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Conference on digital compression technologies and Systems for video Communications

作者： Lee, CB Hong, SH Park, RH ETRI NEW MEDIA SERV SECTTAEJON 305600SOUTH KOREA

ISBN: (纸本)0819423564

In transmission of image sequences over ATM networks, the channel sharing efficiency in packet loss conditions is important. As one of possible approaches two-layer video coding methods have been proposed. These methods transmit video information over the network with different levels of protection with respect to packet loss. In this paper, a two-layer coding method using pyramid structure is proposed and several realizations of two-layer video coding methods are presented and their performances are compared.

关键词： Image quality video coding Image transmission Image compression video Asynchronous transfer mode Image resolution Image processing Quantization Multiplexing

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Structure-based fractal image coding

Structure-based fractal image coding

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Conference on digital compression technologies and Systems for video Communications

作者： Titkov, B Tikhotskij, A Myboroda, A Buley, H TELEVIS RES INST NIITST PETERSBURGRUSSIA

ISBN: (纸本)0819423564

An image coding scheme using partitioned iterated function systems (fractal codec) is presented. It extends the usual block-based algorithms with quadtree partitioning by splitting with arbitrarily shaped masks. Besides the general advantages of fractal coding such as very high compression and scalable decoding this gives provision for shape- adaptive coding. Furthermore the usage of orthogonal luminance transformations results in code suitable for browsing. The codec now uses up to 256 masks at each level of the quadtree partition (up to four levels) which may be applied twice. The mask set was experimentally optimized on a set of images. The high degree of flexibility is handled besides the usage of the known 'multidimensional nearest neighbor search' by an estimation of useful masks based on a block-structure analysis. Fractal referencing to parts of the image already coded allows for additional reduction of data rate. Controlling takes into account the compression efficiency of the different types of approximation. The bit stream of the encoded image is structured, pre-encoded and selectivity entropy coded by arithmetic coding. Remaining blocking artifacts are concealed by a generally applicable method called bending, which is designed to avoid blurring by filtering.

关键词： image compression fractal coding block-boundary-artefact concealment

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SCALABLE IMAGE compression USING COMBINED WAVELET TRANSFORM AND VECTOR QUANTIZATION

SCALABLE IMAGE COMPRESSION USING COMBINED WAVELET TRANSFORM ...

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Conference on digital video compression - algorithms and technologies 1995

作者： PANCHANATHAN, S JAIN, A GAMAZ, N UNIV OTTAWA DEPT ELECT ENGNMULTIMEDIA COMMUN RES LABOTTAWAON K1N 6N5CANADA

ISBN: (纸本)0819417661

In this paper, we propose vector quantization (VQ) based scheme for scalable image compression. Scalability is a generic feature referring to image representation in different sizes (spatial scalability) and/or picture qualities (SNR scalability). VQ is a powerful technique for low bit rate image compression. However the conventional VQ approach does not provide a scalable bitstream. We propose a VQ based algorithm (SVQ) to achieve spatial scalability. In SVQ technique, a pyramidal structure of three layers is built by applying 2D wavelet downsampling filters on the input image. The label stream is then made scalable such that a smaller-size image can be obtained by decoding a portion of the bitstream. This image can be further enhanced in size by progressively decoding the remaining bits. This algorithm ensures partial decodability of VQ labels by using separate codebooks one for each spatial resolution. We then propose a combination of wavelet transform and SVQ technique called WSVQ to exploit the cross-correlations among wavelet sub-bands. Simulation results confirm the substantial reductions in bit rate and superior subjective image quality at each spatial resolution using the proposed algorithm, at a significantly reduced computational complexity.

