD%), is one of the most significant risk factors for developing breast cancer. Approaches to quantify breast density commonly focus on either semiautomated methods or visual assessment, both of which are highly subjective. Furthermore, most studies published to date investigating computer-aided assessment of breast PD% have been performed using digitized screen-film mammograms, while digital mammography is increasingly replacing screen-film mammography in breast cancer screening protocols. Digital mammography imaging generates two types of images for analysis, raw (i.e., "FOR PROCESSING") and vendor postprocessed (i.e., "FOR PRESENTATION"), of which postprocessed images are commonly used in clinical practice. Development of an algorithm which effectively estimates breast PD% in both raw and postprocessed digital mammography images would be beneficial in terms of direct clinical application and retrospective analysis. This work proposes a new algorithm for fully automated quantification of breast PD% based on adaptive multiclass fuzzy c-means (FCM) clustering and support vector machine (SVM) classification, optimized for the imaging characteristics of both raw and processed digital mammography images as well as for individual patient and image characteristics. Our algorithm first delineates the breast region within the mammogram via an automated thresholding scheme to identify background air followed by a straight line Hough transform to extract the pectoral muscle region. The algorithm then applies adaptive FCM clustering based on an optimal number of clusters derived from image properties of the specific mammogram to subdivide the breast into regions of similar gray-level intensity. Finally, a SVM classifier is trained to identify which clusters within the breast tissue are likely fibroglandular, which are then aggregated into a

  17. Estimation of breast percent density in raw and processed full field digital mammography images via adaptive fuzzy c-means clustering and support vector machine segmentation

    SciTech Connect

    Keller, Brad M.; Nathan, Diane L.; Wang Yan; Zheng Yuanjie; Gee, James C.; Conant, Emily F.; Kontos, Despina

    2012-08-15

    Purpose: The amount of fibroglandular tissue content in the breast as estimated mammographically, commonly referred to as breast percent density (PD%), is one of the most significant risk factors for developing breast cancer. Approaches to quantify breast density commonly focus on either semiautomated methods or visual assessment, both of which are highly subjective. Furthermore, most studies published to date investigating computer-aided assessment of breast PD% have been performed using digitized screen-film mammograms, while digital mammography is increasingly replacing screen-film mammography in breast cancer screening protocols. Digital mammography imaging generates two types of images for analysis, raw (i.e., 'FOR PROCESSING') and vendor postprocessed (i.e., 'FOR PRESENTATION'), of which postprocessed images are commonly used in clinical practice. Development of an algorithm which effectively estimates breast PD% in both raw and postprocessed digital mammography images would be beneficial in terms of direct clinical application and retrospective analysis. Methods: This work proposes a new algorithm for fully automated quantification of breast PD% based on adaptive multiclass fuzzy c-means (FCM) clustering and support vector machine (SVM) classification, optimized for the imaging characteristics of both raw and processed digital mammography images as well as for individual patient and image characteristics. Our algorithm first delineates the breast region within the mammogram via an automated thresholding scheme to identify background air followed by a straight line Hough transform to extract the pectoral muscle region. The algorithm then applies adaptive FCM clustering based on an optimal number of clusters derived from image properties of the specific mammogram to subdivide the breast into regions of similar gray-level intensity. Finally, a SVM classifier is trained to identify which clusters within the breast tissue are likely fibroglandular, which are then

  18. Digital mammography, cancer screening: Factors important for image compression

    NASA Technical Reports Server (NTRS)

    Clarke, Laurence P.; Blaine, G. James; Doi, Kunio; Yaffe, Martin J.; Shtern, Faina; Brown, G. Stephen; Winfield, Daniel L.; Kallergi, Maria

    1993-01-01

    The use of digital mammography for breast cancer screening poses several novel problems such as development of digital sensors, computer assisted diagnosis (CAD) methods for image noise suppression, enhancement, and pattern recognition, compression algorithms for image storage, transmission, and remote diagnosis. X-ray digital mammography using novel direct digital detection schemes or film digitizers results in large data sets and, therefore, image compression methods will play a significant role in the image processing and analysis by CAD techniques. In view of the extensive compression required, the relative merit of 'virtually lossless' versus lossy methods should be determined. A brief overview is presented here of the developments of digital sensors, CAD, and compression methods currently proposed and tested for mammography. The objective of the NCI/NASA Working Group on Digital Mammography is to stimulate the interest of the image processing and compression scientific community for this medical application and identify possible dual use technologies within the NASA centers.

  19. The Apollo Digital Image Archive: Project Status

    NASA Astrophysics Data System (ADS)

    Paris, K. N.; Robinson, M. S.; Lawrence, S. J.; Danton, J.; Bowman-Cisneros, E.; Licht, A.; Close, W.; Ingram, R.

    2012-03-01

    Photographs acquired by the Apollo astronauts are currently being scanned at JSC and the files sent to ASU for the Apollo Digital Image Archive. The metric frames are nearing completion while the panoramic frames are in the process of being released.

  20. An experimental investigation on the surface water transport process over an airfoil by using a digital image projection technique

    NASA Astrophysics Data System (ADS)

    Zhang, Kai; Wei, Tian; Hu, Hui

    2015-09-01

    In the present study, an experimental investigation was conducted to characterize the transient behavior of the surface water film and rivulet flows driven by boundary layer airflows over a NACA0012 airfoil in order to elucidate underlying physics of the important micro-physical processes pertinent to aircraft icing phenomena. A digital image projection (DIP) technique was developed to quantitatively measure the film thickness distribution of the surface water film/rivulet flows over the airfoil at different test conditions. The time-resolved DIP measurements reveal that micro-sized water droplets carried by the oncoming airflow impinged onto the airfoil surface, mainly in the region near the airfoil leading edge. After impingement, the water droplets formed thin water film that runs back over the airfoil surface, driven by the boundary layer airflow. As the water film advanced downstream, the contact line was found to bugle locally and developed into isolated water rivulets further downstream. The front lobes of the rivulets quickly advanced along the airfoil and then shed from the airfoil trailing edge, resulting in isolated water transport channels over the airfoil surface. The water channels were responsible for transporting the water mass impinging at the airfoil leading edge. Additionally, the transition location of the surface water transport process from film flows to rivulet flows was found to occur further upstream with increasing velocity of the oncoming airflow. The thickness of the water film/rivulet flows was found to increase monotonically with the increasing distance away from the airfoil leading edge. The runback velocity of the water rivulets was found to increase rapidly with the increasing airflow velocity, while the rivulet width and the gap between the neighboring rivulets decreased as the airflow velocity increased.

  1. The Heinz Electronic Library Interactive Online System (HELIOS): Building a Digital Archive Using Imaging, OCR, and Natural Language Processing Technologies.

    ERIC Educational Resources Information Center

    Galloway, Edward A.; Michalek, Gabrielle V.

    1995-01-01

    Discusses the conversion project of the congressional papers of Senator John Heinz into digital format and the provision of electronic access to these papers by Carnegie Mellon University. Topics include collection background, project team structure, document processing, scanning, use of optical character recognition software, verification…

  2. APQ-102 imaging radar digital image quality study

    NASA Technical Reports Server (NTRS)

    Griffin, C. R.; Estes, J. M.

    1982-01-01

    A modified APQ-102 sidelooking radar collected synthetic aperture radar (SAR) data which was digitized and recorded on wideband magnetic tape. These tapes were then ground processed into computer compatible tapes (CCT's). The CCT's may then be processed into high resolution radar images by software on the CYBER computer.

  3. Digital Color Image Restoration

    DTIC Science & Technology

    1975-08-01

    color image recording system is derived and the equations representing the model and the equations of colorimetry are expressed in matrix form. Computer ... algorithms are derived which correct color errors introduced by imperfections in the color recording system. The sources of color error which are

  4. Image digitizer system for bubble chamber laser

    SciTech Connect

    Haggerty, H

    1986-12-08

    An IBM PC-based image digitizer system has been assembled to monitor the laser flash used for holography at the 15 foot bubble chamber. The hardware and the operating software are outlined. For an operational test of the system, an array of LEDs was flashed with a 10 microsecond pulse and the image was grabbed by one of the operating programs and processed. (LEW)

  5. Architectures and algorithms for digital image processing; Proceedings of the Meeting, Cannes, France, December 5, 6, 1985

    NASA Technical Reports Server (NTRS)

    Duff, Michael J. B. (Editor); Siegel, Howard J. (Editor); Corbett, Francis J. (Editor)

    1986-01-01

    The conference presents papers on the architectures, algorithms, and applications of image processing. Particular attention is given to a very large scale integration system for image reconstruction from projections, a prebuffer algorithm for instant display of volume data, and an adaptive image sequence filtering scheme based on motion detection. Papers are also presented on a simple, direct practical method of sensing local motion and analyzing local optical flow, image matching techniques, and an automated biological dosimetry system.

  6. [A new method for eliminating scatter components from a digital X-ray image by later processing].

    PubMed

    Kato, Hideki

    2006-09-20

    The anti-scatter grid is generally used as a way of eliminating scattered radiation from X-ray photographs. This does not change even if the detector system changes from an analogue system to a digital system such as the flat-panel detector. We developed a new method that uses software to eliminate scatter components from digital X-ray images taken without the use of an anti-scatter grid. With this software, scatter components are eliminated from the X-ray image according to primary-to-scatter ratios, which were calculated on the basis of an imaginary phantom constructed by the pixel value of the X-ray image and on the spectrum of irradiated X-rays. In a trial calculation using a simulation image, it was confirmed that scatter components are eliminated at a high rate that is generally constant on the whole, irrespective of the kind and presence of the inhomogeneous region. When using this technique, the amount of X-ray exposure to a patient can be substantially reduced compared with that of radiography using the anti-scatter grid. Subsequently, the patient dose can be reduced.

  7. Digital imaging access library

    NASA Astrophysics Data System (ADS)

    Cook, Jay F.; Hansen, Mark; Francoise, James J.; Leckie, Robert G.; Smith, Donald V.

    1994-05-01

    The ability to access a vast array of radiological and pathologic diagnoses through computer searches of local medical facility databases is a by-product of the continued development of filmless imaging systems. The Department of Defense (DoD) Medical Diagnostic Imaging Support initiative is expanding through the addition of on-line systems at several DoD health care facilities. Madigan Army Medical Center, as the initial site, will soon be 90% filmless, with over one million images archived. Multiple other DoD medical centers are under installation. The eventual goal is an interconnected network of PACS systems of DoD medical centers and their supported medical facilities throughout the United States. To access this potential pool of medical information requires a centralized database capable of acting as a diagnostic index system. The establishment of a multi-center film library index begins with an initial analysis of issues regarding data storage and access, indexing, cross-coding with pathological files, communication formats, cost sharing, and patient confidentiality. In initiating these first steps to developing this telecommunications library these issues and their implications are discussed. The final implementation of this system will facilitate markedly improved research and teaching capabilities in both radiological and pathological fields.

  8. Nanophotonic filters for digital imaging

    NASA Astrophysics Data System (ADS)

    Walls, Kirsty

    There has been an increasing demand for low cost, portable CMOS image sensors because of increased integration, and new applications in the automotive, mobile communication and medical industries, amongst others. Colour reproduction remains imperfect in conventional digital image sensors, due to the limitations of the dye-based filters. Further improvement is required if the full potential of digital imaging is to be realised. In alternative systems, where accurate colour reproduction is a priority, existing equipment is too bulky for anything but specialist use. In this work both these issues are addressed by exploiting nanophotonic techniques to create enhanced trichromatic filters, and multispectral filters, all of which can be fabricated on-chip, i.e. integrated into a conventional digital image sensor, to create compact, low cost, mass produceable imaging systems with accurate colour reproduction. The trichromatic filters are based on plasmonic structures. They exploit the excitation of surface plasmon resonances in arrays of subwavelength holes in metal films to filter light. The currently-known analytical expressions are inadequate for optimising all relevant parameters of a plasmonic structure. In order to obtain arbitrary filter characteristics, an automated design procedure was developed that integrated a genetic algorithm and 3D finite-difference time-domain tool. The optimisation procedure's efficacy is demonstrated by designing a set of plasmonic filters that replicate the CIE (1931) colour matching functions, which themselves mimic the human eye's daytime colour response.

  9. Theory of Digital Imaging from Orbital Synthetic Aperture Radar

    DTIC Science & Technology

    1983-11-01

    FROM ORBITAL SYNTHETIC APERTURE RADAR O by B. C. Barber SUMMARY Digital synthetic aperture radar ( SAR ) imaging techniques have pre- viously only been...reported in the literature in a fragmentary manner. This article presents a comprehensive review of the theory of digital SAR imaging from Earth...orbiting satellites. The digital SAR imaging process is explained, including a discussion of various aspects which are specific to satellite-borne SAR . A

  10. Tomographic particle-image velocimetry and thermography in Rayleigh-Bénard convection using suspended thermochromic liquid crystals and digital image processing

    NASA Astrophysics Data System (ADS)

    Ciofalo, M.; Signorino, M.; Simiano, M.

    2003-02-01

    Steady-state flow and temperature fields in shallow rectangular enclosures heated from below were visualized and quantitatively characterized by using glycerol as the working fluid and suspended thermochromic liquid crystals as tracers. Couples of photographs taken on 120 transparency film for two orthogonal sets of vertical plane sections were digitized by a 1,200-dpi flatbed scanner and split into HSL (hue-saturation-lightness) components by using commercial general-purpose image processing software. Two-dimensional velocity fields were obtained from the lightness component by a two-frame cross-correlation technique using a commercial particle-image velocimetry (PIV) package. Temperature fields were obtained from the hue component on the basis of an in situ calibration procedure, conducted under conditions of stable thermal stratification. Finally, 2D flow and temperature distributions were interpolated by a purpose-written Fortran program to give 3D flow and thermal fields in the enclosure. Results are presented here for the case of a 1:2:4 aspect ratio cavity at a Rayleigh number of ˜ 14,500, for which a complex 3D flow and temperature distribution was observed.

  11. Digital Imaging and Communications in Medicine

    NASA Astrophysics Data System (ADS)

    Onken, Michael; Eichelberg, Marco; Riesmeier, Jörg; Jensch, Peter

    Over the past 15 years Digital Imaging and Communications in Medicine (DICOM) has established itself as the international standard for medical image communication. Most medical imaging equipment uses DICOM network and media services to export image data, thus making this standard highly relevant for medical image processing. The first section of this chapter provides a basic introduction into DICOM with its more than 3,600 pages of technical documentation, followed by a section covering selected advanced topics of special interest for medical image processing. The introductory text familiarizes the reader with the standard's main concepts such as information objects and DICOM media and network services. The rendering pipeline for image display and the concept of DICOM conformance are also discussed. Specialized DICOM services such as advanced image display services that provide means for storing how an image was viewed ("Softcopy Presentation States") and how multiple images should be aligned on an output device ("Structured Display" and "Hanging Protocols") are described. We further describe DICOM's sophisticated approach ("Structured Reporting") for storing structured documents such as CAD information, which is then covered in more detail. Finally, the last section provides an insight into a newly developed DICOM service called "Application Hosting", which introduces a standardized plug-in architecture for image processing, thus permitting users to utilize cross-vendor image processing plug-ins in DICOM applications.

  12. A novel digital magnetic resonance imaging spectrometer.

    PubMed

    Liu, Zhengmin; Zhao, Cong; Zhou, Heqin; Feng, Huanqing

    2006-01-01

    Spectrometer is the essential part of magnetic resonance imaging (MRI) system. It controls the transmitting and receiving of signals. Many commercial spectrometers are now available. However, they are usually costly and complex. In this paper, a new digital spectrometer based on PCI extensions for instrumentation (PXI) architecture is presented. Radio frequency (RF) pulse is generated with the method of digital synthesis and its frequency and phase are continuously tunable. MR signal acquired by receiver coils is processed by digital quadrature detection and filtered to get the k-space data, which avoid the spectral distortion due to amplitude and phase errors between two channels of traditional detection. Compared to the conventional design, the presented spectrometer is built with general PXI platform and boards. This design works in a digital manner with features of low cost, high performance and accuracy. The experiments demonstrate its efficiency.

  13. A new application of digital image processing to investigate thin compressed films: The measurement of buckling propagation

    NASA Astrophysics Data System (ADS)

    Wang, S. B.; Fang, Y. Z.; Jia, H. K.; Li, L. A.; Wang, Z. Y.; Zhang, S. J.

    2010-11-01

    Thin films are used increasingly in technological applications involving microelectromechanical systems, optical reflectors, filters, dielectric stacks, and lithographic resists. However, although the mechanical properties of these submicrometer-thick films are paramount for their effective utilization, many issues remain unresolved to date on the measurement of such properties in thin-film systems. In this paper, an electromechanical device is designed to study the mechanical properties and stability of thin films using two piezoelectric translators. The buckling propagation of thin compressed titanium films deposited on organic glass substrates is investigated utilizing an optical microscope. The rigid-body displacement of the observation field, which is caused by external uniaxial compressive loading, is calculated by the digital image correlation method. Edge detection and filter are carried out to obtain binary images in which the edges of the buckle are obvious, and false noise is eliminated. Therefore, a series of binary images obtained under different loads contains the information on buckling propagation. Further, rigid-body displacement could be compensated for digitally, and the propagation of buckles could be singled out. The experimental results confirm the theoretical proposition that "subcritical" defects can be used to indicate the rigid-body displacement of a substrate. The same method can be used to investigate other problems associated with film buckling.

