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A context adaptive bit-plane coder with maximum-likelihood-based stochastic bit-reshuffling technique for scalable video coding

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IEEE TRANSACTIONS ON MULTIMEDIA 2006年第4期8卷 654-667页

作者： Peng, Wen-Hsiao Chiang, Tihao Hang, Hsueh-Ming Lee, Chen-Yi Natl Chiao Tung Univ Dept Elect Engn Hsinchu 30010 Taiwan

In this paper, we propose a context adaptive bit-plane coding (CABIC) with a stochastic bit reshuffling (SBR) scheme to deliver higher coding efficiency and better subjective quality for fine granular scalable (FGS) video coding. Traditional bit-plane coding in FGS algorithm suffers from poor coding efficiency and subjective quality. To improve coding efficiency, our CABIC constructs context models based on both the energy distribution in a block and the spatial correlations in the adjacent blocks. Moreover, it exploits the context across bit-planes to save side information. To improve subjective quality, our SBR reorders the coefficient bits by their estimated rate-distortion performance. Particularly, we model transform coefficients with Laplacian distributions and incorporate them into the context probability models for content-aware parameter estimation. Moreover, our SBR is implemented with a dynamic priority management that uses a low-complexity dynamic memory organization. Experimental results show that our CABIC improves the PSNR by 0.5 similar to 1.0 dB at medium and high bit rates. While maintaining similar or even higher coding efficiency, our SBR improves the subjective quality.

关键词： bit-plane coding fine granularity scalability scalable video coding

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A Lossless Compression Algorithm for SAR Amplitude Imagery Based on Modified Quadtree coding of bit plane

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IEEE GEOSCIENCE AND REMOTE SENSING LETTERS 2010年第4期7卷 723-726页

作者： Pan, Zhigang Gao, Xin Sun, Xiumin Song, Hongmei Chinese Acad Sci Inst Elect Beijing 100190 Peoples R China Chinese Acad Sci Grad Univ Beijing 100049 Peoples R China

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 bit planes, 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 bit plane. 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.

关键词： bit-plane coding lossless compression quadtree coding synthetic aperture radar (SAR)

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NEW bit-plane PROBABILITY CALCULATIONS FOR SCALABLE TO LOSSLESS AUDIO coding

NEW BIT-PLANE PROBABILITY CALCULATIONS FOR SCALABLE TO LOSSL...

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IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP)

作者： Movassagh, Mahmood Kabal, Peter McGill Univ Dept Elect & Comp Engn Montreal PQ Canada

ISBN: (纸本)9781479928934

Considering the properties of the residual signal, core-based bit-plane probabilities are provided for MPEG-4 Audio Scalable to Lossless coding (SLS), which matches the quantization and coding performed in the core layer. Using the same strategy, new probabilities are obtained to consider the clipping effect in bit-plane coding of an unbounded signal, which is useful for non-core mode of SLS coding. Simulations show that considering the core layer parameters and the clipping effect improve the bit-plane probabilities estimation compared to the existing method.

关键词： Scalable Audio coding Quantization bit-plane coding Arithmetic coding AAC SLS

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NEW bit-plane PROBABILITY CALCULATIONS FOR SCALABLE TO LOSSLESS AUDIO coding

NEW BIT-PLANE PROBABILITY CALCULATIONS FOR SCALABLE TO LOSSL...

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IEEE International Conference on Acoustics, Speech and Signal Processing

作者： Mahmood Movassagh Peter Kabal Department of Electrical and Computer Engineering McGill University Montreal Canada

ISBN: (纸本)9781479928941

关键词： Audio bit-plane coding Selective laser sintering CORE LAYER Quantization Probability clipping Line clipping Lossless lossless coding lossless compression residual signal

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bit-stream allocation methods for scalable video coding supporting wireless communications

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SIGNAL PROCESSING-IMAGE COMMUNICATION 2007年第3期22卷 298-316页

作者： Zgaljic, Toni Sprljan, Nikola Izquierdo, Ebroul Univ London Queen Mary Dept Elect Engn Multimedia & Vis Grp London England

