An error corruption model (ECM) to describe the interframe error propagation phenomenon in a motion-compensated predictive video codec using fluid flow characteristics is proposed. First, we derive a diffusion differe...
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An error corruption model (ECM) to describe the interframe error propagation phenomenon in a motion-compensated predictive video codec using fluid flow characteristics is proposed. First, we derive a diffusion differential equation and discuss its solution, which captures the damping effect of error propagation. Then, we propose a tracking quadrilateral (TQ) mechanism to capture the shaping and drilling effects of error propagation. Finally, we integrate these building blocks to form an adaptive fluid-based ECM (F-ECM). The accuracy of the proposed F-ECM is verified by experimental results.
Compressed video sequences are very vulnerable to channel disturbances when they are transmitted through a packet loss networks. The predictive video encoders are very efficient but even a single packet loss can cause...
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Compressed video sequences are very vulnerable to channel disturbances when they are transmitted through a packet loss networks. The predictive video encoders are very efficient but even a single packet loss can cause decoding error propagation through all the frames following the erasure. An approach to tackle this problem is applying multiple description coding (MDC) techniques. Another important issue in robust video transmission is the problem of error-recovery. In fact it is necessary applying an error-concealment (EC) strategy in order to reconstruct the information lost during the transmission. In this paper we deal with sequence-based EC algorithm that performs the error-recovery by using the information coming from a certain number of frames in the future to minimize the effect of error propagation. Target of this work is to apply such EC strategy to a balanced MD coding system. Simulation results show the great improvement that a sequence-based EC algorithm can give to a BMDC system.
Compressed video bit stream is very sensitive to transmission errors. There exist many error-resilient techniques that can significantly improve the reconstructed video quality by reducing the spatiotemporal error pro...
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ISBN:
(纸本)078038251X
Compressed video bit stream is very sensitive to transmission errors. There exist many error-resilient techniques that can significantly improve the reconstructed video quality by reducing the spatiotemporal error propagation. In this paper, an error-resilient coding scheme that can decrease the spatial error propagation with little overhead is proposed. It disables intra AC prediction and groups appropriate fixed length coded (FLC) syntaxes in a video packet (or slice) together to form a new partition. With intra AC prediction disables, errors occurred in these FLC syntaxes do not cause spatial error propagation. We evaluate the efficiency of the error-resilient coding scheme by comparing the reconstructed PSNR of the proposed coding scheme with that of the MPEG-4 coding scheme over the AWGN channel and the Rayleigh channel.
In this paper, we propose a switching adaptive predictor (FSWAP) with run-length encoding for lossless image coding. The proposed FSWAP system has two operation modes; run mode and regular mode. If the members in the ...
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In this paper, we propose a switching adaptive predictor (FSWAP) with run-length encoding for lossless image coding. The proposed FSWAP system has two operation modes; run mode and regular mode. If the members in the texture context of the coding pixel have identical grey values, the run mode is used, otherwise the regular mode is used. The run mode, using run-length coding, with an arithmetic coder, is very useful for images with flat regions. The regular mode borrows the switching predictor structure in SWAP (Lih-Jen Kau et al, IEEE Trans. Fuzzy Systems) with some modifications. Experiments show that simplified context clustering is very useful in error modeling for prediction refinement. Furthermore, the execution time of FSWAP can be accelerated with minor degradation in the bit rates associated with the modifications. Comparisons of the proposed system to existing state-of-the-art predictive coders are given to demonstrate its coding efficiency
Compressed video streams are very exposed to channel losses when they are transmitted through an unreliable network. The predictive encoding scheme is efficient but even a single packet loss can cause decoding error p...