  14. Image database for digital hand atlas

    NASA Astrophysics Data System (ADS)

    Cao, Fei; Huang, H. K.; Pietka, Ewa; Gilsanz, Vicente; Dey, Partha S.; Gertych, Arkadiusz; Pospiech-Kurkowska, Sywia

    2003-05-01

    Bone age assessment is a procedure frequently performed in pediatric patients to evaluate their growth disorder. A commonly used method is atlas matching by a visual comparison of a hand radiograph with a small reference set of old Greulich-Pyle atlas. We have developed a new digital hand atlas with a large set of clinically normal hand images of diverse ethnic groups. In this paper, we will present our system design and implementation of the digital atlas database to support the computer-aided atlas matching for bone age assessment. The system consists of a hand atlas image database, a computer-aided diagnostic (CAD) software module for image processing and atlas matching, and a Web user interface. Users can use a Web browser to push DICOM images, directly or indirectly from PACS, to the CAD server for a bone age assessment. Quantitative features on the examined image, which reflect the skeletal maturity, are then extracted and compared with patterns from the atlas image database to assess the bone age. The digital atlas method built on a large image database and current Internet technology provides an alternative to supplement or replace the traditional one for a quantitative, accurate and cost-effective assessment of bone age.

  15. Digital Imaging of Ice Cores: Early Results

    NASA Astrophysics Data System (ADS)

    Hargreaves, G.; McGwire, K.; Taylor, K.; Alley, R. B.; Dupont, T. K.; Reusch, D. B.

    2005-12-01

    Ice core science addresses fundamental questions of human interest related to global warming, abrupt climate change, biogeochemical cycling and more, and directly informs policymakers. The National Ice Core Laboratory (NICL) in Denver, Colorado, is currently developing a high-resolution optical scanning system for laboratory curation in order to expand the accessibility of ice core data sets through creation of a digital archive of ice core images. Additional goals of this project include development of internet-based search and retrieval capabilities from this digital archive; development of a digital image analysis system specifically for ice core studies; integration of digital optical data with other dating methods and testing of the image processing tools in scientific investigations. By providing permanent online digital archives of core quality, it will allow improved selection of samples, and documentation of possible core-quality artifacts for all U.S. ice core scientists. This project will allow any researcher to examine the core in similar detail to the few investigators who were fortunate enough to observe it before modifications from sampling and storage. This re-examination can be done decades later by anyone at any location, which is not possible now because only the interpretation of the original observer is recorded. Integration of this digital optical examination into ice core analysis will speed discovery, allow collaborative interpretation, and enhance consistency of analysis to improve ice core dating, identification of melt layers, location of flow disturbances, and more. Here we report on the current status of, and latest results from, these development efforts, including examples of images from the GISP2 (Greenland Ice Sheet Project Two) ice core. Preliminary work on this core shows that the imaging system successfully and accurately captures numerous features readily recognized by (trained) human observers, such as layering from changes in

  16. Process simulation in digital camera system

    NASA Astrophysics Data System (ADS)

    Toadere, Florin

    2012-06-01

    The goal of this paper is to simulate the functionality of a digital camera system. The simulations cover the conversion from light to numerical signal and the color processing and rendering. We consider the image acquisition system to be linear shift invariant and axial. The light propagation is orthogonal to the system. We use a spectral image processing algorithm in order to simulate the radiometric properties of a digital camera. In the algorithm we take into consideration the transmittances of the: light source, lenses, filters and the quantum efficiency of a CMOS (complementary metal oxide semiconductor) sensor. The optical part is characterized by a multiple convolution between the different points spread functions of the optical components. We use a Cooke triplet, the aperture, the light fall off and the optical part of the CMOS sensor. The electrical part consists of the: Bayer sampling, interpolation, signal to noise ratio, dynamic range, analog to digital conversion and JPG compression. We reconstruct the noisy blurred image by blending different light exposed images in order to reduce the photon shot noise, also we filter the fixed pattern noise and we sharpen the image. Then we have the color processing blocks: white balancing, color correction, gamma correction, and conversion from XYZ color space to RGB color space. For the reproduction of color we use an OLED (organic light emitting diode) monitor. The analysis can be useful to assist students and engineers in image quality evaluation and imaging system design. Many other configurations of blocks can be used in our analysis.

  17. A tool for designing digital test objects for module performance evaluation in medical digital imaging.

    PubMed

    Kocsis, O; Costaridou, L; Efstathopoulos, E P; Lymberopoulos, D; Panayiotakis, G

    1999-01-01

    Currently, medical digital imaging systems are characterized by the introduction of additional modules such as digital display, image compression and image processing, as well as film printing and digitization. These additional modules require performance evaluation to ensure high image quality. A tool for designing computer-generated test objects applicable to performance evaluation of these modules is presented. The test objects can be directly used as digital images in the case of film printing, display, compression and image processing, or indirectly as images on film in the case of digitization. The performance evaluation approach is quality control protocol based. Digital test object design is user-driven according to specifications related to the requirements of the modules being tested. The available quality control parameters include input/output response curve, high contrast resolution, low contrast discrimination, noise, geometric distortion and field uniformity. The tool has been designed and implemented according to an object oriented approach in Visual C++ 5.0, and its user interface is based on the Microsoft Foundation Class Library version 4.2, which provides interface items such as windows, dialog boxes, lists, buttons, etc. The compatibility with DICOM 3.0 part 10 image formats specifications allows the integration of the tool in the existing software framework for medical digital imaging systems. The capability of the tool is demonstrated by direct use of the test objects in case of image processing, and indirect use of the test objects in case of film digitization.

  18. TM Digital Image Products for Applications

    NASA Technical Reports Server (NTRS)

    Barker, J. L.; Gunther, F. J.; Abrams, R. B.; Ball, D. L.

    1984-01-01

    LANDSAT-4 Thematic Mapper (TM) digital image products recorded onto computer compatible tapes (CCTs), which were available for internal research purposes prior to August, 1983, are reviewed. The SCROUNGE image processing system at Goddard Space Flight Centr generated in tape formats: (1) raw band-sequential data (CCT-BT), generally used for internal transportation of digital data from one ground processing system to another; (2) calibrated data (CCT-AT), useful for reseachers doing radiometric characterization; and (3) geometrically resampled data (CCT-PT), the final product. The formats represent different steps in the process of producing fully-corrected TM data. The CCT-BT images are re-sequenced from telemetry format to image format, but are uncorrected radiometrically and geometrically. The CCT-AT images had data from two faulty data channels replaced and all data radiometrically calibrated. The CCT-PT images were resampled by cubic convolution procedures to provide a geometrically corrected image using satellite ephemeris and altitude data and scan-mirror correction data. The final product, the CCT-PT, is the one to which all of the radiometric and geometric corrections were applied.

  19. Imaging spectroscopy with digital micromirrors

    NASA Astrophysics Data System (ADS)

    Kearney, Kevin J.; Corio, Mark A.; Ninkov, Zoran

    2000-05-01

    The availability of optical MEMS (Micro-Electro-Mechanical Systems) is promising to revolutionize optical instrument design. We are developing a multiobject imaging spectrometer based on a commercially available optical MEMS--the Texas Instrument's Digital Micromirror Device (DMD)TM. The micromirror array is laced at an image plane of an optical system, and is used as a spatial light modulator to redirect portions of the image into the spectrograph. The programmability of the micromirror array allows the creation of arbitrary `slit' patterns as input to the spectrograph. In addition, by controlling the dwell time of each micromirror individually, it is possible to adaptively extend the dynamic range of the spectral imaging system.

  20. Digital Handling and Processing of Remote Sensing Data

    NASA Technical Reports Server (NTRS)

    Algazi, R.

    1972-01-01

    Details of plans for developing a digital image processing facility to handle remote sensing data are reported. Also given are programs for data acquisition and handling, systems for use in programming various digital image processing tasks, and algorithms for feature enhancement.

  1. Digital TV processing system

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Two digital video data compression systems directly applicable to the Space Shuttle TV Communication System were described: (1) For the uplink, a low rate monochrome data compressor is used. The compression is achieved by using a motion detection technique in the Hadamard domain. To transform the variable source rate into a fixed rate, an adaptive rate buffer is provided. (2) For the downlink, a color data compressor is considered. The compression is achieved first by intra-color transformation of the original signal vector, into a vector which has lower information entropy. Then two-dimensional data compression techniques are applied to the Hadamard transformed components of this last vector. Mathematical models and data reliability analyses were also provided for the above video data compression techniques transmitted over a channel encoded Gaussian channel. It was shown that substantial gains can be achieved by the combination of video source and channel coding.

  2. Digital image watermarking using visual models

    NASA Astrophysics Data System (ADS)

    Podilchuk, Christine I.; Zeng, Wenjun

    1997-06-01

    The huge success of the Internet permits the transmission and wide distribution and access of electronic data in an effortless manner. Content providers are faced with the challenge of how to protect their electronic data. This problem has generated a flurry of recent research activity in the area of digital watermarking of electronic content for copyright protection. Unlike the traditional visible watermark found on paper, the challenge here is to introduce a digital watermark that does not alter the perceived quality of the electronic content while being extremely robust to attack. For instance, in the case of image data, editing the picture or illegal tampering should not destroy or alter the watermark. Equally important, the watermark should not alter the perceived visual quality of the image. From a signal processing viewpoint, the two basic requirements for an effective watermarking scheme, robustness and transparency, conflict with each other. We propose a watermarking technique for digital images that is based on utilizing visual models which have been developed in the context of image compression. Specifically, we propose a watermarking scheme where visual models are used to determine image dependent modulation masks for watermark insertion. In other words, for each image we can determine the maximum amount of watermark signal that each portion of the image can tolerate without affecting the visual quality of the image. This allow us to provide the maximum strength watermark which in turn, is extremely robust to common image processing and editing such as JPEG compression, rescaling, and cropping. We have watermarking results in a DCT framework as well as a wavelet framework. The DCT framework allows the direct insertion of watermarks to JPEG -- compressed data whereas the wavelet based scheme provides a framework where we can take advantage of both a local and global approach. Our scheme is shown to provide dramatic improvement over the current state

  3. Multiple digital watermarking applied to medical imaging.

    PubMed

    Giakoumaki, A; Pavlopoulos, S; Koutsouris, D

    2005-01-01

    Beyond its already established wide range of applications, digital watermarking has recently started to gain a foothold in the healthcare sector. The paper discusses the potential of multiple watermarking to address a number of health information management issues, such as protection of sensitive data, origin and data authentication, image archiving and retrieval. A wavelet-based multiple watermarking scheme focusing on these medical-oriented applications is presented; the scheme allows the physician to define a Region of Interest, whose diagnostic value is explicitly protected throughout the embedding process, since the only additional information inserted therein is for the purpose of integrity control. The rest part of the image casts multiple watermarks conveying the physician's digital signature, patient's sensitive data, and keywords allowing image retrieval. In order to increase data robustness, a form of hybrid coding is applied, which includes repetitive embedding of BCH encoded watermarks.

  4. Digital Imaging Techniques for Radiotherapy Treatment Verification

    NASA Astrophysics Data System (ADS)

    Leszczynski, Konrad Wojciech

    The curative effect of ionizing radiation depends strongly upon the precision with which dose is delivered to the prescribed target volume. The requirement for high geometric accuracy in patient positioning is even more stringent where complex treatment techniques are used, such as conformal, dynamic arc or truly 3-D (non-coplanar) beams. It is expected that digital on-line portal imaging devices will play a key role in the monitoring of radiation therapy treatments. Different approaches to on-line portal image acquisition have been compared, and the basic imaging properties of a video portal imager have been evaluated and discussed in this thesis. Analysis of the system performance indicates the most efficient ways to effect improvements in spatial resolution and signal-to-noise ratio. Digital image processing techniques for noise suppression and contrast enhancement have been developed and implemented in order to facilitate visual analysis of on-line portal images. Results obtained with phantom and clinical images indicate that improvement in image quality can be achieved using adaptive filtering and local histogram modification. A novel study of observer performance with on-line portal images showed that enhancement of contrast by selective local histogram modification significantly improves perceptibility of anatomical landmarks and assures higher accuracy in quantitative computer-assisted treatment verification. Fully automated treatment verification is the ultimate goal of on-line digital portal imaging. It should include analysis of size and shape of the radiation field as well as evaluation of placement of the field with respect to the internal anatomy of the patient. A computerized technique, has been developed, for extraction of the treatment field edges and for parametrization of the field, and examples of its application to automated analysis of size and shape of the radiation field are presented.

  5. Detecting Copy Move Forgery In Digital Images

    NASA Astrophysics Data System (ADS)

    Gupta, Ashima; Saxena, Nisheeth; Vasistha, S. K.

    2012-03-01

    In today's world several image manipulation software's are available. Manipulation of digital images has become a serious problem nowadays. There are many areas like medical imaging, digital forensics, journalism, scientific publications, etc, where image forgery can be done very easily. To determine whether a digital image is original or doctored is a big challenge. To find the marks of tampering in a digital image is a challenging task. The detection methods can be very useful in image forensics which can be used as a proof for the authenticity of a digital image. In this paper we propose the method to detect region duplication forgery by dividing the image into overlapping block and then perform searching to find out the duplicated region in the image.

  6. Improved Digital Image Correlation method

    NASA Astrophysics Data System (ADS)

    Mudassar, Asloob Ahmad; Butt, Saira

    2016-12-01

    Digital Image Correlation (DIC) is a powerful technique which is used to correlate two image segments to determine the similarity between them. A correlation image is formed which gives a peak known as correlation peak. If the two image segments are identical the peak is known as auto-correlation peak otherwise it is known as cross correlation peak. The location of the peak in a correlation image gives the relative displacement between the two image segments. Use of DIC for in-plane displacement and deformation measurements in Electronic Speckle Photography (ESP) is well known. In ESP two speckle images are correlated using DIC and relative displacement is measured. We are presenting background review of ESP and disclosing a technique based on DIC for improved relative measurements which we regard as the improved DIC method. Simulation and experimental results reveal that the proposed improved-DIC method is superior to the conventional DIC method in two aspects, in resolution and in the availability of reference position in displacement measurements.

  7. Perceptual watermarks for digital images and video

    NASA Astrophysics Data System (ADS)

    Wolfgang, Raymond B.; Podilchuk, Christine I.; Delp, Edward J., III

    1999-04-01

    The growth of new imaging technologies has created a need for techniques that can be used for copyright protection of digital images. One approach for copyright protection is to introduce an invisible signal known as a digital watermark in the image. In this paper, we describe digital image watermarking techniques known as perceptually watermarks that are designed to exploit aspects of the human visual system in order to produce a transparent, yet robust watermark.

  8. Development of a prototype chest digital tomosynthesis (CDT) R/F system with fast image reconstruction using graphics processing unit (GPU) programming

    NASA Astrophysics Data System (ADS)

    Choi, Sunghoon; Lee, Seungwan; Lee, Haenghwa; Lee, Donghoon; Choi, Seungyeon; Shin, Jungwook; Seo, Chang-Woo; Kim, Hee-Joung

    2017-03-01

    Digital tomosynthesis offers the advantage of low radiation doses compared to conventional computed tomography (CT) by utilizing small numbers of projections ( 80) acquired over a limited angular range. It produces 3D volumetric data, although there are artifacts due to incomplete sampling. Based upon these characteristics, we developed a prototype digital tomosynthesis R/F system for applications in chest imaging. Our prototype chest digital tomosynthesis (CDT) R/F system contains an X-ray tube with high power R/F pulse generator, flat-panel detector, R/F table, electromechanical radiographic subsystems including a precise motor controller, and a reconstruction server. For image reconstruction, users select between analytic and iterative reconstruction methods. Our reconstructed images of Catphan700 and LUNGMAN phantoms clearly and rapidly described the internal structures of phantoms using graphics processing unit (GPU) programming. Contrast-to-noise ratio (CNR) values of the CTP682 module of Catphan700 were higher in images using a simultaneous algebraic reconstruction technique (SART) than in those using filtered back-projection (FBP) for all materials by factors of 2.60, 3.78, 5.50, 2.30, 3.70, and 2.52 for air, lung foam, low density polyethylene (LDPE), Delrin® (acetal homopolymer resin), bone 50% (hydroxyapatite), and Teflon, respectively. Total elapsed times for producing 3D volume were 2.92 s and 86.29 s on average for FBP and SART (20 iterations), respectively. The times required for reconstruction were clinically feasible. Moreover, the total radiation dose from our system (5.68 mGy) was lower than that of conventional chest CT scan. Consequently, our prototype tomosynthesis R/F system represents an important advance in digital tomosynthesis applications.

  9. Digital image fusion systems: color imaging and low-light targets

    NASA Astrophysics Data System (ADS)

    Estrera, Joseph P.

    2009-05-01

    This paper presents digital image fusion (enhanced A+B) systems in color imaging and low light target applications. This paper will discuss first the digital sensors that are utilized in the noted image fusion applications which is a 1900x1086 (high definition format) CMOS imager coupled to a Generation III image intensifier for the visible/near infrared (NIR) digital sensor and 320x240 or 640x480 uncooled microbolometer thermal imager for the long wavelength infrared (LWIR) digital sensor. Performance metrics for these digital imaging sensors will be presented. The digital image fusion (enhanced A+B) process will be presented in context of early fused night vision systems such as the digital image fused system (DIFS) and the digital enhanced night vision goggle and later, the long range digitally fused night vision sighting system. Next, this paper will discuss the effects of user display color in a dual color digital image fusion system. Dual color image fusion schemes such as Green/Red, Cyan/Yellow, and White/Blue for image intensifier and thermal infrared sensor color representation, respectively, are discussed. Finally, this paper will present digitally fused imagery and image analysis of long distance targets in low light from these digital fused systems. The result of this image analysis with enhanced A+B digital image fusion systems is that maximum contrast and spatial resolution is achieved in a digital fusion mode as compared to individual sensor modalities in low light, long distance imaging applications. Paper has been cleared by DoD/OSR for Public Release under Ref: 08-S-2183 on August 8, 2008.