The demand for video access services through wireless networks, as important parts of larger heterogeneous networks, is constantly increasing. To cope with this demand, flexible compression technology to enable optimum coding performance, especially at low bit-rates, is required. In this context, scalable video coding emerges as the most promising technology. A critical problem in wavelet-based scalable video coding is bit-stream allocation at any bit-rate and in particular when low bit-rates are targeted. In this paper two methods for bit-stream allocation based on the concept of fractional bit-planes are reported. The first method assumes that minimum rate-distortion (R-D) slope of the same fractional bit-plane within the same bit-plane across different subbands is higher than or equal to the maximum R-D slope of the next fractional bit-plane. This method is characterised by a very low complexity since no distortion evaluation is required. Contrasting this approach, in the second method the distortion caused by quantisation of the wavelet coefficients is considered. Here, a simple yet effective statistical distortion model that is used for estimation of R-D slopes for each fractional bit-plane is derived. Three different strategies are derived from this method. In the first one it is assumed that the used wavelet is nearly orthogonal, i.e. the distortion in the transform domain is treated as being equivalent to the distortion in the signal domain. To reduce the error caused by direct distortion evaluation in the wavelet domain, the weighting factors are applied to the used statistical distortion model in the second strategy. In the last strategy, the derived statistical model is used during the bit-plane encoding to determine optimal position of the fractional bit-plane corresponding to refinement information in the compressed bit-stream. Results of selected experiments measuring peak signal to noise ratio (PSNR) of decoded video at various bit-rates are reported.

关键词： bit-plane coding embedded coding fractional bit-plane ordering low bit-rate coding post-compression rate-distortion optimization scalable video coding

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A framework for efficient progressive fine granularity scalable video coding

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IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY 2001年第3期11卷 332-344页

作者： Wu, F Li, SP Zhang, YQ Microsoft Res China Beijing 100080 Peoples R China

In this paper, a basic framework for efficient scalable video coding, namely progressive fine granularity scalable (PFGS) video coding is proposed. Similar to the fine granularity scalable (FGS) video coding in MPEG-4, the PFGS framework has all the features of FGS, such as fine granularity bit-rate scalability, channel adaptation, and error recovery. On the other hand, different from the FGS coding, the PEGS framework uses multiple layers of references with increasing quality to make motion prediction more accurate for improved video-coding efficiency. However, using multiple layers of references with different quality also introduces several issues. First, extra frame buffers are needed for storing the multiple reconstructed reference layers. This would increase the memory cost and computational complexity of the PEGS scheme. Based on the basic framework, a simplified and efficient PEGS framework is further proposed. The simplified PFGS framework needs only one extra frame buffer with almost the same coding efficiency as in the original framework. Second, there might be undesirable increase and fluctuation of the coefficients to be coded when switching from a low-quality reference to a high-quality one, which could partially offset the advantage of using a high-quality reference. A further improved PFGS scheme can eliminate the fluctuation of enhancement-layer coefficients when snitching references by always using only one high-quality prediction reference for all enhancement layers. Experimental results show that the PFGS framework can improve the coding efficiency up to more than 1 dB over the FGS scheme in terms of average PSNR, yet still keeps all the original properties, such as fine granularity, bandwidth adaptation, and error recovery. A simple simulation of transmitting the PFGS video over a wireless channel further confirms the error robustness of the PEGS scheme, although the advantages of PFGS have not been fully exploited.

关键词： bandwidth adaptation bit-plane coding error recovery fine granularity scalability layer-based video coding

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An efficient hardware implementation of parallel EBCOT algorithm for JPEG 2000

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JOURNAL OF REAL-TIME IMAGE PROCESSING 2016年第1期11卷 63-74页

作者： Saidani, Taoufik Atri, Mohamed Khriji, Lazhar Tourki, Rached Monastir Univ Fac Sci Elect & Microelect Lab Monastir Tunisia Sultan Qaboos Univ Dept Elect & Comp Engn Muscat Oman

With the augmentation in multimedia technology, demand for high-speed real-time image compression systems has also increased. JPEG 2000 still image compression standard is developed to accommodate such application requirements. Embedded block coding with optimal truncation (EBCOT) is an essential and computationally very demanding part of the compression process of JPEG 2000 image compression standard. Various applications, such as satellite imagery, medical imaging, digital cinema, and others, require high speed and performance EBCOT architecture. In JPEG 2000 standard, the context formation block of EBCOT tier-1 contains high complexity computation and also becomes the bottleneck in this system. In this paper, we propose a fast and efficient VLSI hardware architecture design of context formation for EBCOT tier-1. A high-speed parallel bit-plane coding (BPC) hardware architecture for the EBCOT module in JPEG 2000 is proposed and implemented. Experimental results show that our design outperforms well-known techniques with respect to the processing time. It can reach 70 % reduction when compared to bit plane sequential processing.