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Compressed video streams are very exposed to channel losses when they are transmitted through an unreliable network. The predictive encoding scheme is efficient but even a single packet loss can cause decoding error propagation through all the frames following the erasure. An error-resilience approach to tackle this problem is the multiple description coding (MDC) technique. Another important issue connected to this approach is the problem of the error-concealment (EC) used to reconstruct the information lost during the transmission. In this paper, we deal with a sequence-based EC algorithm that performs the error-concealment by using the information coming from a certain number of frames in the future to minimize the effect of error propagation. The target of this work is applying such an EC strategy to a balanced MDC system. Simulation results show the great improvement that a sequence-based EC algorithm can give compared to classical EC approaches.
A robust speech feature extraction procedure, by kernel regression nonlinear predictive coding, is presented. Features maximally insensitive to additive noise are obtained by growth transformation of regression functi...
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A robust speech feature extraction procedure, by kernel regression nonlinear predictive coding, is presented. Features maximally insensitive to additive noise are obtained by growth transformation of regression functions spanning a reproducing kernel Hilbert space (RKHS). Experiments on TI-DIGIT demonstrate consistent robustness of the new features to noise of varying statistics, yielding significant improvements in digit recognition accuracy over identical models trained using Mel-scale cepstral features and evaluated at noise levels between 0 and 30 dB SNR.
In this paper, we investigate a two-stage near-lossless compression scheme. It is in the spirit of "lossy plus residual coding" and consists of a wavelet-based lossy layer followed by an arithmetic coding of...
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In this paper, we investigate a two-stage near-lossless compression scheme. It is in the spirit of "lossy plus residual coding" and consists of a wavelet-based lossy layer followed by an arithmetic coding of the quantized residual to guarantee a given L/sup /spl infin// error bound in the pixel domain. Our focus is on the selection of the optimum bit rate for the lossy layer to achieve the minimum total bit rate. Unlike other similar lossy plus lossless approaches using a wavelet-based lossy layer, the proposed method does not require iteration of decoding and the IWT(Inverse Wavelet Transform) to locate the optimum bit rate. We propose a simple method to estimate the optimal bit rate and provide a theoretical justification for it. It is based on the 'critical rate' argument from the Rate-Distortion theory and 'whiteness' of the residual.
Motion estimation is the most time-consuming module in any video coding standard. Existing block-matching algorithms (BMA) reduce the search time of the motion estimation process with moderate loss in quality. In this...
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Motion estimation is the most time-consuming module in any video coding standard. Existing block-matching algorithms (BMA) reduce the search time of the motion estimation process with moderate loss in quality. In this paper, a novel block-matching algorithm for fast motion estimation namely direct ion-based block-matching algorithm (DBM) is proposed. Existing BMA initiate its search from the center of the search area for every frame, which is time consuming. The proposed algorithm utilizes the temporal correlation in the motion vectors between successive frames to reduce the search time. The motion vectors of the previous frame imply the direction of motion in the succeeding frames thus minimizing the search domain. Experimental results show that DBM provides faster searching with moderate to low distortion compared to existing BMA.
Subband video coding is an elegant scheme to fulfill high performance scalable video coding. In this paper, a new update scheme, energy distributed update steps (EDU), is proposed for the temporal transform in lifting...
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ISBN:
(纸本)0780385543
Subband video coding is an elegant scheme to fulfill high performance scalable video coding. In this paper, a new update scheme, energy distributed update steps (EDU), is proposed for the temporal transform in lifting based motion compensated video coding. The idea is to update where predict is made by distributing high-pass signals to the low-pass frame. The scheme avoids complex and inaccurate inversion of the motion information that used in the traditional update steps, thus it reduces computations in temporal transform. Experimental results show that the coding performances can be improved up to 0.77 dB.
We propose a new scheme for compressing on image set by building its minimal-cost prediction structure. Existing prediction-based video coding methods can be easily extended and incorporated into this scheme to achiev...
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We propose a new scheme for compressing on image set by building its minimal-cost prediction structure. Existing prediction-based video coding methods can be easily extended and incorporated into this scheme to achieve higher compression efficiency. According to this prediction structure, we also develop a progressive transmission approach for interactive object movie (OM) browsing.
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