  10. Advanced digital SAR processing study

    NASA Technical Reports Server (NTRS)

    Martinson, L. W.; Gaffney, B. P.; Liu, B.; Perry, R. P.; Ruvin, A.

    1982-01-01

    A highly programmable, land based, real time synthetic aperture radar (SAR) processor requiring a processed pixel rate of 2.75 MHz or more in a four look system was designed. Variations in range and azimuth compression, number of looks, range swath, range migration and SR mode were specified. Alternative range and azimuth processing algorithms were examined in conjunction with projected integrated circuit, digital architecture, and software technologies. The advaced digital SAR processor (ADSP) employs an FFT convolver algorithm for both range and azimuth processing in a parallel architecture configuration. Algorithm performace comparisons, design system design, implementation tradeoffs and the results of a supporting survey of integrated circuit and digital architecture technologies are reported. Cost tradeoffs and projections with alternate implementation plans are presented.

  11. Digital holography and 3-D imaging.

    PubMed

    Banerjee, Partha; Barbastathis, George; Kim, Myung; Kukhtarev, Nickolai

    2011-03-01

    This feature issue on Digital Holography and 3-D Imaging comprises 15 papers on digital holographic techniques and applications, computer-generated holography and encryption techniques, and 3-D display. It is hoped that future work in the area leads to innovative applications of digital holography and 3-D imaging to biology and sensing, and to the development of novel nonlinear dynamic digital holographic techniques.

  12. Image Acquisition and Quality in Digital Radiography.

    PubMed

    Alexander, Shannon

    2016-09-01

    Medical imaging has undergone dramatic changes and technological breakthroughs since the introduction of digital radiography. This article presents information on the development of digital radiography and types of digital radiography systems. Aspects of image quality and radiation exposure control are highlighted as well. In addition, the article includes related workplace changes and medicolegal considerations in the digital radiography environment. ©2016 American Society of Radiologic Technologists.

  13. Image post-processing in dental practice.

    PubMed

    Gormez, Ozlem; Yilmaz, Hasan Huseyin

    2009-10-01

    Image post-processing of dental digital radiographs, a function which used commonly in dental practice is presented in this article. Digital radiography has been available in dentistry for more than 25 years and its use by dental practitioners is steadily increasing. Digital acquisition of radiographs enables computer-based image post-processing to enhance image quality and increase the accuracy of interpretation. Image post-processing applications can easily be practiced in dental office by a computer and image processing programs. In this article, image post-processing operations such as image restoration, image enhancement, image analysis, image synthesis, and image compression, and their diagnostic efficacy is described. In addition this article provides general dental practitioners with a broad overview of the benefits of the different image post-processing operations to help them understand the role of that the technology can play in their practices.

  14. Sonorous images through digital holographic images

    NASA Astrophysics Data System (ADS)

    Azevedo, Isabel; Sandford-Richardson, Elizabeth

    2017-03-01

    The art of the last fifty years has significantly surrounded the presence of the body, the relationship between human and interactive technologies. Today in interactive art, there are not only representations that speak of the body but actions and behaviours that involve the body. In holography, the image appears and disappears from the observer's vision field; because the holographic image is light, we can see multidimensional spaces, shapes and colours existing on the same time, presence and absence of the image on the holographic plate. And the image can be flowing in front of the plate that sometimes people try touching it with his hands. That means, to the viewer will be interactive events, with no beginning or end that can be perceived in any direction, forward or backward, depending on the relative position and the time the viewer spends in front of the hologram. To explore that feature we are proposing an installation with four holograms, and several sources of different kind of sounds connected with each hologram. When viewers will move in front of each hologram they will activate different sources of sound. The search is not only about the images in the holograms, but also the looking for different types of sounds that this demand will require. The digital holograms were produced using the HoloCam Portable Light System with the 35 mm camera Canon 700D to capture image information, it was then edited on computer using the Motion 5 and Final Cut Pro X programs.

  15. The NCSA Astronomy Digital Image Library

    NASA Astrophysics Data System (ADS)

    Plante, Raymond L.; Crutcher, Richard M.; Sharpe, Randall K.

    We announce the opening of the NCSA Astronomy Digital Image Library (URL = http://imagelib.ncsa.uiuc.edu/imagelib.html). The mission of the Library is to collect fully processed astronomical images in FITS format and make them available to the research community and the general public via the World Wide Web. Users may search the Library's contents, browse preview images, and download the full FITS images. All items contained in the Library may either be accessed via the HTML interface or through unique URNs. The latter method allows for easy linking to Library items from other databases or hypertext documents on the Web. The Library is expected to provide many benefits not only to users retrieving information but also to authors who add to the images in the Library's collection.

  16. A new full-field digital mammography system with and without the use of an advanced post-processing algorithm: comparison of image quality and diagnostic performance.

    PubMed

    Ahn, Hye Shin; Kim, Sun Mi; Jang, Mijung; Yun, Bo La; Kim, Bohyoung; Ko, Eun Sook; Han, Boo-Kyung; Chang, Jung Min; Yi, Ann; Cho, Nariya; Moon, Woo Kyung; Choi, Hye Young

    2014-01-01

    To compare new full-field digital mammography (FFDM) with and without use of an advanced post-processing algorithm to improve image quality, lesion detection, diagnostic performance, and priority rank. During a 22-month period, we prospectively enrolled 100 cases of specimen FFDM mammography (Brestige®), which was performed alone or in combination with a post-processing algorithm developed by the manufacturer: group A (SMA), specimen mammography without application of "Mammogram enhancement ver. 2.0"; group B (SMB), specimen mammography with application of "Mammogram enhancement ver. 2.0". Two sets of specimen mammographies were randomly reviewed by five experienced radiologists. Image quality, lesion detection, diagnostic performance, and priority rank with regard to image preference were evaluated. Three aspects of image quality (overall quality, contrast, and noise) of the SMB were significantly superior to those of SMA (p < 0.05). SMB was significantly superior to SMA for visualizing calcifications (p < 0.05). Diagnostic performance, as evaluated by cancer score, was similar between SMA and SMB. SMB was preferred to SMA by four of the five reviewers. The post-processing algorithm may improve image quality with better image preference in FFDM than without use of the software.

  17. A New Full-Field Digital Mammography System with and without the Use of an Advanced Post-Processing Algorithm: Comparison of Image Quality and Diagnostic Performance

    PubMed Central

    Ahn, Hye Shin; Jang, Mijung; Yun, Bo La; Kim, Bohyoung; Ko, Eun Sook; Han, Boo-Kyung; Chang, Jung Min; Yi, Ann; Cho, Nariya; Moon, Woo Kyung; Choi, Hye Young

    2014-01-01

    Objective To compare new full-field digital mammography (FFDM) with and without use of an advanced post-processing algorithm to improve image quality, lesion detection, diagnostic performance, and priority rank. Materials and Methods During a 22-month period, we prospectively enrolled 100 cases of specimen FFDM mammography (Brestige®), which was performed alone or in combination with a post-processing algorithm developed by the manufacturer: group A (SMA), specimen mammography without application of "Mammogram enhancement ver. 2.0"; group B (SMB), specimen mammography with application of "Mammogram enhancement ver. 2.0". Two sets of specimen mammographies were randomly reviewed by five experienced radiologists. Image quality, lesion detection, diagnostic performance, and priority rank with regard to image preference were evaluated. Results Three aspects of image quality (overall quality, contrast, and noise) of the SMB were significantly superior to those of SMA (p < 0.05). SMB was significantly superior to SMA for visualizing calcifications (p < 0.05). Diagnostic performance, as evaluated by cancer score, was similar between SMA and SMB. SMB was preferred to SMA by four of the five reviewers. Conclusion The post-processing algorithm may improve image quality with better image preference in FFDM than without use of the software. PMID:24843234

  18. Storage and retrieval of large digital images

    DOEpatents

    Bradley, J.N.

    1998-01-20

    Image compression and viewing are implemented with (1) a method for performing DWT-based compression on a large digital image with a computer system possessing a two-level system of memory and (2) a method for selectively viewing areas of the image from its compressed representation at multiple resolutions and, if desired, in a client-server environment. The compression of a large digital image I(x,y) is accomplished by first defining a plurality of discrete tile image data subsets T{sub ij}(x,y) that, upon superposition, form the complete set of image data I(x,y). A seamless wavelet-based compression process is effected on I(x,y) that is comprised of successively inputting the tiles T{sub ij}(x,y) in a selected sequence to a DWT routine, and storing the resulting DWT coefficients in a first primary memory. These coefficients are periodically compressed and transferred to a secondary memory to maintain sufficient memory in the primary memory for data processing. The sequence of DWT operations on the tiles T{sub ij}(x,y) effectively calculates a seamless DWT of I(x,y). Data retrieval consists of specifying a resolution and a region of I(x,y) for display. The subset of stored DWT coefficients corresponding to each requested scene is determined and then decompressed for input to an inverse DWT, the output of which forms the image display. The repeated process whereby image views are specified may take the form an interaction with a computer pointing device on an image display from a previous retrieval. 6 figs.

  19. Storage and retrieval of large digital images

    DOEpatents

    Bradley, Jonathan N.

    1998-01-01

    Image compression and viewing are implemented with (1) a method for performing DWT-based compression on a large digital image with a computer system possessing a two-level system of memory and (2) a method for selectively viewing areas of the image from its compressed representation at multiple resolutions and, if desired, in a client-server environment. The compression of a large digital image I(x,y) is accomplished by first defining a plurality of discrete tile image data subsets T.sub.ij (x,y) that, upon superposition, form the complete set of image data I(x,y). A seamless wavelet-based compression process is effected on I(x,y) that is comprised of successively inputting the tiles T.sub.ij (x,y) in a selected sequence to a DWT routine, and storing the resulting DWT coefficients in a first primary memory. These coefficients are periodically compressed and transferred to a secondary memory to maintain sufficient memory in the primary memory for data processing. The sequence of DWT operations on the tiles T.sub.ij (x,y) effectively calculates a seamless DWT of I(x,y). Data retrieval consists of specifying a resolution and a region of I(x,y) for display. The subset of stored DWT coefficients corresponding to each requested scene is determined and then decompressed for input to an inverse DWT, the output of which forms the image display. The repeated process whereby image views are specified may take the form an interaction with a computer pointing device on an image display from a previous retrieval.

  20. Image processing utilizing an APL interface

    NASA Astrophysics Data System (ADS)

    Zmola, Carl; Kapp, Oscar H.

    1991-03-01

    The past few years have seen the growing use of digital techniques in the analysis of electron microscope image data. This trend is driven by the need to maximize the information extracted from the electron micrograph by submitting its digital representation to the broad spectrum of analytical techniques made available by the digital computer. We are developing an image processing system for the analysis of digital images obtained with a scanning transmission electron microscope (STEM) and a scanning electron microscope (SEM). This system, run on an IBM PS/2 model 70/A21, uses menu-based image processing and an interactive APL interface which permits the direct manipulation of image data.

  1. [Effects of image post-processing parameters on digital radiography chest radiograph for the diagnosis of pneumoconiosis].

    PubMed

    Chen, Jun-Qiang; Jiang, Zhao-Qiang; Zhou, Bin; Zhu, Qiang; Liu, Bin; Zhang, Xing

    2012-01-01

    To explore the effects of image post-processing parameters on DR chest radiograph for the diagnosis of pneumoconiosis. Eighty three coal miners were examined with high-kV and DR chest radiographs at the same time. Image post-processing parameters (density, contrast and so on) were designed in a Philips Essenta DR machine were designed, then differences of image quality between high-kV and DR chest radiographs were compared. After regulating image and proceeding the parameters, the OD (optical density) values of high density areas in the upper-middle lung fields, subphrenic and direct exposure areas were 1.58 +/- 0.10, 0.23 +/- 0.02 and 2.80 +/- 0.21, respectively. The quality of chest films met the requirements of diagnostic criteria of pneumoconiosis. The rate of excellent chest films for DR chest radiograph was 95.18%, which was significantly higher than that (80.72%) for high-kV chest radiograph (P < 0.01). Appropriate parameters of image post-processing can make DR chest radiograph to meet the requirements of chest radiograph quality for the diagnosis of pneumoconiosis.

  2. Forensic Analysis of Digital Image Tampering

    DTIC Science & Technology

    2004-12-01

    will pave the way for Chapter 3, which deals with the methodology of an experimental design for image forgery detection . 2.2 Digital Watermarking ...example is presented to determine what effects an invisible watermark has on the results of each detection method. The host image is similar to that in...Digital Watermarking ............................................................................................... 7 2.3 Unknown Image Origin

  3. SOFT-1: Imaging Processing Software

    NASA Technical Reports Server (NTRS)

    1984-01-01

    Five levels of image processing software are enumerated and discussed: (1) logging and formatting; (2) radiometric correction; (3) correction for geometric camera distortion; (4) geometric/navigational corrections; and (5) general software tools. Specific concerns about access to and analysis of digital imaging data within the Planetary Data System are listed.

  4. The future of digital imaging in dentistry.

    PubMed

    Miles, D A; Razzano, M R

    2000-04-01

    Digital radiographic imaging in dentistry has matured. All the reasons dentists have cited for keeping conventional, film-based systems have been refuted: cost, sensors, storage, and training are not issues. There are many reasons to switch to digital. This article outlines external factors that dentists may not have considered that will influence the way they conduct business in their offices related to radiographic imaging. The evidence points to the inevitable adoption of digital imaging systems.

  5. Utility of Digital Stereo Images for Optic Disc Evaluation

    PubMed Central

    Ying, Gui-shuang; Pearson, Denise J.; Bansal, Mayank; Puri, Manika; Miller, Eydie; Alexander, Judith; Piltz-Seymour, Jody; Nyberg, William; Maguire, Maureen G.; Eledath, Jayan; Sawhney, Harpreet

    2010-01-01

    Purpose. To assess the suitability of digital stereo images for optic disc evaluations in glaucoma. Methods. Stereo color optic disc images in both digital and 35-mm slide film formats were acquired contemporaneously from 29 subjects with various cup-to-disc ratios (range, 0.26–0.76; median, 0.475). Using a grading scale designed to assess image quality, the ease of visualizing optic disc features important for glaucoma diagnosis, and the comparative diameters of the optic disc cup, experienced observers separately compared the primary digital stereo images to each subject's 35-mm slides, to scanned images of the same 35-mm slides, and to grayscale conversions of the digital images. Statistical analysis accounted for multiple gradings and comparisons and also assessed image formats under monoscopic viewing. Results. Overall, the quality of primary digital color images was judged superior to that of 35-mm slides (P < 0.001), including improved stereo (P < 0.001), but the primary digital color images were mostly equivalent to the scanned digitized images of the same slides. Color seemingly added little to grayscale optic disc images, except that peripapillary atrophy was best seen in color (P < 0.0001); both the nerve fiber layer (P < 0.0001) and the paths of blood vessels on the optic disc (P < 0.0001) were best seen in grayscale. The preference for digital over film images was maintained under monoscopic viewing conditions. Conclusions. Digital stereo optic disc images are useful for evaluating the optic disc in glaucoma and allow the application of advanced image processing applications. Grayscale images, by providing luminance distinct from color, may be informative for assessing certain features. PMID:20505199

  6. Fuzzy Logic Enhanced Digital PIV Processing Software

    NASA Technical Reports Server (NTRS)

    Wernet, Mark P.

    1999-01-01

    Digital Particle Image Velocimetry (DPIV) is an instantaneous, planar velocity measurement technique that is ideally suited for studying transient flow phenomena in high speed turbomachinery. DPIV is being actively used at the NASA Glenn Research Center to study both stable and unstable operating conditions in a high speed centrifugal compressor. Commercial PIV systems are readily available which provide near real time feedback of the PIV image data quality. These commercial systems are well designed to facilitate the expedient acquisition of PIV image data. However, as with any general purpose system, these commercial PIV systems do not meet all of the data processing needs required for PIV image data reduction in our compressor research program. An in-house PIV PROCessing (PIVPROC) code has been developed for reducing PIV data. The PIVPROC software incorporates fuzzy logic data validation for maximum information recovery from PIV image data. PIVPROC enables combined cross-correlation/particle tracking wherein the highest possible spatial resolution velocity measurements are obtained.

  7. Digital Image Compression Using Artificial Neural Networks

    NASA Technical Reports Server (NTRS)

    Serra-Ricart, M.; Garrido, L.; Gaitan, V.; Aloy, A.

    1993-01-01

    The problem of storing, transmitting, and manipulating digital images is considered. Because of the file sizes involved, large amounts of digitized image information are becoming common in modern projects. Our goal is to described an image compression transform coder based on artificial neural networks techniques (NNCTC). A comparison of the compression results obtained from digital astronomical images by the NNCTC and the method used in the compression of the digitized sky survey from the Space Telescope Science Institute based on the H-transform is performed in order to assess the reliability of the NNCTC.

  8. Digital image processing of the CCD (SRT) positional observations of two satellites (Ariel and Titania) of Uranus.

    NASA Astrophysics Data System (ADS)

    Peng, Qingyu; Liu, Weiwei; Wang, Feng

    1998-08-01

    The positional determination of natural satellites is very important in astrometry and celestial mechanics. Some researchers have performed very good astrometric observations of Uranian satellites with a new image processing technique. The authors compared the methods without and with halo-processing for the CCD (SRT-Separated Readout Technique) observations of Ariel and Titania carried out with the 1-meter telescope of Yunnan Observatory. When the two satellites were used to determine the CCD scale and orientation, it was clarified that the Uranian halo-processing is very important for the positional determination of satellites.