关键词： JPEG 2000 EBCOT algorithm bit-plane coding VHDL FPGA implementation

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High compression and low order linear predictor for lossless coding of grayscale images

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IMAGE AND VISION COMPUTING 2003年第6期21卷 543-550页

作者： Baligar, VP Patnaik, LM Nagabhushana, GR Indian Inst Sci Dept High Voltage Engn Bangalore 12 Karnataka India Indian Inst Sci Dept Comp Sci & Automat Microproc Applicat Lab Bangalore 12 Karnataka India

In this paper we propose a novel method for designing block-wise lossless image compression scheme using linear predictors. In this prediction scheme, the prediction for each pixel is formed by using a set of least-square-based linear prediction coefficients of the block to which the current pixel belongs. Predicted value of each pixel is subtracted from the actual value of the current pixel to get an error image. An error image is compressed using grayscale bit plane coding using quadtree method. Experimental results show that the compression performance of the proposed method is superior to Joint Photographics Expert Group's [1] JPEG-LS [IEEE Trans. Image Processing 9 (2000) 1309] method, and Classified Adaptive Prediction and Entropy coding in terms of coding performance. (C) 2003 Elsevier Science B.V. All rights reserved.

关键词： image compression bit-plane coding quadtree decomposition linear prediction

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Video Compression by bit-plane Watermarking

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INTERNATIONAL JOURNAL OF IMAGING SYSTEMS AND TECHNOLOGY 2008年第4期18卷 257-264页

作者： Wang, Chuen-Ching Chen, Bo-Yu Natl Changhua Univ Educ Dept Elect Engn Changhua 500 Taiwan

This article proposes a new fragile watermarking scheme named bit-plane watermarking (BPW) which considers ways to improve coding efficiency whereas providing watermarking capability. Because of the use of the run-length coding strategy for embedding watermark information, the BPW not only verifies the authenticity and integrity of video streams, but also can recompress the bit streams for improving the compression ratio. To verify the effectiveness of this new concept, we select the MPEG-4 FGS as the platform for implementation. The watermark is embedded in the bit-plane blocks of MPEG-4 FGS enhancement layer bitstream, and the coefficient in each bit-plane block is automatically selected so that the run-length symbols can be reduced and the location of embedded bits is not required to memorize. The effectiveness of the proposed scheme is demonstrated in a series of experimental simulations. It is shown that the scheme successfully detects changes made to the content of MPEG-4 FGS video streams and identifies the specific location at which these changes have been made. Furthermore, the results show that the scheme can further reduce the length of compressed bit stream. (C) 2008 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 18, 257-264, 2008;Published online in Wiley InterScience (***). DOI 10.1002/ima.20134

关键词： MPEG-4 bit-plane coding FGS video authentication digital watermarking video surveillance

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Successive refinement for the Wyner-Ziv problem and layered code design

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IEEE TRANSACTIONS ON SIGNAL PROCESSING 2005年第8期53卷 3269-3281页

作者： Cheng, S Xiong, ZX Texas A&M Univ Dept Elect Engn College Stn TX 77843 USA

We examine successive refinement for the Wyner-Ziv problem described in a recent paper by Steinberg and Merhav, where the authors showed that if the side information for all stages is identical, then the jointly Gaussian source with squared error distortion measure is successively refinable. We first extend this result to the case where the difference between the source and the side information is Gaussian and independent of the side information. As a byproduct, we give an alternative proof that the Wyner-Ziv problem for these sources has no rate loss-a result that was recently shown by Pradhan et al. through invoking the duality between the Gaussian Wyner-Ziv problem and the Costa problem. We then perform layered Wyner-Ziv code design for this general type of source based on nested scalar quantization, bit-plane coding, and low-density parity check (LDPC) code-based Slepian-Wolf coding (source coding with side information). We show that density evolution can be used to analyze the Slepian-Wolf code performance, provided that certain symmetry conditions, which have been dubbed dual symmetry, are satisfied by the hypothetical channel between the source and the side information. We also show that the dual symmetry condition is indeed satisfied by the hypothetical channel in our Slepian-Wolf coding setup. This justifies the use of density evolution in our LDPC code-based Slepian-Wolf code design for Wyner-Ziv coding. For the jointly Gaussian source, our layered coder performs 1.29 to 3.45 dB from the Wyner-Ziv bound for rates ranging from 0.47 to 4.68 bits per sample. When the side information is Laplacian and the source equals the side information plus an independent Gaussian noise term, our layered coder performs 1.33 to 3.90 dB from the Wyner-Ziv bound for rates ranging from 0.48 to 4.64 bits per sample.

关键词： bit-plane coding LDPC coding nested scalar quantization Slepian-Wolf coding successive refinement Wyner-Ziv coding

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