关键词： Image compression Wavelets Wavelet transforms Spatial resolution Quantization Image quality Image resolution Signal to noise ratio Image enhancement Image filtering

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The Equator MAP-CA™ DSP:: An end-to-end broadband signal Processor™ VLIW

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IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR video TECHNOLOGY 2002年第8期12卷 646-659页

作者： Basoglu, C Lee, W O'Donnell, J Equator Technol Inc Seattle WA 98101 USA

Today's multimedia services, both at the server/head end and the client/consumer end, require high computational performance to support video encoding, decoding, and transcoding. Traditionally, the processing requirements have been met by application-specific processors (ASICs). What once were standalone single-function devices are now network-connected, multifunction service platforms-the Internet-ready digital television/video recorder/teleconference/game platform, for example. As a result, these platforms now must support multiple image formats, compression standards, and processing algorithms. Equator technologies has developed a high-performance, programmable system on a chip, the MAP-CA digital signal processor (DSP), to address this requirement. The MAP-CA DSP combines general-purpose reduced instruction set computer processing with high-performance image and signal processing in a very long instruction word framework. The chip is designed to replace hardwired ASICs in a variety of products, including digital head-end, networking products, and consumer applications. We present an analysis of the MAP-CA DSP architecture and provide several performance benchmarks with popular media processing applications.

关键词： DSP image multimedia processor optimizing compiler real-time media processing and implementation video and audio algorithms

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Vertex tracking for grid-based motion compensation

Vertex tracking for grid-based motion compensation

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Conference on digital compression technologies and Systems for video Communications

作者： Schroder, K UNIV DORTMUND LEHRSTUHL NACHRICHTENTECHD-44221 DORTMUNDGERMANY

ISBN: (纸本)0819423564

To overcome some of the well-known artefacts stemming from block-based motion compensation, grid-based techniques have been proposed in the past as a promising alternative to block matching. While the latter is restricted to simple translational motion, grid-based compensation employs e.g. an affine model when triangular meshes are assumed. The theoretically superior model, however, will perform worse at object boundaries where the connectivity constraint of the meshes causes smoothing of the underlying discontinuous motion vector field. This effect can be diminished by providing an individual grid for each object in a scene. The crucial part of grid-based motion prediction is the technique of tracking mesh vertices. In contrast to block matching, motion estimation of vertices cannot be done independently without sacrificing prediction gain. This paper discuses different algorithms for vertex tracking. The issue of tracking at object boundaries and the influence of the resampling algorithm on the prediction gain are addressed in detail. Object grids, carrying both shape and motion information, are evaluated further in terms of shape coding efficiency and temporal scalability. Both aspects become important when aiming at functional coding for low bit rates, as it is currently being investigated in the framework of MPEG-4.

关键词： Stars Detection and tracking algorithms Convolution Motion estimation Distortion Motion models video Computer programming Volume rendering Fourier transforms

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Scanline algorithms in compressed domain

Scanline algorithms in compressed domain

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digital video compression: algorithms and technologies 1996

作者： Shen, Bo Sethi, Ishwar K. Wayne State Univ. Detroit MI USA

ISBN: (纸本)0819420425

The scanline algorithms are popular in a computer graphics for complex geometric manipulations. The main characteristic of the scanline algorithms is that a geometric transformation is decomposed into multiples transforms with each pass operating only along row or column scanlines. This leads to conversion of 2D image manipulation problems to straightforward 1D problems resulting in simple and systematic methods. The goal of this work is to examine the scanline approach for manipulation of transform-compressed images without decompressing them. We show how the scanline algorithms for rotation and projective mapping can be developed for JPEG/DCT images. The performance of the proposed scanline algorithms is evaluated with respect to quality, speed, and control and memory overhead.

关键词： video signal processing

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Burst handling of digital video traffic

Burst handling of digital video traffic

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Proceedings of the 1996 International Conference on Multimedia Computing and Systems

作者： Chiueh, Tzi-cker Wang, Li-chun State Univ of New York at Stony Brook Stony Brook United States

digital video traffic is inherently bursty for two reasons: inherent motion of objects and cameras, and the artifacts of compression algorithms. Because digital video playback requires bandwidth guarantees from the underlying I/O and network systems, the bursty nature of video traffic forces the bandwidth reservations to be made at the level of peak data rates rather than average data rates. This work addresses the burstiness problem in digital video traffic by proposing changes to the MPEG compression/decompression algorithm. The resulting algorithm, block-by-block (BBB) difference coding, successfully minimizes the difference between peak and average bit rates by a factor of 2 to 3 in average, without compromising the compression efficiency, coding speed and video quality.