  9. Digital subtraction angiography: principles and pitfalls of image improvement techniques.

    PubMed

    Levin, D C; Schapiro, R M; Boxt, L M; Dunham, L; Harrington, D P; Ergun, D L

    1984-09-01

    The technology of imaging methods in digital subtraction angiography (DSA) is discussed in detail. Areas covered include function of the video camera in both interlaced and sequential scan modes, digitization by the analog-to-digital converter, logarithmic signal processing, dose rates, and acquisition of images using frame integration and pulsed-sequential techniques. Also discussed are various methods of improving image content and quality by both hardware and software modifications. These include the development of larger image intensifiers, larger matrices, video camera improvements, reregistration, hybrid subtraction, matched filtering, recursive filtering, DSA tomography, and edge enhancement.

  10. Digital document imaging systems: An overview and guide

    NASA Technical Reports Server (NTRS)

    1990-01-01

    This is an aid to NASA managers in planning the selection of a Digital Document Imaging System (DDIS) as a possible solution for document information processing and storage. Intended to serve as a manager's guide, this document contains basic information on digital imaging systems, technology, equipment standards, issues of interoperability and interconnectivity, and issues related to selecting appropriate imaging equipment based upon well defined needs.

  11. Digital imaging applications in anatomic pathology.

    PubMed

    Leong, F Joel W-M; Leong, Anthony S-Y

    2003-03-01

    Digital imaging has progressed at a rapid rate and is likely to eventually replace chemical photography in most areas of professional and amateur digital image acquisition. In pathology, digital microscopy has implications beyond that of taking a photograph. The arguments for adopting this new medium are compelling, and given similar developments in other areas of pathology and radiologic imaging, acceptance of the digital medium should be viewed as a component of the technological evolution of the laboratory. A digital image may be stored, replicated, catalogued, employed for educational purposes, transmitted for further interpretation (telepathology), analyzed for salient features (medical vision/image analysis), or form part of a wider digital healthcare strategy. Despite advances in digital camera technology, good image acquisition still requires good microscope optics and the correct calibration of all system components, something which many neglect. The future of digital imaging in pathology is very promising and new applications in the fields of automated quantification and interpretation are likely to have profound long-term influence on the practice of anatomic pathology. This paper discusses the state of the art of digital imaging in anatomic pathology.

  12. Going digital: image preparation for biomedical publishing.

    PubMed

    Schenk, M P; Manning, R J; Paalman, M H

    1999-08-15

    Authors are more often being held responsible for readying their own data figures for digital publication by scanning them at the proper resolution and preparing them for presentation in both print and on-line journals. In this manner, the visuals can be printed at the highest quality the publisher can provide and be ready for rapid electronic distribution on the Internet. Therefore, authors must become knowledgeable in the visual preparation process in order to generate electronic images that will be as true a representation of the original image as possible. Perfecting this procedure can be a learning experience and often requires some experimentation. When accomplished, the author will have more control of exactly how the images will look before they are published. In addition to the scan resolution, the type of digital scanner and software applications used are very important, and instruction manuals should be followed closely so as to understand the full potential of the digitizing equipment. Anat Rec (New Anat): 257:128-136, 1999.

  13. Digital image processing for quantification through full flow field tracing (FFFT) in narrow geometries at low Reynolds numbers

    NASA Technical Reports Server (NTRS)

    Braun, M. J.; Batur, C.; Karavelakis, G.

    1988-01-01

    This paper introduces a computer based image processing technique to the field of nonintrusive velocity measurements in fluid mechanics. The method is presented with two alternatives: the first is involving intense interaction between the operator and the computer system; the second is a first generation artificial intelligence based system, where a set of initially imputed rules replaces the operator. The methods are applied to flow in narrow gaps.

  14. Three-dimensional digital breast histopathology imaging

    NASA Astrophysics Data System (ADS)

    Clarke, G. M.; Peressotti, C.; Mawdsley, G. E.; Eidt, S.; Ge, M.; Morgan, T.; Zubovits, J. T.; Yaffe, M. J.

    2005-04-01

    We have developed a digital histology imaging system that has the potential to improve the accuracy of surgical margin assessment in the treatment of breast cancer by providing finer sampling and 3D visualization. The system is capable of producing a 3D representation of histopathology from an entire lumpectomy specimen. We acquire digital photomicrographs of a stack of large (120 x 170 mm) histology slides cut serially through the entire specimen. The images are then registered and displayed in 2D and 3D. This approach dramatically improves sampling and can improve visualization of tissue structures compared to current, small-format histology. The system consists of a brightfield microscope, adapted with a freeze-frame digital video camera and a large, motorized translation stage. The image of each slide is acquired as a mosaic of adjacent tiles, each tile representing one field-of-view of the microscope, and the mosaic is assembled into a seamless composite image. The assembly is done by a program developed to build image sets at six different levels within a multiresolution pyramid. A database-linked viewing program has been created to efficiently register and display the animated stack of images, which occupies about 80 GB of disk space per lumpectomy at full resolution, on a high-resolution (3840 x 2400 pixels) colour monitor. The scanning or tiling approach to digitization is inherently susceptible to two artefacts which disrupt the composite image, and which impose more stringent requirements on system performance. Although non-uniform illumination across any one isolated tile may not be discernible, the eye readily detects this non-uniformity when the entire assembly of tiles is viewed. The pattern is caused by deficiencies in optical alignment, spectrum of the light source, or camera corrections. The imaging task requires that features as small as 3.2 &mum in extent be seamlessly preserved. However, inadequate accuracy in positioning of the translation

  15. Digital image processing for the acquisition of graphic similarity of the distributional patterns between cutaneous lesions of linear scleroderma and Blaschko's lines.

    PubMed

    Jue, Mihn Sook; Kim, Moon Hwan; Ko, Joo Yeon; Lee, Chang Woo

    2011-08-01

    The aim of this study is to objectively evaluate whether linear scleroderma (LS) follows Blaschko's lines (BL) in Korean patients using digital image processing. Thirty-two patients with LS were examined. According to the patients' clinical photographs, their skin lesions were plotted on the head and body charts. With the aid of graphics software, a digital image was produced that included an overlay of all the individual lesions and was used to compare the graphics with the published BL. To investigate the image similarity between the graphic patterns of the LS and BL, each case was analyzed by means of Hough transformations and Czekanowski's methods. The comparative investigation of the graphic similarity of distributional patterns between the LS and BL showed that Czekanowski's similarity index was 0.947 on average. In conclusion, our objective results suggest that the graphic patterns of the distribution of the LS skin lesions showed a high degree of similarity and in fact were almost identical to that of BL which may be the lines of embryonic development of the skin. This finding may suggest that some developmental factors during the embryological age could constitute the cause of LS. © 2011 Japanese Dermatological Association.

  16. System for objective assessment of image differences in digital cinema

    NASA Astrophysics Data System (ADS)

    Fliegel, Karel; Krasula, Lukáš; Páta, Petr; Myslík, Jiří; Pecák, Josef; Jícha, Marek

    2014-09-01

    There is high demand for quick digitization and subsequent image restoration of archived film records. Digitization is very urgent in many cases because various invaluable pieces of cultural heritage are stored on aging media. Only selected records can be reconstructed perfectly using painstaking manual or semi-automatic procedures. This paper aims to answer the question what are the quality requirements on the restoration process in order to obtain acceptably close visual perception of the digitally restored film in comparison to the original analog film copy. This knowledge is very important to preserve the original artistic intention of the movie producers. Subjective experiment with artificially distorted images has been conducted in order to answer the question what is the visual impact of common image distortions in digital cinema. Typical color and contrast distortions were introduced and test images were presented to viewers using digital projector. Based on the outcome of this subjective evaluation a system for objective assessment of image distortions has been developed and its performance tested. The system utilizes calibrated digital single-lens reflex camera and subsequent analysis of suitable features of images captured from the projection screen. The evaluation of captured image data has been optimized in order to obtain predicted differences between the reference and distorted images while achieving high correlation with the results of subjective assessment. The system can be used to objectively determine the difference between analog film and digital cinema images on the projection screen.

  17. Investigation of the spray characteristics for a secondary fuel injection nozzle using a digital image processing method

    NASA Astrophysics Data System (ADS)

    Jeong, Haeyoung; Lee, Kihyung; Ikeda, Yuji

    2007-05-01

    There are many ways to reduce diesel engine exhaust emissions. However, NOx emission is difficult to reduce because the hydrocarbon (HC) concentration in a diesel engine is not sufficient for NOx conversion. Therefore, in order to create stoichiometric conditions in the De-NOx catalyst, a secondary injection system is designed to inject liquid HC into the exhaust pipe. The atomization and distribution characteristics of the HC injected from a secondary injector are key technologies to obtain a high NOx conversion because inhomogeneous droplets of injected HC cause not only high fuel consumption but also deterioration of NOx emission. This paper describes the spray characteristics of a secondary injector including the spray angle, penetration length and breakup behaviour of the spray to optimize the reduction rate of the NOx catalyst. In this study, various optical diagnostics were applied to investigate these spray characteristics, the atomization mechanism and spray developing process. The visualization and image processing method for the spray pulsation were developed by high speed photography. The influence of the fuel supply pressure on the spray behaviour and a more detailed spray developing process have been analysed experimentally using image processing. Finally, the experimental results were used to correlate the spray structure to the injection system performance and to provide a design guide for a secondary injector nozzle.

  18. A Prototype Digital Image Management System

    PubMed Central

    Dwyer, Samuel J.; Templeton, Arch W.; Anderson, William H.; Tarlton, Mark A.; Hensley, Kenneth S.; Lee, Kyo Rak; Batnitzky, Solomon; Rosenthal, Stanton J.; Johnson, Joy A.; Preston, David F.

    1983-01-01

    A prototype digital image management system has been designed, implemented and is being evaluated by our department. The system satisfies two major requirements: (a) an on-line access, rapid response microcomputer network providing 9 day archiving of digital data; (b) a long-term, low demand archiving system. This paper provides an estimate of the cost of the system, the potential cost-savings, and identifies the digital data throughput using the Ethernet communications protocol. ImagesFigure 4

  19. Digital Imaging: An Adobe Photoshop Course

    ERIC Educational Resources Information Center

    Cobb, Kristine

    2007-01-01

    This article introduces digital imaging, an Adobe Photoshop course at Shrewsbury High School in Shrewsbury, Massachusetts. Students are able to earn art credits to graduate by successfully completing the course. Digital imaging must cover art criteria as well as technical skills. The course begins with tutorials created by the instructor and other…

  20. Ethical Implications of Digital Imaging in Photojournalism.

    ERIC Educational Resources Information Center

    Terry, Danal; Lasorsa, Dominic L.

    Arguing that the news media are about to adopt digital imaging systems that will have far-reaching implications for the practice of journalism, this paper discusses how the news media is expected to adopt the new technology and explains why the marriage of journalism and digital imaging will create ethical issues with respect to photo manipulation…

  1. Digital Imaging: An Adobe Photoshop Course

    ERIC Educational Resources Information Center

    Cobb, Kristine

    2007-01-01

    This article introduces digital imaging, an Adobe Photoshop course at Shrewsbury High School in Shrewsbury, Massachusetts. Students are able to earn art credits to graduate by successfully completing the course. Digital imaging must cover art criteria as well as technical skills. The course begins with tutorials created by the instructor and other…

  2. Adaptive SVD-Based Digital Image Watermarking

    NASA Astrophysics Data System (ADS)

    Shirvanian, Maliheh; Torkamani Azar, Farah

    Digital data utilization along with the increase popularity of the Internet has facilitated information sharing and distribution. However, such applications have also raised concern about copyright issues and unauthorized modification and distribution of digital data. Digital watermarking techniques which are proposed to solve these problems hide some information in digital media and extract it whenever needed to indicate the data owner. In this paper a new method of image watermarking based on singular value decomposition (SVD) of images is proposed which considers human visual system prior to embedding watermark by segmenting the original image into several blocks of different sizes, with more density in the edges of the image. In this way the original image quality is preserved in the watermarked image. Additional advantages of the proposed technique are large capacity of watermark embedding and robustness of the method against different types of image manipulation techniques.

  3. Camera-based measurement for transverse vibrations of moving catenaries in mine hoists using digital image processing techniques

    NASA Astrophysics Data System (ADS)

    Yao, Jiannan; Xiao, Xingming; Liu, Yao

    2016-03-01

    This paper proposes a novel, non-contact, sensing method to measure the transverse vibrations of hoisting catenaries in mine hoists. Hoisting catenaries are typically moving cables and it is not feasible to use traditional methods to measure their transverse vibrations. In order to obtain the transverse displacements of an arbitrary point in a moving catenary, by superposing a mask image having the predefined reference line perpendicular to the hoisting catenaries on each frame of the processed image sequence, the dynamic intersecting points with a grey value of 0 in the image sequence could be identified. Subsequently, by traversing the coordinates of the pixel with a grey value of 0 and calculating the distance between the identified dynamic points from the reference, the transverse displacements of the selected arbitrary point in the hoisting catenary can be obtained. Furthermore, based on a theoretical model, the reasonability and applicability of the proposed camera-based method were confirmed. Additionally, a laboratory experiment was also carried out, which then validated the accuracy of the proposed method. The research results indicate that the proposed camera-based method is suitable for the measurement of the transverse vibrations of moving cables.

  4. Intravenous Angiocardiography Using Digital Image Processing: Experience With Axial Projections In Normal Pigs And In Pigs With Experimentally Generated Left-To-Right Shunts

    NASA Astrophysics Data System (ADS)

    Bogren, Hugo G.; Bursch, Joachim H.; Brennecke, Rudiger; Heintzen, Paul H.

    1981-11-01

    Computerized digitization and processing of roentgen video images recorded at a rate of 50 per second was tested in intravenous angiocardiography in normal pigs weighing 15 to 20 kg. Roentgen video images were recorded in the 4-chamber view obtained by 30-35 degrees caudocranial angulation of the x-ray tube and 50-60 degrees LAO obliquity in the pig. Significant contrast enhancement was obtained through ECG-gated background subtraction and rescaling after integration of multiple background as well as contrast images. Occasionally, histogram equalization was used to further enhance contrast. To study temporal changes in cardiac motion, time parameter extraction or functional imaging was applied as well. The left and right heart were well visualized after intravenous injection of 1/3-1 cc. 76% Urografin per kg. bodyweight. Special purpose processing like subtraction of the end systolic phase from the end diastolic in the left and right ventricles as well as subtraction of the right ventricular phase from the left ventricular phase was also performed. If the left ventricular end systolic phase was subtracted from the end diastolic, most of the left atrium was also subtracted whereby the left ventricle was seen without continuity or superimposition of the left atrium. Experimentally generated ventricular and atrial septal defects as well as patent ductus arteriosus could be detected using the described technique. The results of the animal experiments became the basis for subsequent applications in children with congenital heart disease.

  5. Intraoral digital radiography: elements of effective imaging.

    PubMed

    Cederberg, Robert

    2012-10-01

    Intraoral digital imaging has evolved from an experimental and sometimes disparaged technique in the mid 1980s to a reliable and ubiquitously used technology today. There are many advantages for use of digital radiographic techniques in dentistry, one of the chief ones being patient dose reduction. However, as important as dose reduction is for safe and effective radiography, practicing dentists would also like to understand the fundamental differences between digital system configurations so they may be able to make an informed choice as to which system best fits their needs. In addition, there has been considerable debate on the following topics: sensor technology; factors associated with image display; optimum techniques for image manipulation; and image storage, retrieval, and archiving. This article provides insight into these and other elements of effective imaging in intraoral digital imaging.

  6. Pixel-level robust digital image correlation.

    PubMed

    Cofaru, Corneliu; Philips, Wilfried; Van Paepegem, Wim

    2013-12-02

    Digital Image Correlation (DIC) is a well-established non-contact optical metrology method. It employs digital image analysis to extract the full-field displacements and strains that occur in objects subjected to external stresses. Despite recent DIC progress, many problematic areas which greatly affect accuracy and that can seldomly be avoided, received very little attention. Problems posed by the presence of sharp displacement discontinuities, reflections, object borders or edges can be linked to the analysed object's properties and deformation. Other problematic areas, such as image noise, localized reflections or shadows are related more to the image acquisition process. This paper proposes a new subset-based pixel-level robust DIC method for in-plane displacement measurement which addresses all of these problems in a straightforward and unified approach, significantly improving DIC measurement accuracy compared to classic approaches. The proposed approach minimizes a robust energy functional which adaptively weighs pixel differences in the motion estimation process. The aim is to limit the negative influence of pixels that present erroneous or inconsistent motions by enforcing local motion consistency. The proposed method is compared to the classic Newton-Raphson DIC method in terms of displacement accuracy in three experiments. The first experiment is numerical and presents three combined problems: sharp displacement discontinuities, missing image information and image noise. The second experiment is a real experiment in which a plastic specimen is developing a lateral crack due to the application of uniaxial stress. The region around the crack presents both reflections that saturate the image intensity levels leading to missing image information, as well as sharp motion discontinuities due to the plastic film rupturing. The third experiment compares the proposed and classic DIC approaches with generic computer vision optical flow methods using images from

  7. Potential application of digital image-processing method and fitted logistic model to the control of oriental fruit moths (Grapholita molesta Busck).

    PubMed

    Zhao, Z G; Rong, E H; Li, S C; Zhang, L J; Zhang, Z W; Guo, Y Q; Ma, R Y

    2016-08-01

    Monitoring of oriental fruit moths (Grapholita molesta Busck) is a prerequisite for its control. This study introduced a digital image-processing method and logistic model for the control of oriental fruit moths. First, five triangular sex pheromone traps were installed separately within each area of 667 m2 in a peach orchard to monitor oriental fruit moths consecutively for 3 years. Next, full view images of oriental fruit moths were collected via a digital camera and then subjected to graying, separation and morphological analysis for automatic counting using MATLAB software. Afterwards, the results of automatic counting were used for fitting a logistic model to forecast the control threshold and key control period. There was a high consistency between automatic counting and manual counting (0.99, P < 0.05). According to the logistic model, oriental fruit moths had four occurrence peaks during a year, with a time-lag of 15-18 days between adult occurrence peak and the larval damage peak. Additionally, the key control period was from 28 June to 3 July each year, when the wormy fruit rate reached up to 5% and the trapping volume was approximately 10.2 per day per trap. Additionally, the key control period for the overwintering generation was 25 April. This study provides an automatic counting method and fitted logistic model with a great potential for application to the control of oriental fruit moths.

