this paper presents a short historical perspective of color reproduction technology, where we are at present, and what challenges lie ahead. today prevalent color managementsystems are based on pixel-wise processing ...
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Quantification of vessel diameters of artherosclerotic or congenital stenosis is very important for the diagnosis of vascular diseases. the aorta extraction and cross-section calculation is a software-based applicatio...
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ISBN:
(纸本)0819457183
Quantification of vessel diameters of artherosclerotic or congenital stenosis is very important for the diagnosis of vascular diseases. the aorta extraction and cross-section calculation is a software-based application that offers a three-dimensional, platform-independent, colorized visualization of the extracted aorta with augmented reality information of MRt or Ct datasets. this project is based on differenttypes of specialized imageprocessingalgorithms, dynamical particle filtering and complex mathematical equations. From this three-dimensional model a calculation of minimal cross sections is performed. In user specified distances, the aorta is cut in differently defined directions which are created through vectors with varying length. the extracted aorta and the derived minimal cross-sections are then rendered with the marching cube algorithm and represented together in a three-dimensional virtual reality with a very high degree of immersion. the aim of this study was to develop an imaging software that delivers cardiologists the possibility of (i) furnishing fast vascular diagnosis, (ii) getting precise diameter information, (iii) being able to process exact, local stenosis detection (iv) having permanent data storing and easy access to former datasets, and (v) reliable documentation of results in form of tables and graphical printouts.
this paper proposes an adaptive error diffusion algorithm for text enhancement followed by an efficienttext segmentation that uses the maximum gradient difference (MGD). the gradients are calculated along with scan l...
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Remotely sensed satellite imagery of an earthquake-affected area can significantly assist in estimating the severity of infrastructure damage. Modern high-resolution satellite systems have been launched to provide use...
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Semifragile watermarking techniques aim to preventtampering and fraudulent use of modified images. A semifragile watermark monitors the integrity of the content of the image but not its numerical representation. ther...
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Semifragile watermarking techniques aim to preventtampering and fraudulent use of modified images. A semifragile watermark monitors the integrity of the content of the image but not its numerical representation. therefore, the watermark is designed so thatthe integrity is proven if the content of the image has not been tampered with, despite some mild processing on the image. However, if parts of the image are replaced with the wrong key or are heavily processed, the watermark information should indicate evidence of forgery. We compare the performance of eight semifragile watermarking algorithms in terms of their miss probability under forgery attack, and in terms of false alarm probability under nonmalicious signal processing operations that preserve the content and quality of the image. We propose desiderata for semifragile watermarking algorithms and indicate the promising algorithms among existing ones. (C) 2004 spie and ISt.
the inspection and monitoring of the wear of grinding tools is essential to ensure the quality of the grinding tool surface and the finished product Most of the current methods for examining a grinding tool surface re...
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the inspection and monitoring of the wear of grinding tools is essential to ensure the quality of the grinding tool surface and the finished product Most of the current methods for examining a grinding tool surface rely on dismounting the grinding tool. Often, the state of the grinding tool surface is checked indirectly by evaluating the quality of the workpiece. We describe the application of imageprocessing, which offers an effective means for in situ inspection and monitoring. It yields more detailed information aboutthe surface and the kind of wear observed than the common methods. By using multidirectional illumination and image fusion, an image with a high degree of relevant information is generated that is then segmented using the wavelettransform (multiscale analysis) and classified to distinguish grains and cavities on the surface. Results of the application of the algorithms for a high-performance grinding tool with CBN grains embedded in a resin base are presented. (C) 2004 spie and ISt.
the inspection and monitoring of the wear of grinding tools is essential to ensure the quality of the grinding tool surface and the finished product Most of the current methods for examining a grinding tool surface re...
