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Conference on MOEMS and Miniaturized Systems IV

作者： Levitan, SP Kurzweg, TP Martinez, JA Kahrs, M Bakos, J Windish, C Boles, J Hansson, J Wiesser, M Kuznia, C Chiarulli, DM Univ Pittsburgh Dept EE Pittsburgh PA 15261 USA

ISBN: (纸本)0819452548

Densely integrated systems in the future will incorporate device and communication technologies that span the domains of digital and analog electronics, optics, micro-mechanics, and micro-fluidics. Given the fundamental differences in substrate materials, feature scale and processing requirements between integrated devices in these domains, it is likely that multi-chip, system-in-package, integration solutions will be required for the foreseeable future. The multi-domain nature of these systems necessitates design tools that span multiple energy domains, time and length scales, a's well as abstraction levels. This. paper describes a case study of the modeling of a photonic/multi-technology system based on a 3D volumetric packaging technology implemented with Fiber image Guide (FIG), based technology. It is 64x64 fiber crossbar switch implementation using three Silicon-on-Sapphire mixed signal switch die with flip-chip bonded VCSEL and detector arrays. We show a single end-to-end system simulation. of. the O/E crossbar working across the domains of free-space and guided wave optical propagation, GaAs O/E and E/O devices, analog drivers and receivers and integrated digital control.

关键词： Switches Analog electronics Vertical cavity surface emitting lasers Systems modeling Digital electronics Microopto electromechanical systems signal detection Chemical elements Device simulation Waveguides

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Simple method for multiplexing channels in a Fourier Optical Processor

Simple method for multiplexing channels in a Fourier Optical...

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5th Iberoamerican Meeting on Optics/8th Latin American Meeting on Optics, Lasers, and Their applications

作者： Palma, S Barbé, J Campos, J Iemmi, C Univ Autonoma Barcelona Dept Fis Bellaterra 08193 Spain

ISBN: (纸本)081945575X

Ones of the most popular devices used into optical processors to display the images are the liquid crystal spatial light modulators (LCSLMs). Manny applications in signal procession tasks use images with less resolution than the modem LCSLMs can be support. In this contribution we propose a new method based in a spatial multiplexing that uses the high resolution of the modem LCSLMs to introduce several channels in an optical correlator. The proposed method for the channels codification is based onto multirresolution analysis. Given an RGB image, before it will be displayed in LCSLM screen, a computer decompose the image in R,G and B channels and for each channel calculates a set of 50%, 25% and 12.5% scaled replicas. Then, in the place of the image, the computer send to LCSLM screen a composite scene with the original image and its replicas. Each of the images displayed in the scene defines one different channel in the optical correlator. In order to prove the method we develop an application based on signal analysis using a bank of 16 Gabor filters, that decompose the signal. in 16 frequency channels (four orientations 0degrees, 45degrees, 90degrees, 135degrees and four frequencies (1)/(4), 1/8, 1/16, 1/32 cycles/pixels). With the proposed channels codification, a complete set of 16 filtered R, G and B images can be obtained using only 4 cycles of the optical processors, that minds that we increased the speed of the processor by factor 4.

关键词： optical processors image processing Fourier optics

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Digital photography: A primer for pathologists

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JOURNAL OF CLINICAL LABORATORY ANALYSIS 2004年第2期18卷 91-128页

作者： Riley, RS Ben-Ezra, JM Massey, D Slyter, RL Romagnoli, G Virginia Commonwealth Univ Dept Pathol Richmond VA 23298 USA

The computer and the digital camera provide a unique means for improving hematology education, research, and patient service. High quality photographic images of gross specimens can be rapidly and conveniently acquired with a high-resolution digital camera, and specialized digital cameras have been developed for photomicroscopy. Digital cameras utilize charge-coupled devices (CCD) or Complementary Metal Oxide Semiconductor (CMOS) image sensors to measure light energy and additional circuitry to convert the measured information into a digital signal. Since digital cameras do not utilize photographic film, images are immediately available for incorporation into web sites or digital publications, printing, transfer to other individuals by email, or other applications. Several excellent digital still cameras are now available for less than $2,500 that capture high quality images comprised of more than 6 megapixels. These images are essentially indistinguishable from conventional film images when viewed on a quality color monitor or printed on a quality color or black and white printer at sizes up to 11 x 14 inches. Several recent dedicated digital photomicroscopy cameras provide an ultrahigh quality image output of more than 12 megapixels and have low noise circuit designs permitting the direct capture of darkfield and fluorescence images. There are many applications of digital images of pathologic specimens. Since pathology is a visual science, the inclusion of quality digital images into lectures, teaching handouts, and electronic documents is essential. A few institutions have gone beyond the basic application of digital images to developing large electronic hematology atlases, animated, audio-enhanced learning experiences, multidisciplinary Internet conferences, and other innovative applications. Digital images of single microscopic fields (single frame images) are the most widely utilized in hematology education at this time, but single images of many adjacent micr

关键词： photography photomicrography microscopy microcomputers telepathology optics image processing medical illustration

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The implementation of thermal image visualization by HDL based on pseudo-color

The implementation of thermal image visualization by HDL bas...

