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IEEE COMMUNICATIONS MAGAZINE 1996年第6期34卷 126-132页

作者： Petajan, E Lucent Technologies Bell Laboratories

Broadcast television in the United States has remained essentially unchanged in the last 50 years except for the addition of color and stereo sound. Today, personal computers are meeting the need for random access of high-resolution images and CD-quality audio. Furthermore, advances in digital video compression and digital communication technology have cleared the way toward offering high-resolution video and audio services to consumers using traditional analog communications channels. In 1987, the U.S. Federal Communications Commission (FCC) chartered an advisory committee to recommend an advanced television system for the United States. From 1990 to 1992, the Advanced Television Test Center (ATTC) tested four all-digital systems, one analog high-definition television (HDTV) system, and one enhancement NTSC system using broadcast and cable television environment simulators. The formation of the HDTV Grand Alliance in May 1993 resulted from the withdrawal of the only analog HDTV system from the competition and a stalemate between the other four all-digital systems. The HDTV Grand Alliance system is composed of the best components from previously competing digital systems demonstrated to the FCC. Moving Pictures Experts Group (MPEG-2) syntax is used with novel encoding techniques to deliver a set of video scanning formats for a variety of applications. This article describes the important features and concepts embodied in the HDTV Grand Alliance system.

关键词： HDTV FCC TV broadcasting video compression System testing digital video broadcasting digital audio broadcasting Microcomputers digital communication Communications technology

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SEGMENTATION OF FRAMES IN A video SEQUENCE USING MOTION AND OTHER ATTRIBUTES

SEGMENTATION OF FRAMES IN A VIDEO SEQUENCE USING MOTION AND ...

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Conference on digital video compression - algorithms and technologies 1995

作者： CHALOM, E BOVE, VM MIT MEDIA LABCAMBRIDGEMA 02139

ISBN: (纸本)0819417661

Motion-compensated video coders typically segment a scene into arbitrary tiles, resulting in a compressed bitstream which is not physically or semantically related to the scene structure. This paper presents a method for segmenting video frames and coding motion of regions, where the regions are defined in terms of a number of different properties. The goal is a video coder which gives good compression while identifying coherent regions in a manner useful for both human users and automated scene-understanding processes. Both a supervised and an unsupervised clustering algorithm are used to segment an image sequence; both algorithms make use of multiple features including motion, texture, position, and color. By utilizing both the structure and motion information, we preserve the semantic/structural content of the different regions, and simultaneously remove the redundancy (in successive frames) by describing the motion information in each region with a six-parameter affine model. In the supervised clustering algorithm, the first frame is manually segmented and used as training data. The classification of subsequent frames is done automatically, by using a MAP estimate, and modeling the n-dimensional feature-space as jointly Gaussian. The unsupervised algorithm is an iterative process that reassigns the classification of each point to the region corresponding to the nearest mean among each region of the segmentation from the previous iteration. In both algorithms, the distance and/or the mean is an n-dimensional measurement, n being the number of features used.

关键词： Image segmentation Optical flow video Motion models video compression Affine motion model Classification systems Image processing algorithms and systems Motion estimation Error analysis

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video CODING WITH WAVELET TRANSFORM ON THE VERY-LOW BIT-RATE COMMUNICATION CHANNEL

VIDEO CODING WITH WAVELET TRANSFORM ON THE VERY-LOW BIT-RATE...

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Conference on digital video compression on Personal Computers: algorithms and technologies

作者： KIM, SW LEE, HK KOREA ADV INST SCI & TECHNOL DEPT COMP SCITAEJON 305701SOUTH KOREA

ISBN: (纸本)0819414824

In this paper, we present a moving image coding system which uses wavelet transform for the videophone on a very low bit rate communication channel (10 K bps PSTN). There are two requirements for our coding system: the good subjective quality for low bit rate coding and the suitability for progressive transmission. To satisfy the requirements, we use multifrequency motion estimation which estimates motion for each frequency bands. After the motion estimation, we can assign less bits to the motion estimation error in the high frequency bands because the human is insensitive to the change in high frequency components in the case of moving image. The experimental results confirm that our approach out-performs discrete cosine transform coding schemes in terms of the subjective quality because there are no blocking effects, and moreover, the wavelet transform in the approach supports the progressive transmission in itself.

关键词： Motion estimation Wavelet transforms Wavelets Image compression video coding video Image processing Image quality video compression Telecommunications

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FEASIBILITY OF video CODEC algorithms FOR SOFTWARE-ONLY PLAYBACK

FEASIBILITY OF VIDEO CODEC ALGORITHMS FOR SOFTWARE-ONLY PLAY...

