In this paper, we present a new embedded video coding system with local motion compensation. An invertible motion compensated3-dsubband filter bank is utilized for video analysis/synthesis. The efficient embedded im...
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In this paper, we present a new embedded video coding system with local motion compensation. An invertible motion compensated3-dsubband filter bank is utilized for video analysis/synthesis. The efficient embedded image coding scheme EZBC is extended to 3-dcoding of video subbands. The coded bitstream is rate scalable and fully embedded thus meeting the increasing need for fine granular scalability in video streaming applications. Our experimental results show the new algorithm outperforms nonscalable standard MPEG-2 by 0.8-3.3dB (luminance component) over a broad range of bitrates, while providing an embedded video bitstream. Unlike conventional SNR hybrid coders, this multirate property is achieved without a loss in compression efficiency. Comparisons are also made to two other competing embedded video coders, LZC and Sd-SPIHT, both based on 3-d subband coding as well. The new coder demonstrates a significant advantage for encoding video with high local motion content, thanks to the efficient inclusion of local motion information in the temporal filter bank of our proposed system. (C) 2001 Published by Elsevier Science B.V.
This paper presents a new 3-d subband coding framework that is able to achieve a good balance between high compression performance and channel error resilience. Various data transform methods for the decorrelation of ...
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This paper presents a new 3-d subband coding framework that is able to achieve a good balance between high compression performance and channel error resilience. Various data transform methods for the decorrelation of video were examined and compared, including subband filtering, discrete cosine transforms, discrete wavelet transforms, and lapped transforms. The coding stage of the algorithm is based on a generalized adaptive quantization framework, which is applied to the 3-d transformed coefficients. More specifically, it features a simple coding structure based on quadtree coding and lattice vector quantization techniques. In typical applications, good performance at high compression ratios is obtained often without entropy coding. Furthermore, because temporal decorrelation is absorbed by the transform, traditional motion compensated prediction becomes not necessary, which results in a significant computational advantage over standard video coders. The error-resilience feature Is achieved through classifying the compresseddata streams into separated sub-streams with different error sensitivity levels. This enables a good adaptation to different channel models according to their noise statistics and error-protection protocols. Experimental results have shown that the subband video coder is able to achieve highly competitive performance relative to MPEG-2 in both noiseless and noisy environments. Furthermore, lapped transforms are shown experimentally to outperform the other transforms in the 3-dsubband environment. The subbandcoding framework provides a practical solution for video communications over wireless channels, where efficiency, error resilience, and computational simplicity are vital in providing superior quality of service.
The authors present a wavelet tree-based video coding system, which is referred to as three-dimensional (3-d) backwardcoding of wavelet trees (BCWT). The 3-d BCWT algorithm encodes the wavelet trees from the lowest w...
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The authors present a wavelet tree-based video coding system, which is referred to as three-dimensional (3-d) backwardcoding of wavelet trees (BCWT). The 3-d BCWT algorithm encodes the wavelet trees from the lowest wavelet level to the highest wavelet level. All the coding steps for each wavelet coefficient are finishedduring one coding pass, which makes this algorithm very efficient. The coding process of the 3-d BCWT algorithm is subband by subband, so that a coefficient will be encoded only after all the coefficients in the next lower-level wavelet subbands have been encoded. The output bitstream of the encoder is therefore layered according to the wavelet level. The implementation results show that the 3-d BCWT algorithm has almost identical rate distortion performance to the well-known 3-d set partitioning in hierarchical trees (SPIHT) algorithm. However, it is computationally more efficient and uses significantly less memory than the 3-d SPIHT algorithm. (C) 2012 Society of Photo-Optical Instrumentation Engineers (SPIE). [dOI: 10.1117/***.51.4.047403]
The conventional approach of using dCT (discrete cosine transform) which is Fourier based has been most popular in industry. The advantages and potentials of image compression using wavelet analysis are now being expl...
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ISBN:
(纸本)0819428361
The conventional approach of using dCT (discrete cosine transform) which is Fourier based has been most popular in industry. The advantages and potentials of image compression using wavelet analysis are now being explored. In this paper a neu image compression algorithm based on wavelet analysis is presented that makes use of a lifting scheme and a modification of the 3-d subband coding. The exploitation of contexts in both space-time and space-space brings out an improved algorithm that is both performance effective and computationally efficient. The software system using this algorithm has the advantage that it is much more flexible and less costly than hardware systems. The new algorithm has been tested with the compression of traffic scene video with satisfactory results.
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