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Conference on applications of Digital image processing xxVII

作者： Zhu, Y Zhang, JL Wuhan Inst Sci & Technol Wuhan 430073 Peoples R China

ISBN: (纸本)0819454966

The pseudo-color method which maps the sampled data to intuitive perception colors is a kind of powerful visualization way: And the all-around system of pseudo-color visualization, which includes the primary principle, model and HDL (Hardware Description Language) implementation for the thermal images, is expatiated on in the paper. The thermal images whose signal is modulated as video reflect the temperature distribution of measured object, so they have the speciality of mass and real-time. The solution to the intractable problem is as follows: First, the reasonable system, i.e. the combining of global pseudo-color visualization and local special area accurate measure, muse be adopted. Then, the HDL pseudo-color algorithms in SoC (System on Chip) carry out the system to ensure the real-time. Finally, the key HDL algorithms for direct gray levels connection coding, proportional gray levels map coding and enhanced gray levels map coding are presented, and its simulation results are showed. The pseudo-color visualization of thermal images implemented by HDL in the paper has effective application in the aspect of electric power equipment test and medical health diagnosis.

关键词： pseudo-color visualization HDL (Hardware Description Language) thermal image

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Streaming video and rate scalable compression: what are the challenges for watermarking?

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JOURNAL OF ELECTRONIC IMAGING 2004年第1期13卷 198-208页

作者： Lin, ET Podilchuk, CI Kalker, T Delp, EJ Purdue Univ Sch Elect & Comp Engn Video & Image Proc Lab W Lafayette IN 47906 USA Bell Labs Lucent Technol Murray Hill NJ 07974 USA Philips Res Labs Eindhoven Netherlands

Video streaming, or the real-time delivery of video over a data network, is the underlying technology behind many applications including video conferencing, video on demand, and the delivery of educational and entertainment content In many applications, particularly ones involving entertainment content, security issues, such as conditional access and copy protection, must be addressed. To resolve these security issues, techniques that include encryption and watermarking need to be developed. Since video sequences will often be compressed using a scalable compression technique and transported over a lossy packet network using the Internet Protocol (IP), security techniques must be compatible with the compression method and data transport and be robust to errors. We address the issues involved in the watermarking of rate-scalable video streams delivered using a practical network. Watermarking is the embedding of a signal (the watermark) into a video stream that is imperceptible when the stream is viewed, but can be detected by a watermark detector. Many watermarking techniques have been proposed for digital images and video, but the issues of streaming have not been fully investigated. A review of streaming video is presented, including scalable video compression and network transport, followed by a brief review of video watermarking and the discussion of watermarking streaming video. (C) 2004 SPIE and IST.

关键词： Video Digital watermarking Video compression Receivers Video surveillance Error analysis Internet Network security Video processing Sensors

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Spatial selectivity modulated just-noticeable-distortion profile for video

Spatial selectivity modulated just-noticeable-distortion pro...

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Proceedings - IEEE International Conference on Acoustics, Speech, and signal processing

作者： Lu, Zhongkang Lin, Weist Yang, x.K. Ong, E.P. Yao, S.S. Institute for Infocomm. Research Agy. for Sci. Technol. and Research 21 Heng Mui Keng Terrace Singapore 119613

Both visual sensitivity and spatial selectivity determine the overall visibility threshold at each pixel in an image, according to the physiological and psychological evidence towards the human vision system (HVS). Visual sensitivity can be decided by an existing estimator for Just-Noticeable- Distortion (JND). In this paper, a computational model is proposed for incorporating a selectivity measure into the JND profile so that more effective noise shaping is possible in various applications. Experimental results with noise-embedded video sequences confirm that introduction of spatial selectivity enhances the performance of JND profile used in noise shaping.

关键词： Video signal processing

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Monolithic active pixel sensors with in-pixel double sampling operation and column-level discrimination

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IEEE TRANSACTIONS ON NUCLEAR SCIENCE 2004年第5期51卷 2313-2321页

作者： Deptuch, G Claus, G Colledani, C Degerli, Y Dulinski, W Fourches, N Gaycken, G Grandjean, D Himmi, A Hu-Guo, C Lutz, P Rouger, M Valin, I Winter, M LEPSI F-67037 Strasbourg 02 France CEA Saclay SEDI DAPNIA F-91191 Gif Sur Yvette France SPP F-91191 Gif Sur Yvette France ULP CNRS IReS IN2P3 F-67037 Strasbourg 02 France

Monolithic active pixel sensors constitute a viable alternative to hybrid pixel sensors and charge coupled devices for the next generation of vertex detectors. Possible applications will strongly depend on a successful implementation of on-chip hit recognition and sparsification schemes. The task is tough, first because of very small signal amplitudes (similar to mV), which are of the same order of magnitude as natural dispersions in the transistor threshold voltages, secondly because of the limitation to use only one type of transistor over the sensitive area. This paper presents a 30 x 128 pixel prototype chip, featuring fast, column parallel signal processing. The pixel concept combines in-pixel amplification with double sampling operation. The pixel output is a differential current signal proportional to the difference between the reference level and the charge collected. The readout of the pixel is two-phase, matching discrimination circuitry implemented at the end of each column. Low-noise discriminators feature autozero functionality. The details of the chip design are presented. Difficulties, encountered in the first attempt to address on-line hit recognition, are reported. Performances of the pixel and discriminator blocks, determined in separate measurements, are discussed. An important part of this paper consists of results of first tests performed with soft x-rays from a Fe-55 source.