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Conference on digital video compression on Personal Computers: algorithms and technologies

作者： RODRIGUEZ, AA MORSE, K KALEIDA LABS INC MT VIEWCA 94043

ISBN: (纸本)0819414824

Software-only video codecs can provide good playback performance in desktop computers with a 486 or 68040 CPU running at 33 MHz without special hardware assistance. Typically, playback of compressed video can be categorized into three tasks: the actual decoding of the video stream, color conversion, and the transfer of decoded video data from system RAM to video RAM. By current standards, good playback performance is the decoding and display of video streams of 320 by 240 (or larger) compressed frames at 15 (or greater) frames-per- second. Software-only video codecs have evolved by modifying and tailoring existing compression methodologies to suit video playback in desktop computers. In this paper we examine the characteristics used to evaluate software-only video codec algorithms, namely: image fidelity (i.e., image quality), bandwidth (i.e., compression) ease-of-decoding (i.e., playback performance), memory consumption, compression to decompression asymmetry, scalability, and delay. We discuss the tradeoffs among these variables and the compromises that can be made to achieve low numerical complexity for software-only playback. Frame- differencing approaches are described since software-only video codecs typically employ them to enhance playback performance. To complement other papers that appear in this session of the Proceedings, we review methods derived from binary pattern image coding since these methods are amenable for software-only playback. In particular, we introduce a novel approach called pixel distribution image coding.

关键词： video video compression Computing systems Image compression Image quality Quantization Computer programming Data conversion video coding Binary data

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Flexible VLSI architecture of motion estimator for video image compression

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IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS II-ANALOG AND digital SIGNAL PROCESSING 1996年第6期43卷 467-470页

作者： Nam, SH Lee, MK VLSI and CAD Laboratory Department of Electrical Engineering Yonsei University Seoul South Korea

A linear array architecture for full-search block matching algorithm is proposed, It is suitable for low bit-rate video applications with a single chip realization, It uses a parallel algorithm based on the idea of partial result accumulation, Combining a serial data input with registers for a line of search window pixels and operating on them in parallel, the partial results of the candidate block distortions are obtained for all horizontal search positions, which are successively accumulated into cyclic storage buffer, Based on this scheme, a flexible architecture can be designed for motion vector estimation of different search ranges and block sizes.

关键词： Very large scale integration Motion estimation video compression Image coding Clocks Buffer storage Broadcasting Moon Parallel algorithms Registers

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The Reconfigurable video Coding Standard

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IEEE SIGNAL PROCESSING MAGAZINE 2010年第3期27卷 159-+页

作者： Mattavelli, Marco Amer, Ihab Raulet, Mickael German Univ Cairo Cairo Egypt Inst Elect & Telecommun Rennes Rennes France

More than two decades of research in digital video technologies, together with the emergence of successful international standards for digital video compression, have led to a wide variety of digital video products using video compression for professional and consumer applications. Although many of these video compression standards share common and/or similar coding tools, there is currently no explicit way to exploit such commonalities at the level of the specifications nor at the level of implementations. Moreover, the possibility of taking advantage of the benefits of the continuous improvements of coding technology is only possible by replacing an old standard with a new one. This usually results in the replacement of the existing multimedia devices with new ones capable of handling the new deployed standards. Such necessity is not always well accepted by the public and professionals for obvious reasons.

关键词： video coding video compression Automatic voltage control Technological innovation Standardization Signal processing algorithms video sharing MPEG standards Codecs ISO standards

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MULTIPLICATION FREE SCALED 8X8 DCT ALGORITHM WITH 530 ADDITIONS

MULTIPLICATION FREE SCALED 8X8 DCT ALGORITHM WITH 530 ADDITI...

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Conference on digital video compression - algorithms and technologies 1995

作者： KASPEROVICH, L MOSCOW SPACE RES INST MOSCOW 117810RUSSIA

ISBN: (纸本)0819417661

The known idea of the rational DCT computations employs multiply approximation, where overall accuracy is not affected due to the rounding-off and truncations, which are intrinsic to the quantization process in the image/video compression. Besides higher computational efficiency, the multiplication free scheme can take advantage of the full-length processor word of 32-bit or newest 64-bit microprocessors, being applied to the packed pixel pairs. In this paper we propose the scaled DCT algorithm, that uses 30 `essential' multiplications by (root)2 and 64 `non-essential' by three constants (which are closed to 5, 3 and 2). The number of additions in the approximation version of the algorithm is considerably fewer than in the known multiplication free 8 X 8 DCT computational scheme. Other advantage of the algorithm is its symmetry, i.e. almost all the computational modules used in both forward and inverse DCT implementations are the same rather than transpositional ones. A performance of the software implementations of MJPEG codec for Pentium PC, based on the algorithm presented, as well as its applicability to the high resolution software-only playback in various video standards, is also discussed.