  8. Image rejects in general direct digital radiography

    PubMed Central

    Rosanowsky, Tine Blomberg; Jensen, Camilla; Wah, Kenneth Hong Ching

    2015-01-01

    Background The number of rejected images is an indicator of image quality and unnecessary imaging at a radiology department. Image reject analysis was frequent in the film era, but comparably few and small studies have been published after converting to digital radiography. One reason may be a belief that rejects have been eliminated with digitalization. Purpose To measure the extension of deleted images in direct digital radiography (DR), in order to assess the rates of rejects and unnecessary imaging and to analyze reasons for deletions, in order to improve the radiological services. Material and Methods All exposed images at two direct digital laboratories at a hospital in Norway were reviewed in January 2014. Type of examination, number of exposed images, and number of deleted images were registered. Each deleted image was analyzed separately and the reason for deleting the image was recorded. Results Out of 5417 exposed images, 596 were deleted, giving a deletion rate of 11%. A total of 51.3% were deleted due to positioning errors and 31.0% due to error in centering. The examinations with the highest percentage of deleted images were the knee, hip, and ankle, 20.6%, 18.5%, and 13.8% respectively. Conclusion The reject rate is at least as high as the deletion rate and is comparable with previous film-based imaging systems. The reasons for rejection are quite different in digital systems. This falsifies the hypothesis that digitalization would eliminates rejects. A deleted image does not contribute to diagnostics, and therefore is an unnecessary image. Hence, the high rates of deleted images have implications for management, training, education, as well as for quality. PMID:26500784

  9. Image rejects in general direct digital radiography.

    PubMed

    Hofmann, Bjørn; Rosanowsky, Tine Blomberg; Jensen, Camilla; Wah, Kenneth Hong Ching

    2015-10-01

    The number of rejected images is an indicator of image quality and unnecessary imaging at a radiology department. Image reject analysis was frequent in the film era, but comparably few and small studies have been published after converting to digital radiography. One reason may be a belief that rejects have been eliminated with digitalization. To measure the extension of deleted images in direct digital radiography (DR), in order to assess the rates of rejects and unnecessary imaging and to analyze reasons for deletions, in order to improve the radiological services. All exposed images at two direct digital laboratories at a hospital in Norway were reviewed in January 2014. Type of examination, number of exposed images, and number of deleted images were registered. Each deleted image was analyzed separately and the reason for deleting the image was recorded. Out of 5417 exposed images, 596 were deleted, giving a deletion rate of 11%. A total of 51.3% were deleted due to positioning errors and 31.0% due to error in centering. The examinations with the highest percentage of deleted images were the knee, hip, and ankle, 20.6%, 18.5%, and 13.8% respectively. The reject rate is at least as high as the deletion rate and is comparable with previous film-based imaging systems. The reasons for rejection are quite different in digital systems. This falsifies the hypothesis that digitalization would eliminates rejects. A deleted image does not contribute to diagnostics, and therefore is an unnecessary image. Hence, the high rates of deleted images have implications for management, training, education, as well as for quality.

  10. Wavelet transform based watermark for digital images.

    PubMed

    Xia, X G; Boncelet, C; Arce, G

    1998-12-07

    In this paper, we introduce a new multiresolution watermarking method for digital images. The method is based on the discrete wavelet transform (DWT). Pseudo-random codes are added to the large coefficients at the high and middle frequency bands of the DWT of an image. It is shown that this method is more robust to proposed methods to some common image distortions, such as the wavelet transform based image compression, image rescaling/stretching and image halftoning. Moreover, the method is hierarchical.

  11. The magic of image processing

    NASA Astrophysics Data System (ADS)

    Sulentic, J. W.

    1984-05-01

    Digital technology has been used to improve enhancement techniques in astronomical image processing. Continuous tone variations in photographs are assigned density number (DN) values which are arranged in an array. DN locations are processed by computer and turned into pixels which form a reconstruction of the original scene on a television monitor. Digitized data can be manipulated to enhance contrast and filter out gross patterns of light and dark which obscure small scale features. Separate black and white frames exposed at different wavelengths can be digitized and processed individually, then recombined to produce a final image in color. Several examples of the use of the technique are provided, including photographs of spiral galaxy M33; four galaxies in Coma Berenices (NGC 4169, 4173, 4174, and 4175); and Stephens Quintet.

  12. Could digital imaging be an alternative for digital colorimeters?

    PubMed

    Caglar, Alper; Yamanel, Kivanc; Gulsahi, Kamran; Bagis, Bora; Ozcan, Mutlu

    2010-12-01

    This study evaluated the colour parameters of composite and ceramic shade guides determined using a colorimeter and digital imaging method with illuminants at different colour temperatures. Two different resin composite shade guides, namely Charisma (Heraeus Kulzer) and Premise (Kerr Corporation), and two different ceramic shade guides, Vita Lumin Vacuum (VITA Zahnfabrik) and Noritake (Noritake Co.), were evaluated at three different colour temperatures (2,700 K, 2,700-6,500 K, and 6500 K) of illuminants. Ten shade tabs were selected (A1, A2, A3, A3,5, A4, B1, B2, B3, C2 and C3) from each shade guide. CIE Lab values were obtained using digital imaging and a colorimeter (ShadeEye NCC Dental Chroma Meter, Shofu Inc.). The data were analysed using two-way ANOVA, and Pearson's correlation. While mean L* values of both composite and ceramic shade guides were not affected from the colour temperature, L* values obtained with the colorimeter showed significantly lower values than those of the digital imaging (p < 0.01). At combined 2,700-6500 K colour temperature, the means of a* values obtained from colorimeter and digital imaging did not show significant differences (p > 0.05). For both composite and ceramic shade guides, L* and b* values obtained from colorimeter and digital imaging method presented a high level of correlation. High-level correlations were also acquired for a* values in all shade guides except for the Charisma composite shade guide. Digital imaging method could be an alternative for the colorimeters unless the proper object-camera distance, digital camera settings and suitable illumination conditions could be supplied. However, variations in shade guides, especially for composites, may affect the correlation.

  13. C language algorithms for digital signal processing

    SciTech Connect

    Embree, P.M.; Kimble, B.

    1991-01-01

    The use of the C programming language to construct digital signal-processing (DSP) algorithms for operation on high-performance personal computers is described in a textbook for engineering students. Chapters are devoted to the fundamental principles of DSP, basic C programming techniques, user-interface and disk-storage routines, filtering routines, discrete Fourier transforms, matrix and vector routines, and image-processing routines. Also included is a floppy disk containing a library of standard C mathematics, character-string, memory-allocation, and I/O functions; a library of DSP functions; and several sample DSP programs. 83 refs.

  14. Reliability-guided digital image correlation for image deformation measurement

    SciTech Connect

    Pan Bing

    2009-03-10

    A universally applicable reliability-guided digital image correlation (DIC) method is proposed for reliable image deformation measurement. The zero-mean normalized cross correlation (ZNCC) coefficient is used to identify the reliability of the point computed. The correlation calculation begins with a seed point and is then guided by the ZNCC coefficient. That means the neighbors of the point with the highest ZNCC coefficient in a queue for computed points will be processed first. Thus the calculation path is always along the most reliable direction, and possible error propagation of the conventional DIC method can be avoided. The proposed novel DIC method is universally applicable to the images with shadows, discontinuous areas, and deformation discontinuity. Two image pairs were used to evaluate the performance of the proposed technique, and the successful results clearly demonstrate its robustness and effectiveness.

  15. Study of digital mammographic equipments by phantom image quality.

    PubMed

    Mayo, P; Rodenas, F; Verdú, G; Campayo, J M; Villaescusa, J I

    2006-01-01

    Nowadays, the digital radiographic equipments are replacing the traditional film-screen equipments and it is necessary to update the parameters to guarantee the quality of the process. Contrast-detail phantoms are applied to digital radiography to study the threshold contrast-detail sensitivity at operation conditions of the equipment. The phantom that is studied in this work is CDMAM 3.4. One of the most extended indexes to measure the image quality in an objective way is the image quality figure (IQF). The aim of this work is to study the image quality of different images contrast-detail phantom CDMAM 3.4, carrying out the automatic detection of the contrast-detail combination and to establish a parameter which characterize in an objective way the mammographic image quality. This is useful to compare images obtained at different digital mammographic equipments to study the functioning of the equipments that facilitates the evaluation of image contrast and detail resolution.

  16. Panning artifacts in digital pathology images

    NASA Astrophysics Data System (ADS)

    Avanaki, Ali R. N.; Lanciault, Christian; Espig, Kathryn S.; Xthona, Albert; Kimpe, Tom R. L.

    2017-03-01

    In making a pathologic diagnosis, a pathologist uses cognitive processes: perception, attention, memory, and search (Pena and Andrade-Filho, 2009). Typically, this involves focus while panning from one region of a slide to another, using either a microscope in a traditional workflow or software program and display in a digital pathology workflow (DICOM Standard Committee, 2010). We theorize that during panning operation, the pathologist receives information important to diagnosis efficiency and/or correctness. As compared to an optical microscope, panning in a digital pathology image involves some visual artifacts due to the following: (i) the frame rate is finite; (ii) time varying visual signals are reconstructed using imperfect zero-order hold. Specifically, after pixel's digital drive is changed, it takes time for a pixel to emit the expected amount of light. Previous work suggests that 49% of navigation is conducted in low-power/overview with digital pathology (Molin et al., 2015), but the influence of display factors has not been measured. We conducted a reader study to establish a relationship between display frame rate, panel response time, and threshold panning speed (above which the artifacts become noticeable). Our results suggest visual tasks that involve tissue structure are more impacted by the simulated panning artifacts than those that only involve color (e.g., staining intensity estimation), and that the panning artifacts versus normalized panning speed has a peak behavior which is surprising and may change for a diagnostic task. This is work in progress and our final findings should be considered in designing future digital pathology systems.

  17. Digital techniques for processing Landsat imagery

    NASA Technical Reports Server (NTRS)

    Green, W. B.

    1978-01-01

    An overview of the basic techniques used to process Landsat images with a digital computer, and the VICAR image processing software developed at JPL and available to users through the NASA sponsored COSMIC computer program distribution center is presented. Examples of subjective processing performed to improve the information display for the human observer, such as contrast enhancement, pseudocolor display and band rationing, and of quantitative processing using mathematical models, such as classification based on multispectral signatures of different areas within a given scene and geometric transformation of imagery into standard mapping projections are given. Examples are illustrated by Landsat scenes of the Andes mountains and Altyn-Tagh fault zone in China before and after contrast enhancement and classification of land use in Portland, Oregon. The VICAR image processing software system which consists of a language translator that simplifies execution of image processing programs and provides a general purpose format so that imagery from a variety of sources can be processed by the same basic set of general applications programs is described.

  18. Image processing in optical astronomy

    NASA Technical Reports Server (NTRS)

    Lorre, Jean J.

    1988-01-01

    Successful efforts to enhance optical-astronomy images through digital processing often exploit such 'weaknesses' of the image as the objects' near-symmetry, their preferred directionality, or a differentiation in spatial frequency between the object or objects and superimposed clutter. Attention is presently given to the calibration of a camera prior to astronomical data-acquisition, methods for the enhancement of faint surface brightness features, automated target detection and extraction techniques, the importance of the geometric transformations of digital imagery, the preparation of two-dimensional histograms, and the application of polarization.

  19. Refined measurement of digital image texture loss

    NASA Astrophysics Data System (ADS)

    Burns, Peter D.

    2013-01-01

    Image texture is the term given to the information-bearing fluctuations such as those for skin, grass and fabrics. Since image processing aimed at reducing unwanted fluctuations (noise are other artifacts) can also remove important texture, good product design requires a balance between the two. The texture-loss MTF method, currently under international standards development, is aimed at the evaluation of digital and mobile-telephone cameras for capture of image texture. The method uses image fields of pseudo-random objects, such as overlapping disks, often referred to as `dead-leaves' targets. The analysis of these target images is based on noise-power spectrum (NPS) measurements, which are subject to estimation error. We describe a simple method for compensation of non-stationary image statistics, aimed at improving practical NPS estimates. A benign two-dimensional linear function (plane) is fit to the data and subtracted. This method was implemented and results were compared with those without compensation. The adapted analysis method resulted in reduced NPS and MTF measurement variation (20%) and low-frequency bias error. This is a particular advantage at low spatial frequencies, where texture-MTF scaling is performed. We conclude that simple trend removal should be used.

  20. Digital computer processing of X-ray photos

    NASA Technical Reports Server (NTRS)

    Nathan, R.; Selzer, R. H.

    1967-01-01

    Digital computers correct various distortions in medical and biological photographs. One of the principal methods of computer enhancement involves the use of a two-dimensional digital filter to modify the frequency spectrum of the picture. Another computer processing method is image subtraction.

  1. Detection of breast cancer by soft-copy reading of digital mammograms: comparison between a routine image-processing parameter and high-contrast parameters.

    PubMed

    Kamitani, Takeshi; Yabuuchi, Hidetake; Soeda, Hiroyasu; Matsuo, Yoshio; Okafuji, Takashi; Sakai, Shuji; Setoguchi, Taro; Hatakenaka, Masamitsu; Ishii, Nobuhide; Honda, Hiroshi

    2010-02-01

    Recent studies have reported the clinical usefulness of the soft-copy reading of mammograms. However, image-processing parameters for soft-copy reading of digital mammograms have not been established. To compare observer performance in detecting breast cancer by soft-copy reading of digital mammograms using a routine image-processing parameter versus each of several high-contrast parameters. The mammograms of 154 breasts, including 48 abnormal breasts with breast cancer and 106 normal breasts, were examined. Cancers were classified into 34 mass-dominant cancers, 11 microcalcification-dominant cancers, two cancers showing only architectural distortion, and one cancer without abnormal findings. All mammograms were performed using a computed radiography (CR) system. Each image was processed using GA (1.2), which was the contrast parameter recommended by the manufacturer for hard-copy film, GA (1.4), GA (1.6), and GA (1.8). These images were displayed on 5-megapixel (M) liquid-crystal display monitors. Five experienced radiologists classified them into BI-RADS category 1-2 or 3-5, and were also asked to rate the images on a scale of 0 to 100 for the likelihood of the presence of masses and microcalcifications in each breast. In mass-dominant cancers of dense breast tissue, the mean sensitivities of GA (1.2), GA (1.4), GA (1.6), and GA (1.8) were 32.7, 38.2, 36.4, and 40.0, and the A(Z) values were 0.67, 0.73, 0.71, and 0.73, respectively; in microcalcification-dominant cancers, the mean sensitivities were 80.0, 74.5, 80.0, and 78.2, respectively; however, there were no significant differences among them. High-contrast parameters tended to show relatively high sensitivity and A(Z) values in the detection of masses in dense breast tissue, but relatively low sensitivity for microcalcifications.

  2. Linear Algebra and Image Processing

    ERIC Educational Resources Information Center

    Allali, Mohamed

    2010-01-01

    We use the computing technology digital image processing (DIP) to enhance the teaching of linear algebra so as to make the course more visual and interesting. Certainly, this visual approach by using technology to link linear algebra to DIP is interesting and unexpected to both students as well as many faculty. (Contains 2 tables and 11 figures.)

  3. Linear algebra and image processing

    NASA Astrophysics Data System (ADS)

    Allali, Mohamed

    2010-09-01

    We use the computing technology digital image processing (DIP) to enhance the teaching of linear algebra so as to make the course more visual and interesting. Certainly, this visual approach by using technology to link linear algebra to DIP is interesting and unexpected to both students as well as many faculty.

  4. Linear Algebra and Image Processing

    ERIC Educational Resources Information Center

    Allali, Mohamed

    2010-01-01

    We use the computing technology digital image processing (DIP) to enhance the teaching of linear algebra so as to make the course more visual and interesting. Certainly, this visual approach by using technology to link linear algebra to DIP is interesting and unexpected to both students as well as many faculty. (Contains 2 tables and 11 figures.)

  5. Digital imaging in remote diagnosis of burns.

    PubMed

    Roa, L; Gómez-Cía, T; Acha, B; Serrano, C

    1999-11-01

    Images are capable of giving an accurate representation of skin color and have been used extensively in teaching about and researching burn therapy. The advance from analogue to digital imaging allows the remote transmission of the clinical information contained in the digital image of a burn, using a suitable system. The large size of these image files reduces transmission speed and makes data compression desirable. Compression, by means of the JPEG algorithm, of up to 50 times the original size of 38 digital images of burns suffered by 22 consecutive patients did not lessen its great usefulness in determining the depth of burn injuries, according to a group of experts in burn care. The success rate was close to 90%, both for non-compressed images in original BMP format (mean size:1500 Kb) and for compressed images with a Q index of 50 (30 Kb files), when compared with the clinical diagnoses confirmed one week after the accident.

