In a sign-magnitude representation of binary lattice codevectors, only a few least significant bit-planes are constrained due to the structure of the lattice, while there is no restriction on other more significant bi...
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In a sign-magnitude representation of binary lattice codevectors, only a few least significant bit-planes are constrained due to the structure of the lattice, while there is no restriction on other more significant bit-planes. Hence, any convenient bit-plane coding method can be used to encode the lattice codevectors, with modification required only for the lattice-defining, least-significant bit-planes. Simple encoding methods for the lattice-defining bit-planes of the D-4, RE8, and Barnes-Wall 16-dimensional lattices are described. Simulation results for the encoding of a uniform source show that standard bit-plane coding together with the proposed encoding provide about the same performance as integer lattice vector quantization when the bit-stream is truncated. When the entire bit-stream is fully decoded, the granular gain of the lattice is realized.
A perceptually enhanced prioritized bit-plane audio coding algorithm is presented in this paper. According to the energy distribution in different frequency regions, the bit-planes are prioritized with optimized param...
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A perceptually enhanced prioritized bit-plane audio coding algorithm is presented in this paper. According to the energy distribution in different frequency regions, the bit-planes are prioritized with optimized parameters. Based on the statistical modeling of the frequency spectrum, a much more simplified implementation of prioritized bit-plane coding is integrated with the recent release of MPEG-4 scalable lossless (SLS) audio coding structure by replacing the sequential bit-plane coding in the enhancement layer. With zero extra side information, trivial added complexity, and modification to the original SLS structure, extensive experimental results show that the perceptual quality of SLS with noncore and very low core bit-rate is improved significantly in a wide range of bit-rate combinations. Fully scalable audio coding up to lossless with much enhanced perceptual quality is thus achieved.
In this paper, we propose a new efficient bit-plane coding method for fine granular scalable (FGS) video coding. The general structure of the proposed bit-plane coding method is based on the traditional bit-plane codi...
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In this paper, we propose a new efficient bit-plane coding method for fine granular scalable (FGS) video coding. The general structure of the proposed bit-plane coding method is based on the traditional bit-plane coding scheme in MPEG-4 FGS. However, to enhance coding efficiency of bit-plane encoding, we apply an efficient probability estimation scheme through employing the binary arithmetic coding. For probability estimation, various context models are designed to take advantage of the characteristics of each bit-plane as well as the correlations of symbols among different bit-planes. Experimental results show that the proposed FGS coding scheme provides better coding performance, compared to the well-known FGS coding schemes in MPEG-4 FGS and JSVM. (c) 2006 Wiley Periodicals, Inc.
In this paper, we propose a new efficient entropy coding scheme, namely context-based binary arithmetic coding for bit-plane coding (CBACBP), for the enhancement layer of fine granular scalable (FGS) video coding. The...
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In this paper, we propose a new efficient entropy coding scheme, namely context-based binary arithmetic coding for bit-plane coding (CBACBP), for the enhancement layer of fine granular scalable (FGS) video coding. The basic structure of proposed CBACBP is based on the traditional bit-plane coding of MPEG-4 FGS. However, in order to enhance the coding efficiency of bit-plane coding, a newly designed context-based binary arithmetic coding scheme is used. In CBACBP, we apply three types of probability estimation techniques.. The first type relies on local information of a given symbol to code, such as bit-plane level, data level and frequency component. In the second type, the preceding symbols in the same and/or higher bit-planes are used. In the third type, we consider complexity of a block including the symbol based on the number of coded nonzero coefficients in the block. Experimental results show that the proposed CBACBP improves the PSNR up to 1.2 and 0.5 dB compared with MPEG4 FGS and JSVM, respectively.
In this paper, we propose a low complexity prioritized bit-plane coding scheme to improve the rate-distortion performance of cyclical block coding in MPEG-21 scalable video coding. Specifically, we use a block priorit...
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ISBN:
(纸本)0819459763
In this paper, we propose a low complexity prioritized bit-plane coding scheme to improve the rate-distortion performance of cyclical block coding in MPEG-21 scalable video coding. Specifically, we use a block priority assignment algorithm to firstly transmit the symbols and the blocks with potentially better rate-distortion performance. Different blocks are allowed to be coded unequally in a coding cycle. To avoid transmitting priority overhead, the encoder and the decoder refer to the same context to assign priority. Furthermore, to reduce the complexity, the priority assignment is done by a look-up-table and the coding of each block is controlled by a simple threshold comparison mechanism. Experimental results show that our prioritized bit-plane coding scheme can offer up to 0.5dB PSNR improvement over the cyclical block coding described in the joint scalable verification model (JSVM).
Wide bitrate range scalability is now the latest trend in audio coding. A lot of efforts has been devoted to the development of algorithms for more efficient scalable audio coder that scales from very low bitrate. Sca...
