In scalable audio coders, such as the MPEG-4 SLS, error-mapping is used to map quantization errors in the core coder to an error signal before passing through bit-plane coding. In this paper, we propose a new error-ma...
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ISBN:
(纸本)9781479958962
In scalable audio coders, such as the MPEG-4 SLS, error-mapping is used to map quantization errors in the core coder to an error signal before passing through bit-plane coding. In this paper, we propose a new error-mapping scheme that is derived by observing statistical properties of the error signal. Compared with the error-mapping in SLS, the proposed scheme improves coding efficiency as well as computational complexity of the coder. An average improvement of 9 points in MUSHRA score has been achieved by the proposed scheme in subjective listening tests. The proposed error-mapping adds a useful new tool to the existing toolset for constructing next-generation scalable audio coders.
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.
Recently the wavelet-based contourlet transform (WBCT) is adopted for image coding because it matches better image textures of different orientations. However, its computational complexity is very high. In this paper,...
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Recently the wavelet-based contourlet transform (WBCT) is adopted for image coding because it matches better image textures of different orientations. However, its computational complexity is very high. In this paper, we propose three tools to enhance the WBCT coding scheme, in particular, on reducing its computational complexity. First, we propose short-length 2-D filters for directional transform. Second, the directional transform is applied to only a few selected subbands and the selection is done by a mean-shift-based decision procedure. Third, we fine-tune the context tables used by the arithmetic coder in WBCT coding to improve coding efficiency and to reduce computation. Simulations show that, at comparable coded image quality, the proposed scheme saves over 92% computing time of the original WBCT scheme. Comparing to the conventional 2-D wavelet coding schemes, it produces clearly better subjective image quality. (c) 2012 Elsevier Inc. All rights reserved.
A lossless compression algorithm for synthetic aperture radar (SAR) amplitude images based on modified quadtree bit-plane coding is proposed. First, a SAR amplitude image is divided into independent bitplanes, and th...
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A lossless compression algorithm for synthetic aperture radar (SAR) amplitude images based on modified quadtree bit-plane coding is proposed. First, a SAR amplitude image is divided into independent bitplanes, and then, the probability of bit "0" is computed and compared with the predefined threshold in order to select the optimal block size for each bitplane. Finally, a modified quadtree coding method is adopted to encode each block data. Additionally, the computing method of predefined threshold is also addressed in this letter. The experimental results show that the proposed method outperforms previous methods for all SAR images of the test sets;an average 0.895-bpp decrease in bit rate was observed when compared with JPEG-LS.
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.
Image segmentation is an important task in many image processing systems. For efficient transmission over a band-limited channel, original images are often compressed before being stored in databases. In order to avoi...
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Image segmentation is an important task in many image processing systems. For efficient transmission over a band-limited channel, original images are often compressed before being stored in databases. In order to avoid the burden of decompressing an image, it is desirable to extract features directly from a code stream. This approach saves computational time significantly. The look up table used for the MQ coder defined in joint photographic expert group 2000 (JPEG2000) called the MQ table provides probability models for bit-plane coding of wavelet coefficients, the wavelet histogram information can be obtained directly from a JPEG2000 code stream. Thus, the MQ feature based on the MQ table is proposed to segment an image in the JPEG2000 domain directly. Experimental results of clustering these features by using the simple K-means algorithm show the potential of MQ feature.
In this paper, we propose a joint source-channel coding (JSCC) scheme for image transmission over wireless channel. In the scheme, fountain codes are integrated into bit-plane coding for channel coding. Compared to tr...
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ISBN:
(纸本)9780819485762
In this paper, we propose a joint source-channel coding (JSCC) scheme for image transmission over wireless channel. In the scheme, fountain codes are integrated into bit-plane coding for channel coding. Compared to traditional erasure codes for error correcting, such as Reed-Solomon codes, fountain codes are rateless and can generate sufficient symbols on the fly. Two schemes, the EEP (Equal Error Protection) scheme and the UEP (Unequal Error Protection) scheme are described in the paper. Furthermore, the UEP scheme performs better than the EEP scheme. The proposed scheme not only can adaptively adjust the length of fountain codes according to channel loss rate but also reconstruct image even on bad channel.
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.
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.
In this paper, we propose a novel compression scheme for medical images with extended bit depth. Our scheme efficiently utilizes the VOI (value of interest) settings of the medical images, so that only a small part of...
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ISBN:
(纸本)9781424456536
In this paper, we propose a novel compression scheme for medical images with extended bit depth. Our scheme efficiently utilizes the VOI (value of interest) settings of the medical images, so that only a small part of the coded bit-stream is needed at the decoder to lossless display the original image with recommended VOI parameters. Gray-Golomb coding is used to support VOI progressive transmission. In addition, the pixel domain bit-plane coding enables accurate distortion estimation at pixel level for any truncated bit-stream. Compared to JPEG2000, our scheme achieves much higher VOI performance with very slight overall bit-rate increase.
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