Lucas Lopes, Philip A. Chou, Ricardo L. de Queiroz · 2022
<p>Arithmetic coding is used in most media compression methods. Context modeling is usually done through frequency counting and look-up tables (LUTs). For long-memory signals, probability modeling with large context sizes is often infeasible. Recently, neural networks have been used to model probabilities of large contexts in order to drive arithmetic coders. These neural networks have been trained offline. We introduce an online method for training a perceptron-based context-adaptive arithmetic coder on-the-fly, called adaptive perceptron coding, which continuously learns the context probabilities and quickly converges to the signal statistics.We test adaptive perceptron coding over a binary image database, with results always exceeding the performance of LUT-based methods for large context sizes and of recurrent neural networks. We also compare the method to a version requiring offline training, which leads to equally satisfactory results.</p>
Cited by 0Open access
Ben Hamida Asma, Nedra Jarray, Abdelkrim Zitouni · Greater South Information System · 2017
Context-Based Adaptive Binary Arithmetic Coding (CABAC) is a well-known bottleneck in H.264/AVC, owing to the highly serialized calculation and high data dependency of the binary arithmetic encoder.This work presents a hardware architecture for the sub-module binary arithmetic encoder of the CABAC.Moreover, a clock gating technique is inserted into our design for power saving.An FPGA design of the proposed architecture can work at a frequency up to 268 MHz on Virtex 5.The suggested design can achieve 17% of power consumption saving, which allows it to be applied for low power video coding applications.
Cited by 0Open access
2006
Context-based adaptive binary arithmetic coding (CABAC) is the major entropy-coding algorithm employed in H.264/AVC. Although the performance gain of H.264/AVC is mainly due to CABAC, it is difficult to achieve a fast decoder because the decoding algorithm is basically sequential and computationally intensive. In this letter, a prediction scheme is proposed that enhances overall decoding performance by decoding two binary symbols at a time. A CABAC decoder based on the proposed prediction scheme improves the decoding performance by 24% compared to conventional decoders. Key words: video coding, arithmetic codes, prediction theory, entropy codes
Cited by 0
Tung Nguyen, Detlev Marpe, Heiko Schwarz et al. · 2011
In hybrid video coding, the difference between the intra or inter prediction signal and the original signal is transmitted using block-based transform coding. The state-of-the-art in coding the quantized transform coefficients is the approach specified in H.264/AVC for context-adaptive binary arithmetic coding. It has, however, been shown that the number of binary symbols that have to be arithmetically coded for the transform coefficients can become very large, making the concept less attractive for high rate applications. To overcome this issue, we propose a combination of simple variable-length codes and context-adaptive binary coding, which yields the same coding efficiency as the H.264/AVC transform coefficient coding at a lower complexity level and which has been adopted into the HEVC test model (HM).
Cited by 16
Mo Li, Wuchen Wu · 2006
Context-based adaptive binary arithmetic coding (CABAC) adopted by the latest video coding standard- H.264/AVC main profile, can achieve good compression performance both in encoding and decoding H.264 syntax element. However, the binary coding engine of CABAC is bitwise in H.264/AVC, which leads to the limited throughput of CABAC encoder. Also the traditional iterative scheme for renormalization in binary arithmetic coding can result in degradation of coding efficiency. To avoid more costly operation in CABAC, an efficient coding design for handling high-resolution video sequence is strongly required. This paper proposes an optimized parallel processing approach and high throughput architecture design for renormalization in binary arithmetic coding engine, which is well suited for efficient software and hardware implementation over H.264/AVC HDTV encoder. Comparing with the traditional design, the results show that this novel approach makes a symbol encoded in one cycle; and for a set of test sequences, the throughput rate has been increased nearly 20% on average
Cited by 2
Detlev Marpe, Heiko Schwarz, Thomas Wieg · 2011
In hybrid video coding, the difference between the intra or inter prediction signal and the original signal is transmitted using block-based transform coding. The state-of-the-art in coding the quantized transform coefficients is the approach specified in H.264/AVC for context-adaptive binary arithmetic coding. It has, however, been shown that the number of binary symbols that have to be arithmetically coded for the transform coefficients can become very large, making the concept less attractive for high rate applications. To overcome this issue, we propose a combination of simple variable-length codes and context-adaptive binary coding, which yields the same coding efficiency as the H.264/AVC transform coefficient coding at a lower complexity level and which has been adopted into the HEVC test model (HM). Index Terms — Transform coding, video compression 1.