关键词： video signal processing

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Embedded architecture for noise-adaptive video object detection using parameter-compressed background modeling

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JOURNAL OF REAL-TIME IMAGE PROCESSING 2017年第2期13卷 397-414页

作者： Ratnayake, Kumara Amer, Aishy Concordia Univ Dept Elect & Comp Engn Montreal PQ Canada

video processing algorithms are computationally intensive and place stringent requirements on performance and efficiency of memory bandwidth and capacity. As such, efficient hardware accelerations are inevitable for fast video processing systems. In this paper, we propose resource- and power-optimized FPGA-based configurable architecture for video object detection by integrating noise estimation, Mixture-of-Gaussian background modeling, motion detection, and thresholding. Due to large amount of background modeling parameters, we propose a novel Gaussian parameter compression technique suitable for resource- and power-constraint embedded video systems. The proposed architecture is simulated, synthesized and verified for its functionality, accuracy and performance on a Virtex-5 FPGA-based embedded platform by directly interfacing to a digital video input. Intentional exploitation of heterogeneous resources in FPGAs, and advanced design techniques such as heavy pipelining and data parallelism yield real-time processing of HD-1080p video streams at 30 frames per second. Objective and subjective evaluations to existing hardware-based methods show that the proposed architecture obtains orders of magnitude performance improvements, while utilizing minimal hardware resources. This work is an early attempt to devise a complete video surveillance system onto a stand-alone resource-constraint FPGA-based smart camera.

关键词： Field-programmable gate arrays FPGA video signal processing Noise Moving objects Motion detection Thresholding Gaussian background update Gaussian parameter compression

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Evaluation of lossless compression of teletext and graphics images for TV systems

Evaluation of lossless compression of teletext and graphics ...

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Conference on digital compression technologies and Systems for video Communications

作者： deWith, PHN vanderSchaarMitrea, M PHILIPS RES LABS NL-5656 AA EINDHOVENNETHERLANDS

ISBN: (纸本)0819423564

The diversity in the nature of TV images is increasing due to the mixing of graphics data with natural scenery. In this paper we study the lossless coding of such graphics data with the objective to come to recommendations for video compression of such images. For this purpose, a comparison has been made between contour coding, template coding and run-length coding of graphical imagery. It is concluded that template coding is suitable for TXT-like images but it is not practical for more generic graphics images. For menus and similar imagery, contour and run-length coding provide interesting options.

关键词： TV image compression Teletext graphics contour template run length coding

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The Role of Optical Flow in Automated Quality Assessment of Full-Motion video 40

The Role of Optical Flow in Automated Quality Assessment of ...

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Conference on Applications of digital Image Processing XL

作者： Harguess, Josh Shafer, Scott Marez, Diego Space & Naval Warfare Syst Ctr Pacific 53560 Hull St San Diego CA 92152 USA

ISBN: (数字)9781510612501

ISBN: (纸本)9781510612501;9781510612495

In real-world video data, such as full-motion-video (FMV) taken from unmanned vehicles, surveillance systems, and other sources, various corruptions to the raw data is inevitable. This can be due to the image acquisition process, noise, distortion, and compression artifacts, among other sources of error. However, we desire methods to analyze the quality of the video to determine whether the underlying content of the corrupted video can be analyzed by humans or machines and to what extent. Previous approaches have shown that motion estimation, or optical flow, can be an important cue in automating this video quality assessment. However, there are many different optical flow algorithms in the literature, each with their own advantages and disadvantages. We examine the effect of the choice of optical flow algorithm (including baseline and state-of-the-art), on motion based automated video quality assessment algorithms.

关键词： video Optical flow Image quality video compression Cameras Motion estimation video surveillance Image compression Image processing

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