关键词： APS CMOS APS double sampling image sensors particle detector pixel detectors system-on-chip

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Design of a high definition imaging (HDI) analysis technique adapted to challenging environments

Design of a high definition imaging (HDI) analysis technique...

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Conference on applications of Digital image processing xxVII

作者： Laurent, S Karl, WC Konrad, J Wilson, J Baumgardner, J Mendillo, M Boston Univ Dept Elect & Comp Engn Boston MA 02215 USA

ISBN: (纸本)0819454966

This paper presents a highly automated, more accurate approach to High Definition Imaging (HDI) using low signal-to-noise digital videos recorded at ground-based telescopes. The HDI approach involves the acquisition of a video sequence (10(3) - 10(5) fields) taken through a turbulent atmosphere followed by three-step post-processing. The specific goal is to be able to reproduce expert results, while limiting human interaction, to study both surface features and the atmospheres of planets and moons. The telescopes used here are preferably small and not equipped with Adaptive Optics. The three steps include registration, selection and restoration. First, registration, based on a template, is performed to find the exact position of each object. Then only higher-quality frames are selected by a criterion based on a measure of the blur in a region of interest around that object. The best quality frames are then shifted and added together to create an effective time exposure under ideal observing conditions. The last step is to remove distortions in the image, caused by the atmosphere and the optical equipment, through a regularized deconvolution of instrument and residual atmospheric blur. This procedure is done first in the white light domain, and then the registration information obtained there is applied to spectral data.

关键词： image registration selection criterion restoration 1(1) regularization atmospheric blur turbulence ground-based telescope white light spectral

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A new lifting scheme for lossless image compression

A new lifting scheme for lossless image compression

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Conference on applications of Digital image processing xxVII

作者： Hou, HS Aerosp Corp Los Angeles CA 90009 USA

ISBN: (纸本)0819454966

Since its first introduction, the lifting scheme(1,2) has become a powerful method to perform wavelet transforms and many other orthogonal transforms. Especially for integer-to-integer wavelet transforms, the lifting scheme is an indispensable tool for lossless image compression. Earlier work has shown that the number of lifting steps can have an impact on the transform performance.(3) The fidelity of integer-to-integer transforms depends entirely on how well they approximate their original wavelet transforms. The predominant source of errors is due to the rounding-off of the intermediate real result to an integer at each lifting step. Hence, a wavelet transform with a large number of lifting steps would automatically increase the approximation error. In the case of lossy compression, the approximation error is less important because it is usually masked out by the transform coefficient quantization error. However, in the case of lossless compression, the compression performance is certainly affected by the approximation error. Consequently, the number of lifting steps in a wavelet transform is a major concern. The new lifting method presented in this paper reduces the number of lifting steps substantially in lossless data compression. Thus, it also significantly improves the overall rounding errors incurred in the real-to-integer conversion process at each of the lifting steps. The improvement of the overall rounding errors is more pronounced in the integer-to-integer orthogonal wavelet transforms, but the improvement in the integer-to-integer biorthogonal wavelet transforms is also significant. In addition, as a dividend, the new lifting method further saves memory space and decreases signal delay. Many examples on popular wavelet transforms are included.

关键词： integer-to-integer transform image compression lifting method lossless image compression wavelet transform

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Determination of the optimal electrical bandwidth in CCD- and CMOS-based image detector applications

Determination of the optimal electrical bandwidth in CCD- an...

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Conference on Optical and Infrared Detectors for Astronomy

作者： Philbrick, RH Ball Aerosp & Technol Corp Boulder CO 80306 USA

ISBN: (纸本)0819454311

Limiting the electrical frequency response of the output video prior to analog-to-digital conversion is a common technique used to maximize the signal to noise ratio in imaging systems employing CCD and CMOS based solid-state detectors. Bandwidth limiting effectively reduces the magnitude of the stochastic noise in the video signal prior to digitization;but this filtering action can also change the information content in the video stream if it is applied too liberally. Various "rules of thumb" exist in the detector community for setting the bandwidth in video processing electronics. However, it will be. shown that significant signal errors can be induced in many applications if such general design practices are followed implicitly. This paper addresses the general question of how to optimize bandwidth limiting in systems employing either CCD or CMOS based detectors. Induced errors in pixel signal and spatial frequency response (MTF) are analyzed as a function of bandwidth limiting for both CCD and CMOS based detectors and recommended bandwidth values are presented for systems utilizing 8 through 18 bit analog-to-digital converters.

关键词： CCD CMOS bandwidth jitter noise MTF

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