  6. The use of digital images in pathology.

    PubMed

    Furness, P N

    1997-11-01

    Digital images are routinely used by the publishing industry, but most diagnostic pathologists are unfamiliar with the technology and its possibilities. This review aims to explain the basic principles of digital image acquisition, storage, manipulation and use, and the possibilities provided not only in research, but also in teaching and in routine diagnostic pathology. Images of natural objects are usually expressed digitally as 'bitmaps'--rectilinear arrays of small dots. The size of each dot can vary, but so can its information content in terms, for example, of colour, greyscale or opacity. Various file formats and compression algorithms are available. Video cameras connected to microscopes are familiar to most pathologists; video images can be converted directly to a digital form by a suitably equipped computer. Digital cameras and scanners are alternative acquisition tools of relevance to pathologists. Once acquired, a digital image can easily be subjected to the digital equivalent of any conventional darkroom manipulation and modern software allows much more flexibility, to such an extent that a new tool for scientific fraud has been created. For research, image enhancement and analysis is an increasingly powerful and affordable tool. Morphometric measurements are, after many predictions, at last beginning to be part of the toolkit of the diagnostic pathologist. In teaching, the potential to create dramatic yet informative presentations is demonstrated daily by the publishing industry; such methods are readily applicable to the classroom. The combination of digital images and the Internet raises many possibilities; for example, instead of seeking one expert diagnostic opinion, one could simultaneously seek the opinion of many, all around the globe. It is inevitable that in the coming years the use of digital images will spread from the laboratory to the medical curriculum and to the whole of diagnostic pathology.

  7. Invited article: Digital beam-forming imaging riometer systems.

    PubMed

    Honary, Farideh; Marple, Steve R; Barratt, Keith; Chapman, Peter; Grill, Martin; Nielsen, Erling

    2011-03-01

    The design and operation of a new generation of digital imaging riometer systems developed by Lancaster University are presented. In the heart of the digital imaging riometer is a field-programmable gate array (FPGA), which is used for the digital signal processing and digital beam forming, completely replacing the analog Butler matrices which have been used in previous designs. The reconfigurable nature of the FPGA has been exploited to produce tools for remote system testing and diagnosis which have proven extremely useful for operation in remote locations such as the Arctic and Antarctic. Different FPGA programs enable different instrument configurations, including a 4 × 4 antenna filled array (producing 4 × 4 beams), an 8 × 8 antenna filled array (producing 7 × 7 beams), and a Mills cross system utilizing 63 antennas producing 556 usable beams. The concept of using a Mills cross antenna array for riometry has been successfully demonstrated for the first time. The digital beam forming has been validated by comparing the received signal power from cosmic radio sources with results predicted from the theoretical beam radiation pattern. The performances of four digital imaging riometer systems are compared against each other and a traditional imaging riometer utilizing analog Butler matrices. The comparison shows that digital imaging riometer systems, with independent receivers for each antenna, can obtain much better measurement precision for filled arrays or much higher spatial resolution for the Mills cross configuration when compared to existing imaging riometer systems.

  8. Digital Imaging and Conservation: Model Guidelines.

    ERIC Educational Resources Information Center

    Dean, John F.

    2003-01-01

    Examines the intersection of conservation and digital imaging based on guidelines at the Cornell University (Ithaca, NY) library. Discusses the digitization of artifacts; assessing the condition prior to scanning; scanning considerations, including temperature and humidity, lighting, and security; stable storage of artifacts after scanning; and…

  9. Digital Imaging and Conservation: Model Guidelines.

    ERIC Educational Resources Information Center

    Dean, John F.

    2003-01-01

    Examines the intersection of conservation and digital imaging based on guidelines at the Cornell University (Ithaca, NY) library. Discusses the digitization of artifacts; assessing the condition prior to scanning; scanning considerations, including temperature and humidity, lighting, and security; stable storage of artifacts after scanning; and…

  10. Study of the temporal evolution of Whitening Teeth immersed in Peroxide of hydrogen (H2O2) Using Digital Image Processing

    NASA Astrophysics Data System (ADS)

    Díaz, L.; Morales, Y.; Torres, C.

    2015-01-01

    The esthetic dentistry reference in our society is determined by several factors, including one that produces more dissatisfaction is abnormal tooth color or that does not meet the patient's expectations. For this reason it has been designed and implemented an algorithm in MATLAB that captures, digitizes, pre-processing and analyzed dental imaging by allowing to evaluate the degree of bleaching caused by the use of peroxide of hidrogen. The samples analyzed were human teeth extracted, which were subjected to different concentrations of peroxide of hidrogen and see if they can teeth whitening when using these products, was used different concentrations and intervals of time to analysis or study of the whitening of the teeth with the hydrogen peroxide.

  11. The Challenge of Digital Imaging Technologies: A Practical View of the Future.

    ERIC Educational Resources Information Center

    Hamber, Anthony

    1994-01-01

    Discusses digital imaging technologies. Topics include information technology; reprographics; scientific imaging processing; political considerations of telecommunications and the information superhighway; digital cameras; slide and transparency scanners; desktop prepress processing; digital proofing devices; direct-to-plate and direct-to-press…

  12. Image enhancement of digital periapical radiographs according to diagnostic tasks

    PubMed Central

    Choi, Jin-Woo; Han, Won-Jeong

    2014-01-01

    Purpose This study was performed to investigate the effect of image enhancement of periapical radiographs according to the diagnostic task. Materials and Methods Eighty digital intraoral radiographs were obtained from patients and classified into four groups according to the diagnostic tasks of dental caries, periodontal diseases, periapical lesions, and endodontic files. All images were enhanced differently by using five processing techniques. Three radiologists blindly compared the subjective image quality of the original images and the processed images using a 5-point scale. Results There were significant differences between the image quality of the processed images and that of the original images (P<0.01) in all the diagnostic task groups. Processing techniques showed significantly different efficacy according to the diagnostic task (P<0.01). Conclusion Image enhancement affects the image quality differently depending on the diagnostic task. And the use of optimal parameters is important for each diagnostic task. PMID:24701456

  13. Image enhancement of digital periapical radiographs according to diagnostic tasks.

    PubMed

    Choi, Jin-Woo; Han, Won-Jeong; Kim, Eun-Kyung

    2014-03-01

    This study was performed to investigate the effect of image enhancement of periapical radiographs according to the diagnostic task. Eighty digital intraoral radiographs were obtained from patients and classified into four groups according to the diagnostic tasks of dental caries, periodontal diseases, periapical lesions, and endodontic files. All images were enhanced differently by using five processing techniques. Three radiologists blindly compared the subjective image quality of the original images and the processed images using a 5-point scale. There were significant differences between the image quality of the processed images and that of the original images (P<0.01) in all the diagnostic task groups. Processing techniques showed significantly different efficacy according to the diagnostic task (P<0.01). Image enhancement affects the image quality differently depending on the diagnostic task. And the use of optimal parameters is important for each diagnostic task.

  14. Effectiveness of Digital Pulse Processing Using a Slow Waveform Digitizer

    NASA Astrophysics Data System (ADS)

    Anthony, Adam; Ahmed, Mohammad; Sikora, Mark

    2016-09-01

    Using a waveform digitizer, one can replace nearly all of the analog electronics typically involved in processing pulses from a detector by directly digitizing the signal and processing it using digital algorithms. Algorithms for timing filter amplification, constant fraction discrimination, trapezoidal pulse shaping, peak sensing with pileup rejection, and charge integration were developed and implemented. The algorithms and a digitizer with a sampling rate of 62.5 MS/sec were used to calculate the energy and timing resolution of a various scintillation and solid state detectors. These resolutions are compared against both a traditional charge to digital (QDC), and the analog to digital (ADC) data acquisition setup in use at the High Intensity Gamma Source at Duke University. Preliminary results are presented.

  15. Development of standard digital images for pneumoconiosis.

    PubMed

    Lee, Won-Jeong; Choi, Byung-Soon; Kim, Sung Jin; Park, Choong-Ki; Park, Jai-Soung; Tae, Seok; Hering, Kurt Georg

    2011-11-01

    We developed the standard digital images (SDIs) to be used in the classification and recognition of pneumoconiosis. From July 3, 2006 through August 31, 2007, 531 retired male workers exposed to inorganic dust were examined by digital (DR) and analog radiography (AR) on the same day, after being approved by our institutional review board and obtaining informed consent from all participants. All images were twice classified according to the International Labour Office (ILO) 2000 guidelines with reference to ILO standard analog radiographs (SARs) by four chest radiologists. After consensus reading on 349 digital images matched with the first selected analog images, 120 digital images were selected as the SDIs that considered the distribution of pneumoconiosis findings. Images with profusion category 0/1, 1, 2, and 3 were 12, 50, 40, and 15, respectively, and a large opacity were in 43 images (A = 20, B = 22, C = 1). Among pleural abnormality, costophrenic angle obliteration, pleural plaque and thickening were in 11 (9.2%), 31 (25.8%), and 9 (7.5%) images, respectively. Twenty-one of 29 symbols were present except cp, ef, ho, id, me, pa, ra, and rp. A set of 120 SDIs had more various pneumoconiosis findings than ILO SARs that were developed from adequate methods. It can be used as digital reference images for the recognition and classification of pneumoconiosis.

  16. Digital Image Analysis for DETCHIP® Code Determination

    PubMed Central

    Lyon, Marcus; Wilson, Mark V.; Rouhier, Kerry A.; Symonsbergen, David J.; Bastola, Kiran; Thapa, Ishwor; Holmes, Andrea E.

    2013-01-01

    DETECHIP® is a molecular sensing array used for identification of a large variety of substances. Previous methodology for the analysis of DETECHIP® used human vision to distinguish color changes induced by the presence of the analyte of interest. This paper describes several analysis techniques using digital images of DETECHIP®. Both a digital camera and flatbed desktop photo scanner were used to obtain Jpeg images. Color information within these digital images was obtained through the measurement of red-green-blue (RGB) values using software such as GIMP, Photoshop and ImageJ. Several different techniques were used to evaluate these color changes. It was determined that the flatbed scanner produced in the clearest and more reproducible images. Furthermore, codes obtained using a macro written for use within ImageJ showed improved consistency versus pervious methods. PMID:25267940

  17. Quantitative determination of some food dyes using digital processing of images obtained by thin-layer chromatography.

    PubMed

    Soponar, Florin; Moţ, Augustin Cătălin; Sârbu, Costel

    2008-04-25

    A high-performance thin-layer chromatographic method combined with image processing of scanned chromatograms was developed for the determination of some food dyes (tartrazine, azorubine and Sunset Yellow) in different products. Porous silica gel with 3-aminopropyl functional groups attached to the matrix was used as stationary phase and a mixture of isopropanol, diethyl ether and ammonia (2:2:1, v/v/v) formed the mobile phase. Quantitative evaluation was performed using special-purpose software. The linearity of the analytical procedure was sustained by the numerical parameters such as correlation coefficient (0.9952-0.9980) and standard error of determination (0.03-0.20). The limits of detection were found to be within the range of 5.21-9.34 ng/spot, and the limits of quantification between 10.21 and 18.09 ng/spot. Recovery studies performed on two levels of concentration gave values between 96.39 and 102.76%. These results show that the regression approach provides rigorous and realistic detection and quantification limits and as a consequence can be routinely applied to other analytical systems. This method does not require expensive analytical instruments compared with classical densitometry and provides a reliable quantitative evaluation with minimum of time.

  18. Impact of digital image manipulation in cytology.

    PubMed

    Pinco, Jeffery; Goulart, Robert A; Otis, Christopher N; Garb, Jane; Pantanowitz, Liron

    2009-01-01

    Digital images have become an important component of cytology practice. They are used in telecytology, automated screening, educational material, and Web sites and have potential for use in proficiency testing. However, there has been no formal evaluation to date to determine if digital image manipulation (intentional or unintentional) can affect their interpretation. To investigate whether alteration of digital cytology images affects diagnosis. Acquired digital images of ThinPrep Papanicolaou test slides were manipulated (rotated 90 degrees and brightness, contrast, red-green-blue color, and luminosity adjusted) using Photoshop. A test composed of these altered images, along with their original (unaltered) image and exact duplicates was given to 22 cytologists (13 cytotechnologists, 8 cytopathologists, and 1 fellow). All images were rated as negative, atypical (atypical squamous cells of undetermined significance), low-grade squamous intraepithelial lesion, high-grade squamous intraepithelial lesion, or positive for cancer. Weighted kappa and heterogeneity chi(2) statistics were used to measure levels of agreement and assess concordance between groups. The level of agreement for identical duplicate images was excellent (kappa = 0.81), compared with the poor agreement for manipulated image pairs (kappa = 0.21), a statistically significant difference (P < .001). For all altered image types agreement was poor. There was no significant difference between cytotechnologists and cytopathologists in level of agreement (P = .56). Manipulation of a Papanicolaou test digital image, irrespective of the specific category of cytologic material photographed, significantly affects its interpretation by both cytotechnologists and cytopathologists. This suggests that care needs to be taken when digital cytology images are used, to specifically ensure that their alteration does not affect diagnosis.

  19. The influence of software filtering in digital mammography image quality

    NASA Astrophysics Data System (ADS)

    Michail, C.; Spyropoulou, V.; Kalyvas, N.; Valais, I.; Dimitropoulos, N.; Fountos, G.; Kandarakis, I.; Panayiotakis, G.

    2009-05-01

    Breast cancer is one of the most frequently diagnosed cancers among women. Several techniques have been developed to help in the early detection of breast cancer such as conventional and digital x-ray mammography, positron and single-photon emission mammography, etc. A key advantage in digital mammography is that images can be manipulated as simple computer image files. Thus non-dedicated commercially available image manipulation software can be employed to process and store the images. The image processing tools of the Photoshop (CS 2) software usually incorporate digital filters which may be used to reduce image noise, enhance contrast and increase spatial resolution. However, improving an image quality parameter may result in degradation of another. The aim of this work was to investigate the influence of three sharpening filters, named hereafter sharpen, sharpen more and sharpen edges on image resolution and noise. Image resolution was assessed by means of the Modulation Transfer Function (MTF).In conclusion it was found that the correct use of commercial non-dedicated software on digital mammograms may improve some aspects of image quality.

  20. Phase in Optical Image Processing

    NASA Astrophysics Data System (ADS)

    Naughton, Thomas J.

    2010-04-01

    The use of phase has a long standing history in optical image processing, with early milestones being in the field of pattern recognition, such as VanderLugt's practical construction technique for matched filters, and (implicitly) Goodman's joint Fourier transform correlator. In recent years, the flexibility afforded by phase-only spatial light modulators and digital holography, for example, has enabled many processing techniques based on the explicit encoding and decoding of phase. One application area concerns efficient numerical computations. Pushing phase measurement to its physical limits, designs employing the physical properties of phase have ranged from the sensible to the wonderful, in some cases making computationally easy problems easier to solve and in other cases addressing mathematics' most challenging computationally hard problems. Another application area is optical image encryption, in which, typically, a phase mask modulates the fractional Fourier transformed coefficients of a perturbed input image, and the phase of the inverse transform is then sensed as the encrypted image. The inherent linearity that makes the system so elegant mitigates against its use as an effective encryption technique, but we show how a combination of optical and digital techniques can restore confidence in that security. We conclude with the concept of digital hologram image processing, and applications of same that are uniquely suited to optical implementation, where the processing, recognition, or encryption step operates on full field information, such as that emanating from a coherently illuminated real-world three-dimensional object.

  1. Why optics students should take digital signal processing courses and why digital signal processing students should take optics courses

    NASA Astrophysics Data System (ADS)

    Cathey, W. Thomas, Jr.

    2000-06-01

    This paper is based on the claim that future major contributions in the field of imaging systems will be made by those who have a background in both optics and digital signal processing. As the introduction of Fourier transforms and linear systems theory to optics had a major impact on the design of hybrid optical/digital imaging systems, the introduction of digital signal processing into optics programs will have a major impact. Examples are given of new hybrid imaging systems that have unique performance. By jointly designing the optics and the signal processing in a digital camera, a new paradigm arises where aberration balancing takes into consideration not only the number of surfaces and indices of refraction, but also the processing capability.

  2. Digital hardware and computer system for a digital image recorder.

    NASA Technical Reports Server (NTRS)

    Dennison, E. W.

    1973-01-01

    Description of the digital memory and related computer system used at the Palomar Mountain Observatory. The memory was designed to have a large number of pixels, a high capacity for each pixel, and fast access for use with a variety of image sensors. As an image integration and storage device, this memory is shown to possess ideal properties, namely, it is strictly linear, has a wide dynamic range, and the image does not deteriorate with time. The observer has a visual display which enables him to monitor the image as it is being integrated.-

  3. Digital hardware and computer system for a digital image recorder.

    NASA Technical Reports Server (NTRS)

    Dennison, E. W.

    1973-01-01

    Description of the digital memory and related computer system used at the Palomar Mountain Observatory. The memory was designed to have a large number of pixels, a high capacity for each pixel, and fast access for use with a variety of image sensors. As an image integration and storage device, this memory is shown to possess ideal properties, namely, it is strictly linear, has a wide dynamic range, and the image does not deteriorate with time. The observer has a visual display which enables him to monitor the image as it is being integrated.-

  4. Digital image centering. II. [for astronomical photography

    NASA Technical Reports Server (NTRS)

    Auer, L. H.; Van Altena, W. F.

    1978-01-01

    Digital image centering algorithms were compared in a test involving microdensitometer raster scans of a refractor parallax series consisting of 22 stars on 26 plates. The highest accuracy in determining stellar image positions was provided by an algorithm which involved fitting of a symmetric Gaussian curve and a flat background to the image marginal density distributions. Algorithms involving transmission marginals instead of density marginals were found to be less accurate. The repeatability and computational efficiency of the digital image centering technique were also studied.

  5. Cell imaging techniques based on digital image plane holography

    NASA Astrophysics Data System (ADS)

    Chen, Zhaoji; Gong, Wendi; Liu, Feifei; Wang, Huaying

    2010-11-01

    This paper has further studied the implementation methods and recording conditions of digital microscopic image plane holography (DMIPH). Two optical systems of DMIPH were built: one is recording hologram by using plane waves as reference light, the other is recording hologram by spherical reference light. Breast cancer cells and USAF resolution test target is used as tested samples in the experiment. Then the intensity distribution and three-dimensional shape information of the cells are got accurately. The experiment results show that DMIPH avoids the process of finding recording distance by using auto-focusing approach. The recording and reconstruction process of DMIPH is simple. Therefore DMIPH can be applied to the microscopic imaging of cells more effectively.