Cited by 0
Wei Yu, Ping Yang, Yun He · 2008
Abstract: arithmetic coding (AC) is notable for its high compression gain and high implementation cost. The coding process includes range update, renormalization, and probability estimation update. Old AC engine realized both range update and probability estimation update by multiplications or table look-up. In this paper, we replace multiples with additions by combining original domain and logarithmic domain. We kept the cost of alternation between two domains low by employing approximation and optional modification. Moreover, renormalization takes place only when least probable symbol happens so that much time can be saved for renormalization process. Overall coding speed and implementation cost is improved compared to old AC engine. Context Adaptive Binary Arithmetic Coding (CABAC) [1] was one of the two alternative entropy coding method specified in H.264. Compared to the other technique Context Adaptive Variable Length Coding (CAVLC), CABAC entails an access frequency increase from 25 % to 30 % with bit rate reduction up to 16 % [2]. The original principle of the binary arithmetic coding is based on recursive interval subdivision of the interval width R [3]. Given the estimation of the probability p of least probable symbol (LPS), the LPS
Cited by 0
Damian Karwowski, Marek Domański · 2007
In this paper, an improvement of coding efficiency of the Context-based Adaptive Binary Arithmetic Coding (CABAC) is proposed for applications in Advanced Video Codecs (H.264/AVC). In the paper, more accurate estimation technique for conditional probabilities of symbols is proposed. To achieve that, the well-known data modeling technique of the Context-Tree Weighting (CTW) is used. A novel method of incorporating CTW into the H.264/AVC codec is proposed. The compression efficiency of the modified H.264/AVC codec (with CTW) has been thoroughly tested and compared against the coding efficiency of the original H.264/AVC (with CABAC). Experimental results show that the use of CTW with CABAC allows for up to 2.5 % compression efficiency increase with respect to the original CABAC. Index Terms — Adaptive arithmetic coding, context-tree weighting, entropy coding, hybrid compression
Cited by 0
Xiao Huo, Shidi Hao, Wei Zhang et al. · APSIPA Transactions on Signal and Information Processing · 2025
The Moving Picture Experts Group (MPEG) has published the geometry-based point cloud compression (G-PCC) standard. It converts the compression of irregular point coordinates to the coding of structured binary octree node occupancy, where the Context-based Adaptive Binary Arithmetic Coding (CABAC) can be applied. The context model, constructed by intra and inter-octree layer information, drives the probability update of the arithmetic coder with a so-called Optimal Binarization with Update On-the-Fly (OBUF) scheme. The original OBUF design, while effective, lacks a probability range limitation for each binary coder, leading to issues in probability estimation accuracy and convergence speed. Moreover, when coding dynamic point clouds, the inter-frame information is not efficiently considered in OBUF, leading to excessive memory consumption for storing and tracking context states. To address these challenges, we propose an initialization strategy for both fine-grained context states (Fine-CtxS) and coarse-grained context states (Coarse-CtxS) in OBUF, alongside an adaptive probability bound determination method for each Coarse-CtxS to confine probability estimation. Furthermore, the paper delves into improvements for inter-frame geometry coding, including the construction of Fine-CtxS, and reducing memory consumption of Fine-CtxS in OBUF. The proposed methods have been adopted in recent G-PCC Edition 2 standardization activities, demonstrating enhanced performance.