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ISBN:
(纸本)0819449989
the inspection and monitoring of the wear of grinding tools is essential to ensure the quality of the grinding tool surface and the finished product Most of the current methods for examining a grinding tool surface rely on dismounting the grinding tool. Often, the state of the grinding tool surface is checked indirectly by evaluating the quality of the workpiece. We describe the application of imageprocessing, which offers an effective means for in situ inspection and monitoring. It yields more detailed information aboutthe surface and the kind of wear observed than the common methods. By using multidirectional illumination and image fusion, an image with a high degree of relevant information is generated that is then segmented using the wavelettransform (multiscale analysis) and classified to distinguish grains and cavities on the surface. Results of the application of the algorithms for a high-performance grinding tool with CBN grains embedded in a resin base are presented. (C) 2004 spie and ISt.
the approximation in the maximally distinct or under sampled filter banks is considered. In this discussion, the decimated sampling interval t satisfies t greater than or equal to M, where M is the number of paths of ...
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ISBN:
(纸本)0819448141
the approximation in the maximally distinct or under sampled filter banks is considered. In this discussion, the decimated sampling interval t satisfies t greater than or equal to M, where M is the number of paths of the filter banks. Moreover, we presentthe optimum transmultiplexer tR. this result is extended to the design of wireless transmultiplexer, used in CDMA systems, for example.
Future earth observation optical systems will be more and more demanding in terms of ground sampling distance, swath width, number of spectral bands, duty cycle. Existing architectures of focal planes and video proces...
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ISBN:
(纸本)0819448176
Future earth observation optical systems will be more and more demanding in terms of ground sampling distance, swath width, number of spectral bands, duty cycle. Existing architectures of focal planes and video processingelectronics are hardly compatible with these new requirements: electronic functions are splitted in several units, and video processing is limited to frequencies around 5 MHz in order to fulfil the radiometric requirements expected for high performance image quality systems. this frequency limitation induces a high number of video chains operated in parallel to process the huge amount of pixels at focal plane output, and leads to unacceptable mass and power consumption budgets. Furthermore, splitting the detection electronics functions into several units (at least one for the focal plane and proximity electronics, and one for the video processing functions) does not optimize the production costs specific development efforts must be performed on critical analog electronics at each equipment level and operations of assembly, integration and tests are duplicated at equipment and subsystem levels. taking into accountthese constraints, Alcatel Space has developed with CNES a new concept of Highly Integrated Detection electronic Subsystem (SEDHI). this paper presents the design of this new concept and summarizes the main performances which have been measured at component and subsystem levels. the electrical, mechanical and thermal aspects of the SEDHI concept are described, including the basic technologies : ASIC for phase shift of detector clocks, ASIC for video processing, ASIC for phase trimming, hybrids, multi chip modules... the adaptability to a large amount of missions and optical instruments is also discussed. Design, performance and budgets of the subsystem are given for the Pleiades mission (successor of SPOt) for which the SEDHI concept has been selected.
We have developed a new concept, high-speed and high-resolution color scanner (Blinkscan) using digital camera technology. With our most advanced sub-pixel imageprocessingtechnology, approximately 12 million pixel i...
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ISBN:
(纸本)0819448176
We have developed a new concept, high-speed and high-resolution color scanner (Blinkscan) using digital camera technology. With our most advanced sub-pixel imageprocessingtechnology, approximately 12 million pixel image data can be captured. High resolution imaging capability allows various uses such as OCR, color document read, and document camera. the scan time is only about 1 seconds for a letter size sheet. Blinkscan scans documents placed "face up" on its scan stage and without any special illumination lights. Using Blinkscan, a high-resolution color document can be easily inputted into a PC at high speed, a paperless system can be built easily. It is small, and since the occupancy area is also small, setting it on an individual desk is possible. Blinkscan offers the usability of a digital camera and accuracy of a flatbed scanner with high-speed processing. Now, about several hundred of Blinkscan are mainly shipping for the receptionist operation in a bank and a security. We will show the high-speed and high-resolution architecture of Blinkscan. Comparing operation-time with conventional image capture device, the advantage of Blinkscan will make clear. And image evaluation for variety of environment, such as geometric distortions or non-uniformity of brightness, will be made.
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