  6. Digital processing system for developing countries

    NASA Technical Reports Server (NTRS)

    Nanayakkara, C.; Wagner, H.

    1977-01-01

    An effort was undertaken to perform simple digital processing tasks using pre-existing general purpose digital computers. An experimental software package, LIGMALS, was obtained and modified for this purpose. The resulting software permits basic processing tasks to be performed including level slicing, gray mapping and ratio processing. The experience gained in this project indicates a possible direction which may be used by other developing countries to obtain digital processing capabilities.

  7. Problems by Assessment of Accuracy at Processing Joint Rows of Digitized Astronomical Images Obtained with Different Instruments

    NASA Astrophysics Data System (ADS)

    Kazantseva, L.

    2016-09-01

    Current methods for determining the astrometry positions of digitized photographic plates have difficulty for correctly using data from different telescopes. Factors such as scale of a plate, exposure duration, size of the plate and its quality, affect the accuracy of the results. Scanner options add their mistakes. Often, it is important to get results in prolonged time period. In such cases, we use observational data that were obtained using different telescopes. Then there is the need to balance the various data accuracy. The report provides a methodical approach. The method has been tested for some standard star fields.

  8. Comparison of rotation algorithms for digital images

    NASA Astrophysics Data System (ADS)

    Starovoitov, Valery V.; Samal, Dmitry

    1999-09-01

    The paper presents a comparative study of several algorithms developed for digital image rotation. No losing generality we studied gray scale images. We have tested methods preserving gray values of the original images, performing some interpolation and two procedures implemented into the Corel Photo-paint and Adobe Photoshop soft packages. By the similar way methods for rotation of color images may be evaluated also.

  9. Sgraffito simulation through image processing

    NASA Astrophysics Data System (ADS)

    Guerrero, Roberto A.; Serón Arbeloa, Francisco J.

    2011-10-01

    This paper presents a tool for simulating the traditional Sgraffito technique through digital image processing. The tool is based on a digital image pile and a set of attributes recovered from the image at the bottom of the pile using the Streit and Buchanan multiresolution image pyramid. This technique tries to preserve the principles of artistic composition by means of the attributes of color, luminance and shape recovered from the foundation image. A couple of simulated scratching objects will establish how the recovered attributes have to be painted. Different attributes can be painted by using different scratching primitives. The resulting image will be a colorimetric composition reached from the image on the top of the pile, the color of the images revealed by scratching and the inner characteristics of each scratching primitive. The technique combines elements of image processing, art and computer graphics allowing users to make their own free compositions and providing a means for the development of visual communication skills within the user-observer relationship. The technique enables the application of the given concepts in non artistic fields with specific subject tools.

  10. Computer image processing: Geologic applications

    NASA Technical Reports Server (NTRS)

    Abrams, M. J.

    1978-01-01

    Computer image processing of digital data was performed to support several geological studies. The specific goals were to: (1) relate the mineral content to the spectral reflectance of certain geologic materials, (2) determine the influence of environmental factors, such as atmosphere and vegetation, and (3) improve image processing techniques. For detection of spectral differences related to mineralogy, the technique of band ratioing was found to be the most useful. The influence of atmospheric scattering and methods to correct for the scattering were also studied. Two techniques were used to correct for atmospheric effects: (1) dark object subtraction, (2) normalization of use of ground spectral measurements. Of the two, the first technique proved to be the most successful for removing the effects of atmospheric scattering. A digital mosaic was produced from two side-lapping LANDSAT frames. The advantages were that the same enhancement algorithm can be applied to both frames, and there is no seam where the two images are joined.

  11. Digital signal processing in microwave radiometers

    NASA Technical Reports Server (NTRS)

    Lawrence, R. W.; Stanley, W. D.; Harrington, R. F.

    1980-01-01

    A microprocessor based digital signal processing unit has been proposed to replace analog sections of a microwave radiometer. A brief introduction to the radiometer system involved and a description of problems encountered in the use of digital techniques in radiometer design are discussed. An analysis of the digital signal processor as part of the radiometer is then presented.

  12. Analysis of radar images by means of digital terrain models

    NASA Technical Reports Server (NTRS)

    Domik, G.; Leberl, F.; Kobrick, M.

    1984-01-01

    It is pointed out that the importance of digital terrain models in the processing, analysis, and interpretation of remote sensing data is increasing. In investigations related to the study of radar images, digital terrain models can have a particular significance, because radar reflection is a function of the terrain characteristics. A procedure for the analysis and interpretation of radar images is discussed. The procedure is based on a utilization of computer simulation which makes it possible to produce simulated radar images on the basis of a digital terrain model. The simulated radar images are used for the geometric and radiometric rectification of real radar images. A description of the employed procedures is provided, and the obtained results are discussed, taking into account a test area in Northern California.

  13. Analysis of radar images by means of digital terrain models

    NASA Technical Reports Server (NTRS)

    Domik, G.; Leberl, F.; Kobrick, M.

    1984-01-01

    It is pointed out that the importance of digital terrain models in the processing, analysis, and interpretation of remote sensing data is increasing. In investigations related to the study of radar images, digital terrain models can have a particular significance, because radar reflection is a function of the terrain characteristics. A procedure for the analysis and interpretation of radar images is discussed. The procedure is based on a utilization of computer simulation which makes it possible to produce simulated radar images on the basis of a digital terrain model. The simulated radar images are used for the geometric and radiometric rectification of real radar images. A description of the employed procedures is provided, and the obtained results are discussed, taking into account a test area in Northern California.

  14. Topics in digital signal processing

    NASA Astrophysics Data System (ADS)

    Narayan, S. S. R.

    Three discrete Fourier transform (DFT) algorithms, namely, the fast Fourier transform algorithm (FFT), the prime factor algorithm (PFA) and the Winograd Fourier transform algorithm (WFTA) are analyzed and compared. A new set of short-length DFT algorithms well-suited for special purpose hardware implementations, employing monolithic multiplier-accumulators and microprocessors, are presented. Architectural considerations in designing DFT processors based on these algorithms are discussed. Efficient hardware structures for implementing the FFT and the PFA are presented. A digital implementation for performing linear-FM (LFM) pulse compression by using bandpass filter banks is presented. The concept of transform domain adaptive filtering is introduced. The DFT and the discrete cosine transform (DFT) domain adaptive filtering algorithm are considered. Applications of these in the areas of speech processing and adaptive line enhancers are discussed. A simple waveform coding algorithm capable of providing good quality speech at about 1.5 bits per sample is presented.

  15. Image microarrays (IMA): Digital pathology's missing tool.

    PubMed

    Hipp, Jason; Cheng, Jerome; Pantanowitz, Liron; Hewitt, Stephen; Yagi, Yukako; Monaco, James; Madabhushi, Anant; Rodriguez-Canales, Jaime; Hanson, Jeffrey; Roy-Chowdhuri, Sinchita; Filie, Armando C; Feldman, Michael D; Tomaszewski, John E; Shih, Natalie Nc; Brodsky, Victor; Giaccone, Giuseppe; Emmert-Buck, Michael R; Balis, Ulysses J

    2011-01-01

    The increasing availability of whole slide imaging (WSI) data sets (digital slides) from glass slides offers new opportunities for the development of computer-aided diagnostic (CAD) algorithms. With the all-digital pathology workflow that these data sets will enable in the near future, literally millions of digital slides will be generated and stored. Consequently, the field in general and pathologists, specifically, will need tools to help extract actionable information from this new and vast collective repository. To address this limitation, we designed and implemented a tool (dCORE) to enable the systematic capture of image tiles with constrained size and resolution that contain desired histopathologic features. In this communication, we describe a user-friendly tool that will enable pathologists to mine digital slides archives to create image microarrays (IMAs). IMAs are to digital slides as tissue microarrays (TMAs) are to cell blocks. Thus, a single digital slide could be transformed into an array of hundreds to thousands of high quality digital images, with each containing key diagnostic morphologies and appropriate controls. Current manual digital image cut-and-paste methods that allow for the creation of a grid of images (such as an IMA) of matching resolutions are tedious. The ability to create IMAs representing hundreds to thousands of vetted morphologic features has numerous applications in education, proficiency testing, consensus case review, and research. Lastly, in a manner analogous to the way conventional TMA technology has significantly accelerated in situ studies of tissue specimens use of IMAs has similar potential to significantly accelerate CAD algorithm development.

  16. Image microarrays (IMA): Digital pathology's missing tool

    PubMed Central

    Hipp, Jason; Cheng, Jerome; Pantanowitz, Liron; Hewitt, Stephen; Yagi, Yukako; Monaco, James; Madabhushi, Anant; Rodriguez-canales, Jaime; Hanson, Jeffrey; Roy-Chowdhuri, Sinchita; Filie, Armando C.; Feldman, Michael D.; Tomaszewski, John E.; Shih, Natalie NC.; Brodsky, Victor; Giaccone, Giuseppe; Emmert-Buck, Michael R.; Balis, Ulysses J.

    2011-01-01

    Introduction: The increasing availability of whole slide imaging (WSI) data sets (digital slides) from glass slides offers new opportunities for the development of computer-aided diagnostic (CAD) algorithms. With the all-digital pathology workflow that these data sets will enable in the near future, literally millions of digital slides will be generated and stored. Consequently, the field in general and pathologists, specifically, will need tools to help extract actionable information from this new and vast collective repository. Methods: To address this limitation, we designed and implemented a tool (dCORE) to enable the systematic capture of image tiles with constrained size and resolution that contain desired histopathologic features. Results: In this communication, we describe a user-friendly tool that will enable pathologists to mine digital slides archives to create image microarrays (IMAs). IMAs are to digital slides as tissue microarrays (TMAs) are to cell blocks. Thus, a single digital slide could be transformed into an array of hundreds to thousands of high quality digital images, with each containing key diagnostic morphologies and appropriate controls. Current manual digital image cut-and-paste methods that allow for the creation of a grid of images (such as an IMA) of matching resolutions are tedious. Conclusion: The ability to create IMAs representing hundreds to thousands of vetted morphologic features has numerous applications in education, proficiency testing, consensus case review, and research. Lastly, in a manner analogous to the way conventional TMA technology has significantly accelerated in situ studies of tissue specimens use of IMAs has similar potential to significantly accelerate CAD algorithm development. PMID:22200030

  17. Image data processing system requirements study. Volume 1: Analysis. [for Earth Resources Survey Program

    NASA Technical Reports Server (NTRS)

    Honikman, T.; Mcmahon, E.; Miller, E.; Pietrzak, L.; Yorsz, W.

    1973-01-01

    Digital image processing, image recorders, high-density digital data recorders, and data system element processing for use in an Earth Resources Survey image data processing system are studied. Loading to various ERS systems is also estimated by simulation.

  18. Numerical suppression of zero-order image in digital holography.

    PubMed

    Chen, Gu-Liang; Lin, Ching-Yang; Kuo, Ming-Kuei; Chang, Chi-Ching

    2007-07-09

    This work describes a novel approach that adopts numerical operation to suppress the zero-order images of reconstruction in digital holography. The entire process needs only one digital hologram and keeps under control the intensity ratio of the object wave to reference wave in recording procedure. Also the performance of numerical suppression is simple and effective by subtracting the numerical generated intensity of the object and reference waves from the digital hologram. The experimental results demonstrate that the zero-order images of reconstruction can be suppressed completely and represents the satisfactory reconstructed image even if the distribution of the object wave is not uniform. Therefore this approach can simplify the procedure of phase-shifting digital holographic-based scheme involving multiple exposures. Moreover, the investigation of performance using the novel suppression approach is presented for proving the practical feasibility.

  19. Using digital image processing to characterize the Campbell-Stokes sunshine recorder and to derive high-temporal resolution direct solar irradiance

    NASA Astrophysics Data System (ADS)

    Sanchez-Romero, A.; González, J. A.; Calbó, J.; Sanchez-Lorenzo, A.

    2014-09-01

    The Campbell-Stokes sunshine recorder (CSSR) has been one of the most commonly used instruments for measuring sunshine duration (SD) through the burn length of a given CSSR card. Many authors have used SD to obtain information about cloudiness and solar radiation (by using Ångström-Prescott type formulas). Contrarily, the burn width has not been used systematically. In principle, the burn width increases for increasing direct beam irradiance. The aim of this research is to show the relationship between burn width and direct solar irradiance (DSI), and to prove whether this relationship depends on the type of CSSR and burning card. A semi-automatic method based on image processing of digital scanned images of burnt cards is presented. With this method, the temporal evolution of the burn width with 1 min resolution can be obtained. From this, SD is easily calculated and compared with the traditional (i.e. visual) determination. The method tends to slightly overestimate SD but the thresholds that are used in the image processing could be adjusted to obtain an unbiased estimation. Regarding the burn width, results show that there is a high correlation between two different models of CSSRs, as well as a strong relationship between burn widths and DSI at a high-temporal resolution. Thus, for example, hourly DSI may be estimated from the burn width with higher accuracy than based on burn length (for one of the CSSR, relative root mean squared error 24 and 30% respectively; mean bias error -0.6 and -30.0 W m-2 respectively). The method offers a practical way to exploit long-term sets of CSSR cards to create long time series of DSI. Since DSI is affected by atmospheric aerosol content, CSSR records may also become a proxy measurement for turbidity and atmospheric aerosol loading.

  20. Using digital image processing to characterize the Campbell-Stokes sunshine recorder and to derive high-temporal resolution direct solar irradiance

    NASA Astrophysics Data System (ADS)

    Sanchez-Romero, A.; González, J. A.; Calbó, J.; Sanchez-Lorenzo, A.

    2015-01-01

    The Campbell-Stokes sunshine recorder (CSSR) has been one of the most commonly used instruments for measuring sunshine duration (SD) through the burn length of a given CSSR card. Many authors have used SD to obtain information about cloudiness and solar radiation (by using Ångström-Prescott type formulas), but the burn width has not been used systematically. In principle, the burn width increases for increasing direct beam irradiance. The aim of this research is to show the relationship between burn width and direct solar irradiance (DSI) and to prove whether this relationship depends on the type of CSSR and burning card. A method of analysis based on image processing of digital scanned images of burned cards is used. With this method, the temporal evolution of the burn width with 1 min resolution can be obtained. From this, SD is easily calculated and compared with the traditional (i.e., visual) determination. The method tends to slightly overestimate SD, but the thresholds that are used in the image processing could be adjusted to obtain an improved estimation. Regarding the burn width, experimental results show that there is a high correlation between two different models of CSSRs, as well as a strong relationship between burn widths and DSI at a high-temporal resolution. Thus, for example, hourly DSI may be estimated from the burn width with higher accuracy than based on burn length (for one of the CSSR, relative root mean squared error is 24 and 30%, respectively; mean bias error is -0.6 and -30.0 W m-2, respectively). The method offers a practical way to exploit long-term sets of CSSR cards to create long time series of DSI. Since DSI is affected by atmospheric aerosol content, CSSR records may also become a proxy measurement for turbidity and atmospheric aerosol loading.

  1. Digital image registration by correlation techniques.

    NASA Technical Reports Server (NTRS)

    Popp, D. J.; Mccormack, D. S.; Lee, G. M.

    1972-01-01

    This study considers the translation problem associated with digital image registration and develops a means for comparing commonly used correlation techniques. Using suitably defined constraints, an optimum and four suboptimum registration techniques are defined and evaluated. A computational comparison is made and Gaussian image statistics are used to compare the selected techniques in terms of radial position location error.

  2. Using ZEMAX Image Analysis and user-defined surfaces for projection lens design and evaluation for Digital Light Processing projection systems

    NASA Astrophysics Data System (ADS)

    Dewald, D. S.

    2000-07-01

    This paper discusses the use of ZEMAX's Image Analysis feature to verify and predict the performance of Digital Light ProcessingTM (DLP) projection-lens designs. The main goals are to visualize the effects of lateral color, axial color, and the remaining Seidel aberrations on the focus of small DLP pixels on the screen in actual use. In many cases there is a discrepancy between what the projector user would define as `good pixel focus' or `sharp focus' and metrics that would determine focus quality or resolution for the lens designer. ZEMAX Image Analysis is a valuable tool for lens design and visualizing lens performance before a prototype lens is built. In addition, the user-defined offset surface is discussed, which was developed to simulate the separate focus of red, green, and blue DMDsTM in three-chip displays. This feature is used to simulate the effect of interchangeable lenses, as each lens has a different axial color characteristic and the depth of field is small, or to verify the compatibility of a lens design on a projector prefocused using a different lens. As display pixel sizes shrink, this simulation technique becomes more useful for evaluating projection lens designs, manufacturing tolerances, and ergonomic concerns during assembly.

  3. Digital image processing for lithological and alteration mapping using SPOT multispectral data: a case study of Pariz area, Kerman Province, Iran

    NASA Astrophysics Data System (ADS)

    Ranjbar, Hojjatollah; Roonwal, Ganpat S.

    2002-01-01

    Tertiary porphyry deposits in Iran are an important source of Cu, Mo and locally Au. Most of the known porphyry Cu deposits are located in the Central Iranian Volcanic Belt(CIVB). Pariz area is located within this belt and is chosen as a test area to evaluate remote sensing data at one such area, and use of these data in exploration of the other parts of CIVB. Eight known mineralization sites were chosen in the area, which are mainly porphyry type. SPOT images in XS mode are used to study geology as well as hydrothermal alteration in the Pariz area, where soil and vegetation cover is substantially poor. Different approaches such as band ratioing, principal component analysis, I-S-H decorrelation processing, digital filtering and hybrid composite were used to enhance the diagnostic features associated with the lithologies as well as the hydrothermal alteration. Color combinations of the principal components, I-S-H transformation and 2/1 ratio have proved to be the best image enhancement techniques for geological studies in such areas. Lineament analysis has shown that the areas with known ore occurrence and the hydrothermally altered areas are closely associated with the higher photolineament factor values. Comparison of geophysical and remote sensing data has shown that there is a good correlation between the airborne geophysical and remote sensing data in the area.