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ISBN:
(纸本)9780769527468
Wide bitrate range scalability is now the latest trend in audio coding. A lot of efforts has been devoted to the development of algorithms for more efficient scalable audio coder that scales from very low bitrate. Scalable audio coding technique such as MPEG-4 Scalable Lossless coding (SLS) offers a unified solution for high-compression perceptual audio and high-quality lossless audio. SLS provides a fine-grain scalable extension of the well-known MPEG-4 Advanced Audio coding (AAC) perceptual audio coder, up to fully. lossless reconstruction. Recently, the combination of SLS and AAC coder is renamed as "High Definition Advanced Audio coding" (HD-AAC). It is observed that HD-AAC can be further improved at intermediate enhancement bitrate when the core bitrate is low. In this paper, a Perceptually Prioritized bit-plane coding (PPBPC) is proposed. With this novel coding scheme, the bit-plane coding is performed with priorities according to the perceptual information of the signal to be coded. By using this low-complexity structure with trivial extra side information, the bit-plane coding for scalable audio can be implemented in a perceptually more efficient manner and the quality of the audio under aforementioned scenario is greatly improved.
An innovative embedded algorithm based on context model using neighboring coefficients and parent coefficients is proposed, which can implement real-time image processing and can achieve high fidelity. By analyzing th...
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ISBN:
(纸本)9781424434824
An innovative embedded algorithm based on context model using neighboring coefficients and parent coefficients is proposed, which can implement real-time image processing and can achieve high fidelity. By analyzing the algorithm and implementation, it is found that the wavelet transform and bit-plane prediction have a great perplexity which can not be implemented efficiently. Based on multiple DSP hardware platforms, a architecture using parallelism and pipelining technology is present, which can reduce computation complexity and improve encoding efficiency. Experiment results show that the algorithm can achieve higher performance than JPEG2000 in terms of image quality and operating speed.
This thesis studies lattice vector quantization (LVQ) with application to audio and im- age sources. The performance of nonzero pulse amplitude quantization implicit in alge- braic codebook code-excited linear predict...
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This thesis studies lattice vector quantization (LVQ) with application to audio and im- age sources. The performance of nonzero pulse amplitude quantization implicit in alge- braic codebook code-excited linear prediction (ACELP) is examined and it is demonstrated that the quantization used in ACELP is effective in a rate-distortion sense at the encoding rates commonly used. A block-based Gaussian mixture model (GMM) is used to model the marginal distribution and the block energy distribution of transform audio data. The expectation-maximization algorithm is used to estimate the GMM parameters. A GMM- based rate-distortion function is derived and shown to closely match the observed spherical LVQ performance. Then, we move forward to the lattice VQ on transformed image. The GMM is used to motivate a subband image coding algorithm based on lattice-based spher- ical VQ and lattice-based pyramid VQ. The algorithm partitions a subband image into blocks of various sizes, depending on their energy and complexity constraints on the enu- meration encoding of lattice codevectors. Using the cubic lattice, the algorithm provides performance competitive with the set partitioning in hierarchical trees (SPIHT) algorithm. A bit-plane coding method is developed for the encoding of binary lattice codevectors as binary codewords, yieldingan embedded bitstream. In sign-magnituderepresentation, only a few least significant bit-planes are constrained due to the structure of the lattice, while there is no restriction on other more significant bit-planes. Simple encoding methods for the lattice-defining bit-planes of the D4, RE8, and Barnes-Wall 16-dimensional lattices are described. Simulation results for these lattices show that partial decoding of the resulting embedded bitstream provides about the same performance as for the integer lattice. When the entire bitstream is fully decoded, the granular gain of the lattice is realized.
For bit-plane coding of random source, we establish a relationship between the probability density function of an arbitrary non-negative distribution and the bit-plane symbol probability. Applied to Laplacian source, ...
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ISBN:
(纸本)9781424442966
For bit-plane coding of random source, we establish a relationship between the probability density function of an arbitrary non-negative distribution and the bit-plane symbol probability. Applied to Laplacian source, the relationship gives a simple, closed form of bit-plane symbol probability, which is a superset of the probability assignment rule adopted in the MPEG-4 Audio Scalable Lossless coding (SLS) international standard. For bit-plane arithmetic coding of Laplacian source, we propose an algorithm and apply it to MPEG-4 SLS. Experimental results show that without changing the encoder/decoder complexity, the proposed algorithm consistently improved the compression ratio over SLS for all the 51 MPEG test sequences. The overall improvement in the compression ratio is 0.11%.
For bit-plane coding of random source, we establish a relationship between the probability density function of an arbitrary non-negative distribution and the bit-plane symbol probability. Applied to Laplacian source, ...
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ISBN:
(纸本)9781424442959
For bit-plane coding of random source, we establish a relationship between the probability density function of an arbitrary non-negative distribution and the bit-plane symbol probability. Applied to Laplacian source, the relationship gives a simple, closed form of bit-plane symbol probability, which is a superset of the probability assignment rule adopted in the MPEG-4 Audio Scalable Lossless coding (SLS) international standard. For bit-plane arithmetic coding of Laplacian source, we propose an algorithm and apply it to MPEG4 SLS. Experimental results show that without changing the encoder/decoder complexity, the proposed algorithm consistently improved the compression ratio over SLS for all the 51 MPEG test sequences. The overall improvement in the compression ratio is 0.11percent.
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