关键词： video Quantization Image compression Multimedia Semantic video video compression Algorithm development Image processing LCDs Matrices

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FORWARD ADAPTIVE QUANTIZATION WITH OPTIMAL OVERHEAD COST FOR IMAGE AND video CODING WITH APPLICATIONS TO MPEG video CODERS

FORWARD ADAPTIVE QUANTIZATION WITH OPTIMAL OVERHEAD COST FOR...

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Conference on digital video compression - algorithms and technologies 1995

作者： ORTEGA, A RAMCHANDRAN, K UNIV SO CALIF DEPT EE SYST & SIGNALLOS ANGELESCA 90089

ISBN: (纸本)0819417661

We address the problem of optimal forward-adaptive quantization in the video and image coding framework. In this framework, as is consistent with that of most practical coders like MPEG, the encoder has the capability of changing the quantizer periodically (e.g. at a macroblock interval in MPEG). In this paper, we formulate an optimal strategy, based on dynamic programming, for updating the quantizer choice for coding an image or video signal. While in some coding environments the overhead needed to specify the quantizer used by each block is equal for every choice of quantizer, in other situations (e.g. MPEG) the overhead cost is higher if the quantizer changes from one block to the next. We concentrate on the latter case which will be more likely encountered in situations where the overhead represents a significant fraction of the overall rate, as can be the case if a low bit rate is used (e.g. error frames in a typical motion-compensated video coder). We provide empirical evidence of the performance gain that can be obtained when applying our optimal algorithm to typical motion-compensated prediction error frames in MPEG, showing how the popular Viterbi algorithm can be used to find the optimal solution.

关键词： IMAGE compression video compression MPEG OVERHEAD BIT ALLOCATION QUANTIZATION

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MPEG-4 video verification model: A video encoding/decoding algorithm based on content representation

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SIGNAL PROCESSING-IMAGE COMMUNICATION 1997年第4期9卷 367-384页

作者： Ebrahimi, T Signal Processing Laboratory Swiss Federal Institute of Technology — EPFL CH-1015 Lausanne Switzerland

MPEG-4 video aims at providing standardized core technologies allowing efficient storage, transmission and manipulation of video data in multimedia environments. This is a challenging task given the broad spectrum of requirements and applications in multimedia. In order to achieve this broad goal, rather than a solution for a narrow set of applications, functionalities common to clusters of applications are under consideration. Therefore, video group activities in MPEG-4 aim at providing solutions in the form of tools and algorithms enabling functionalities such as efficient compression, object scalability, spatial and temporal scalability, and error resilience. The standardized MPEG-4 video will provide a toolbox containing tools and algorithms bringing solutions to the above-mentioned functionalities and more. The current focus of the MPEG-4 video group is the development of the video Verification Models. A Verification Model (VM) is a common platform with a precise definition of encoding and decoding algorithms which can be presented as tools addressing specific functionalities. It evolves through time by means of core experiments. New algorithms/tools are added to the VM and old algorithms/tools are replaced in the VM by successful core experiments. Until October 1996, the MPEG-4 video group has focused its efforts on a single VM which has gradually evolved from version 1.0 to version 4.0, and in the process has addressed increasing number of desired functionalities, namely, content based object and temporal scalabilities, spatial scalability, error resilience, and compression efficiency. This paper gives an overview of version 4.0 of the video VM in MPEG-4. In doing so, issues, algorithms, and majors tools used in the development of this future video standard are discussed. (C) 1997 Elsevier Science B.V.

关键词： video coding content based coding object based coding region based coding

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VOLUME DATA compression USING SMOOTHED PARTICLE TRANSFORMATION

VOLUME DATA COMPRESSION USING SMOOTHED PARTICLE TRANSFORMATI...

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Conference on digital video compression - algorithms and technologies 1995

作者： NAGASAWA, M HITACHI CRL ULTRA HIGH SPEED NETWORK & COMP TECHNOL LABSTOKYO 185JAPAN

ISBN: (纸本)0819417661

In 3D entertainment oriented games, most geometrical objects are represented by polygon sets. Thus, the handling of polygons is highly optimized in the hardware of graphic workstations. However, 3D scientific simulations do not ordinarily use polygon data but rather volume data in its original form, such as the scalar array p(x,y,z). If we had an effective volume data compression algorithm and a standard way of representing this data, it could be used in a more efficient manner in the network environment. This paper presents a Smoothed Particle Transformation (SPT) algorithm for volume data at several levels of compressed resolution from an original array description of a given variable. Representing data at various levels of detail is important for archiving the huge data in the network environment. SPT contributes not only to data compression but also for resolution rearrangement. As a result, it speeds up of the visualization of transferred data, especially for the direct volume rendering of compressed data.

关键词： compression TRANSFORMATION VOLUME DATA

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