  4. Agricultural inventory capabilities of machine processed LANDSAT digital data

    NASA Technical Reports Server (NTRS)

    Dietrick, D. L.; Fries, R. E.; Egbert, D. D.

    1975-01-01

    Agricultural crop identification and acreage determination analysis of LANDSAT digital data was performed for two study areas. A multispectral image processing and analysis system was utilized to perform the manmachine interactive analysis. The developed techniques yielded crop acreage estimate results with accuracy greater than 90% and as high as 99%. These results are encouraging evidence of agricultural inventory capabilities of machine processed LANDSAT digital data.

  5. TM digital image products for applications. [computer compatible tapes

    NASA Technical Reports Server (NTRS)

    Barker, J. L.; Gunther, F. J.; Abrams, R. B.; Ball, D.

    1984-01-01

    The image characteristics of digital data generated by LANDSAT 4 thematic mapper (TM) are discussed. Digital data from the TM resides in tape files at various stages of image processing. Within each image data file, the image lines are blocked by a factor of either 5 for a computer compatible tape CCT-BT, or 4 for a CCT-AT and CCT-PT; in each format, the image file has a different format. Nominal geometric corrections which provide proper geodetic relationships between different parts of the image are available only for the CCT-PT. It is concluded that detector 3 of band 5 on the TM does not respond; this channel of data needs replacement. The empty bin phenomenon in CCT-AT images results from integer truncations of mixed-mode arithmetric operations.

  6. Multispectral imaging and image processing

    NASA Astrophysics Data System (ADS)

    Klein, Julie

    2014-02-01

    The color accuracy of conventional RGB cameras is not sufficient for many color-critical applications. One of these applications, namely the measurement of color defects in yarns, is why Prof. Til Aach and the Institute of Image Processing and Computer Vision (RWTH Aachen University, Germany) started off with multispectral imaging. The first acquisition device was a camera using a monochrome sensor and seven bandpass color filters positioned sequentially in front of it. The camera allowed sampling the visible wavelength range more accurately and reconstructing the spectra for each acquired image position. An overview will be given over several optical and imaging aspects of the multispectral camera that have been investigated. For instance, optical aberrations caused by filters and camera lens deteriorate the quality of captured multispectral images. The different aberrations were analyzed thoroughly and compensated based on models for the optical elements and the imaging chain by utilizing image processing. With this compensation, geometrical distortions disappear and sharpness is enhanced, without reducing the color accuracy of multispectral images. Strong foundations in multispectral imaging were laid and a fruitful cooperation was initiated with Prof. Bernhard Hill. Current research topics like stereo multispectral imaging and goniometric multispectral measure- ments that are further explored with his expertise will also be presented in this work.

  7. [Effect of digital radiography processing parameters on digital chest radiograph for occupational exposed workers].

    PubMed

    Wang, Xiao-hua; Liu, Dong-sheng; Xuan, Xiao; Kang, Han; Yuan, Hui-shu

    2013-05-01

    To investigate the effect of different processing parameters of digital radiography (DR) on the image quality of digital chest radiograph in dust-exposed workers. One hundred and five dust-exposed workers underwent both high-KV radiography and DR to obtain chest radiographs; the image processing parameters were set by the conventional processing method for digital chest radiograph (method A) and the processing method based on the special requirements of occupational diseases (method B). With the high-KV chest radiograph as the reference, the image qualities at 10 anatomic sites of DR image were graded. The images acquired by DR and high-KV radiography were compared, and the DR images acquired by methods A and B were also compared. For method A, the scores at the 10 anatomic sites of DR image were mostly 0 and +1, accounting for over 88%, and the mean score was 0.23 ∼ 0.65, there was a significant difference between the mean score of DR image and the score of high-KV image (P < 0.001). For method B, the scores at the 10 anatomic sites of DR image were mostly 0, accounting for over 65%, and the mean score was -0.01∼ +0.02 except at the pleura and chest wall; there was no significant difference between the mean score of DR image and the score of high-KV image (P > 0.05). There were significant differences in the scores at the 10 anatomic sites between the DR images acquired by methods A and B (P < 0.01). The DR images acquired based on different processing parameters are different. The quality of DR image acquired by the processing method based on the special requirements of occupational diseases is similar to that of high-KV image at the anatomic sites.

  8. Industrial applications of process imaging and image processing

    NASA Astrophysics Data System (ADS)

    Scott, David M.; Sunshine, Gregg; Rosen, Lou; Jochen, Ed

    2001-02-01

    Process imaging is the art of visualizing events inside closed industrial processes. Image processing is the art of mathematically manipulating digitized images to extract quantitative information about such processes. Ongoing advances in camera and computer technology have made it feasible to apply these abilities to measurement needs in the chemical industry. To illustrate the point, this paper describes several applications developed at DuPont, where a variety of measurements are based on in-line, at-line, and off-line imaging. Application areas include compounding, melt extrusion, crystallization, granulation, media milling, and particle characterization. Polymer compounded with glass fiber is evaluated by a patented radioscopic (real-time X-ray imaging) technique to measure concentration and dispersion uniformity of the glass. Contamination detection in molten polymer (important for extruder operations) is provided by both proprietary and commercial on-line systems. Crystallization in production reactors is monitored using in-line probes and flow cells. Granulation is controlled by at-line measurements of granule size obtained from image processing. Tomographic imaging provides feedback for improved operation of media mills. Finally, particle characterization is provided by a robotic system that measures individual size and shape for thousands of particles without human supervision. Most of these measurements could not be accomplished with other (non-imaging) techniques.

  9. Method of improving a digital image

    NASA Technical Reports Server (NTRS)

    Rahman, Zia-ur (Inventor); Jobson, Daniel J. (Inventor); Woodell, Glenn A. (Inventor)

    1999-01-01

    A method of improving a digital image is provided. The image is initially represented by digital data indexed to represent positions on a display. The digital data is indicative of an intensity value I.sub.i (x,y) for each position (x,y) in each i-th spectral band. The intensity value for each position in each i-th spectral band is adjusted to generate an adjusted intensity value for each position in each i-th spectral band in accordance with ##EQU1## where S is the number of unique spectral bands included in said digital data, W.sub.n is a weighting factor and * denotes the convolution operator. Each surround function F.sub.n (x,y) is uniquely scaled to improve an aspect of the digital image, e.g., dynamic range compression, color constancy, and lightness rendition. The adjusted intensity value for each position in each i-th spectral band is filtered with a common function and then presented to a display device. For color images, a novel color restoration step is added to give the image true-to-life color that closely matches human observation.

  10. Resolution in digital imaging: enough already?

    PubMed

    Siegel, Daniel Mark

    2002-09-01

    Digital images have become the new currency for the exchange of information in dermatology. The main value of the digital image, its ability to be transported via the Internet, is optimal if the image can be shared by all interested parties without the need for the still relatively uncommon broadband connection. The technology behind these captured images is progressing rapidly with a resultant increase in image size and resolution. For all practical purposes in clinical dermatology, the current technology with regard to resolution has already gone beyond the needs of the clinician. This article, using freeware and commercially used software, offers proof that a single megapixel image is adequate for on screen evaluation and publication purposes.

  11. Image Processing Occupancy Sensor

    SciTech Connect

    2016-07-14

    The Image Processing Occupancy Sensor, or IPOS, is a novel sensor technology developed at the National Renewable Energy Laboratory (NREL). The sensor is based on low-cost embedded microprocessors widely used by the smartphone industry and leverages mature open-source computer vision software libraries. Compared to traditional passive infrared and ultrasonic-based motion sensors currently used for occupancy detection, IPOS has shown the potential for improved accuracy and a richer set of feedback signals for occupant-optimized lighting, daylighting, temperature setback, ventilation control, and other occupancy and location-based uses. Unlike traditional passive infrared (PIR) or ultrasonic occupancy sensors, which infer occupancy based only on motion, IPOS uses digital image-based analysis to detect and classify various aspects of occupancy, including the presence of occupants regardless of motion, their number, location, and activity levels of occupants, as well as the illuminance properties of the monitored space. The IPOS software leverages the recent availability of low-cost embedded computing platforms, computer vision software libraries, and camera elements.

  12. The FBI compression standard for digitized fingerprint images

    SciTech Connect

    Brislawn, C.M.; Bradley, J.N.; Onyshczak, R.J.; Hopper, T.

    1996-10-01

    The FBI has formulated national standards for digitization and compression of gray-scale fingerprint images. The compression algorithm for the digitized images is based on adaptive uniform scalar quantization of a discrete wavelet transform subband decomposition, a technique referred to as the wavelet/scalar quantization method. The algorithm produces archival-quality images at compression ratios of around 15 to 1 and will allow the current database of paper fingerprint cards to be replaced by digital imagery. A compliance testing program is also being implemented to ensure high standards of image quality and interchangeability of data between different implementations. We will review the current status of the FBI standard, including the compliance testing process and the details of the first-generation encoder.

  13. BPSK Demodulation Using Digital Signal Processing

    NASA Technical Reports Server (NTRS)

    Garcia, Thomas R.

    1996-01-01

    A digital communications signal is a sinusoidal waveform that is modified by a binary (digital) information signal. The sinusoidal waveform is called the carrier. The carrier may be modified in amplitude, frequency, phase, or a combination of these. In this project a binary phase shift keyed (BPSK) signal is the communication signal. In a BPSK signal the phase of the carrier is set to one of two states, 180 degrees apart, by a binary (i.e., 1 or 0) information signal. A digital signal is a sampled version of a "real world" time continuous signal. The digital signal is generated by sampling the continuous signal at discrete points in time. The rate at which the signal is sampled is called the sampling rate (f(s)). The device that performs this operation is called an analog-to-digital (A/D) converter or a digitizer. The digital signal is composed of the sequence of individual values of the sampled BPSK signal. Digital signal processing (DSP) is the modification of the digital signal by mathematical operations. A device that performs this processing is called a digital signal processor. After processing, the digital signal may then be converted back to an analog signal using a digital-to-analog (D/A) converter. The goal of this project is to develop a system that will recover the digital information from a BPSK signal using DSP techniques. The project is broken down into the following steps: (1) Development of the algorithms required to demodulate the BPSK signal; (2) Simulation of the system; and (3) Implementation a BPSK receiver using digital signal processing hardware.

  14. Beam quality measurements using digitized laser beam images

    SciTech Connect

    Duncan, M.D. ); Mahon, R. )

    1989-11-01

    A method is described for measuring various laser beam characteristics with modest experimental complexity by digital processing of the near and far field images. Gaussian spot sizes, peak intensities, and spatial distributions of the images are easily found. Far field beam focusability is determined by computationally applying apertures of circular of elliptical diameters to the digitized image. Visualization of the magnitude of phase and intensity distortions is accomplished by comparing the 2-D fast Fourier transform of both smoothed and unsmoothed near field data to the actual far field data. The digital processing may be performed on current personal computers to give the experimenter unprecedented capabilities for rapid beam characteriztion at relatively low cost.

  15. Blood flow determination using recursive processing: a digital radiographic method

    SciTech Connect

    Kruger, R.A.; Bateman, W.; Liu, P.Y.; Nelson, J.A.

    1983-10-01

    Temporal filtration of fluoroscopic video sequences is being used as an alternative to pulsed digital subtraction angiography. Using the same image processing architecture and a slight modification in processing logic a parametric image can be synthesized from such a temporally filtered image sequence in virtual real time, i.e., an image sequence that spans T seconds takes exactly T seconds to process. Off-line computer processing is not required. Initial phantom studies imply that the time to maximum opacification (t/sub max/) can be used to determine absolute and relative blood flow with a high confidence level (r > .989). Phantom and animal examples are presented.

  16. Digital retrospective motion-mode display and processing of electron beam cine-computed tomography and other cross-sectional cardiac imaging techniques

    NASA Astrophysics Data System (ADS)

    Reed, Judd E.; Rumberger, John A.; Buithieu, Jean; Behrenbeck, Thomas; Breen, Jerome F.; Sheedy, Patrick F., II

    1995-05-01

    displays give the operator valuable feedback pertaining to the contiguity of the extracted surfaces. As with M-Mode echocardiography, the velocity of moving structures can be easily visualized and measured. However, many views inaccessible to standard transthoracic echocardiography are easily generated. These features have augmented the interpretability of cine electron beam computed tomography and have prompted the recent cloning of this system into an 'omni-directional M-Mode display' system for use in digital post-processing of echocardiographic parasternal short axis tomograms. This enhances the functional assessment in orthogonal views of the left ventricle, accounting for shape changes particularly in the asymmetric post-infarction ventricle. Conclusions: A new tool has been developed for analysis and visualization of cine electron beam computed tomography. It has been found to be very useful in verifying the consistency of myocardial surface definition with a semi-automated segmentation tool. By drawing on M-Mode echocardiography experience, electron beam tomography's interpretability has been enhanced. Use of this feature, in conjunction with the existing image processing tools, will enhance the presentations of data on regional systolic and diastolic functions to clinicians in a format that is familiar to most cardiologists. Additionally, this tool reinforces the advantages of electron beam tomography as a single imaging modality for the assessment of left and right ventricular size, shape, and regional functions.

  17. Advanced Digital Signal Processing for Hybrid Lidar

    DTIC Science & Technology

    2013-09-30

    Advanced Digital Signal Processing for Hybrid Lidar William D. Jemison Clarkson University [Technical Section Technical Objectives The technical...objective of this project is the development and evaluation of various digital signal processing (DSP) algorithms that will enhance hybrid lidar ...algorithm as shown in Figure 1. Hardware Platform for Algorithm Implementation + Underwater Channel Characteristics ^ Lidar DSP Algorithm Figure

  18. Digital image compression for a 2f multiplexing optical setup

    NASA Astrophysics Data System (ADS)

    Vargas, J.; Amaya, D.; Rueda, E.

    2016-07-01

    In this work a virtual 2f multiplexing system was implemented in combination with digital image compression techniques and redundant information elimination. Depending on the image type to be multiplexed, a memory-usage saving of as much as 99% was obtained. The feasibility of the system was tested using three types of images, binary characters, QR codes, and grey level images. A multiplexing step was implemented digitally, while a demultiplexing step was implemented in a virtual 2f optical setup following real experimental parameters. To avoid cross-talk noise, each image was codified with a specially designed phase diffraction carrier that would allow the separation and relocation of the multiplexed images on the observation plane by simple light propagation. A description of the system is presented together with simulations that corroborate the method. The present work may allow future experimental implementations that will make use of all the parallel processing capabilities of optical systems.

  19. Real photographic prints from digital images.

    PubMed

    Ratner, D

    2000-08-01

    Digital photography is emerging as a standard method of documenting preoperative, intraoperative, and postoperative results in the clinical setting. While hard copies of these electronic images can be quickly and easily generated on color laser or inkjet printers, there are times when it is necessary to generate a true photographic print of an image, either for insurance documentation or to meet the publication requirements of a peer-reviewed journal. Standard inkjet and laser printers are unable to generate true photographic prints. To identify a rapid, cost-effective means of generating high-quality photographs of digital images. We describe the use of on-line service bureaus with digital photographic printers to obtain high-quality photographic prints of patient images. From as little as 49 cents per print, a color or black-and-white print of a color image can be generated by an on-line service bureau to satisfy the need for a photographic quality hard copy. While color laser or inkjet printers allow physicians to generate their own hard copies of electronic patient images, photographic quality images are at times needed to satisfy requirements for insurance documentation or publication in peer-reviewed journals. Use of on-line service bureaus is the most cost-effective way that we have found to obtain high-quality photographic color or black-and-white prints from electronically stored patient images.

  20. Characterization of the Campbell-Stokes sunshine duration recorder and its ability to derive direct solar radiation by using digital image processing

    NASA Astrophysics Data System (ADS)

    Sanchez-Romero, Alejandro; González, Josep-Abel; Calbó, Josep; Sanchez-Lorenzo, Arturo

    2014-05-01

    The World Meteorological Organization defines the sunshine duration (SD) as the time that, along a given period, direct solar irradiance (DSI) exceeds the threshold level of 120 W/m2. Since the end of 19th century, the Campbell-Stokes sunshine recorder (CSSR) has been the most commonly used instrument used for measuring SD. Due to the large number of long records that exist worldwide, valuable climatic information can be extracted from them. Many authors have used the daily SD (as obtained from the measurement of the length of burn for a given card) to obtain additional information about solar radiation, by using Ångström-Prescott type formulas. Contrarily, the burn width has not been systematically used. Theoretically, the burn is wider (narrower) when the direct insolation is stronger (weaker). The aim of this research is to show the relationship between burn width and DSI, and to prove whether this relationship depends on the type of CSSR and burning card. The research has been carried out in Girona (NE Spain) for a period of two years (from January 2012 to January 2014). Two different models of CSSR (which use different types of cards) and a pyrheliometer from Kipp&Zonen were used to measure SD and DSI, respectively. A semi-automatic method based on image processing of digital scanned images of burnt cards is presented. The method can be summarized in four steps: (i) scan each band on a green background; (ii) apply a digital process to increase the contrast of the burn; (iii) define two/three points in the image, depending of the geometry of the card, to point the center of the day (12.00 TST) on the image and define the trajectory of the sun with 1-minute intervals; and (iv) apply a program to make cross-sections every minute and measure the width of burn. So, after all of this process, we obtain a temporal evolution of the burn width with 1-minute resolution and distinguishing between morning and afternoon. The results show that there is a good correlation