Cited by 0Open access
Alexander Alshin, Elena Alshina, JeongHoon Park · 2013
Entropy coding is the main important part of all advanced video compression schemes. Context-adaptive binary arithmetic coding (CABAC) is entropy coding used in H.264/MPEG-4 AVC and H.265/HEVC standards. Probability estimation is the key factor of CABAC performance efficiency. In this paper high accuracy probability estimation for CABAC is presented. This technique is based on multiple estimations using different models. Proposed method was efficiently realized in integer arithmetic. High precision probability estimation for CABAC provides up-to 1,4% BD-rate gain.
Cited by 23
Hyunmin Jung, Soonwoo Choi, Soo‐Ik Chae · 2015
This paper evaluates the coding efficiency of the HM 13.0 HEVC rate-distortion optimizing (RDO) encoder before and after the context-adaptive binary arithmetic coding (CABAC) engine is replaced with the context-based arithmetic coding (CBAC) engine of AVS 2.0. In addition, the rate errors are controlled by varying the bit length of the fractional part for the estimated bit in the rate estimation table. The experimental result shows that the CBAC engine provides 0.21% BD-rate reduction on average, compared to the CABAC engine in the HEVC Test Model (HM) 13.0 encoder, when the bit length of the fractional part of the estimated rate is 3.
Cited by 2
Zhenyu Liu, Sanchuan Guo, Dongsheng Wang · 2014
Rate-Distortion Optimization in High Efficiency Video Coding promotes the coding efficiency, but also imposes intensive computation to the encoder, because the complex Syntax-based context-adaptive Binary Arithmetic Coding is performed for each candidate coding configuration. We develop the classification based regression method to derive the rate models, which fast estimate the bit cost of quantization coefficient block from its distribution features. Experiments demonstrate that, our method reduces the averaged 28.4% computation time in rate cost estimation, while the coding efficiency degradation is 0.0428dB.
Cited by 11
Damian Karwowski, Marek Domański · International Journal of Electronics and Telecommunications · 2018
The paper presents Improved Adaptive Arithmetic Coding algorithm for application in future video compression technology. The proposed solution is based on the Context-based Adaptive Binary Arithmetic Coding (CABAC) technique and uses the authors mechanism of symbols probability estimation that exploits Context-Tree Weighting (CTW) technique. This paper proposes the version of the algorithm, that allows an arbitrary selection of depth D of context trees, when activating the algorithm in the framework of the AVC or HEVC video encoders. The algorithm has been tested in terms of coding efficiency of data and its computational complexity. Results showed, that depending on depth of context trees from 0.1% to 0.86% reduction of bitrate is achieved, when using the algorithm in the HEVC video encoder and 0.4% to 2.3% compression gain in the case of the AVC. The new solution increases complexity of entropy encoder itself, however, this does not cause an increase of the complexity of the whole video encoder.
Cited by 5Open access
Madhu Krishnan, Liang Zhao, Zhipeng Dong et al. · 2025
Entropy coding is an integral part of all modern hybrid block-based video codecs. The context adaptive binary arithmetic coding (CABAC) is a normative part of ITU-T/ISO/IEC video coding standards (H.264/AVC, HEVC and VVC), while the Alliance for Open Media (AOMedia) video standard (AV1) utilizes a context adaptive multi-symbol version of it for entropy coding. Recent explorations of new coding tools beyond AV1 capabilities have led to the improvement of the context adaptive multi-symbol arithmetic entropy coder. In this study, improvements to the context initialization process of the entropy coder are discussed in detail and results reported. The improvements include a) optimal selection of reference frame pairs and b) context modeling from selected reference frame pairs for tile context initialization. Two variants of the proposed method, Variant1 and Variant2 are implemented on top of the reference codebase (research-v8.0.0). Experimental results with CTCv7 show that for random access (RA) configuration, average BDRATE (PSNR-YUV) gains of -0.13% and -0.18% are achievable for Variant1 and Variant2 respectively. Meanwhile, for low delay (LD) configuration the reported gains are -0.47% and -0.50% respectively for Variant1 and Variant2.
Cited by 2
Alonso Aymone de Almeida Schmidt · 2011
This work presents the integration of CABAD (Context-based Adaptive Binary Arithmetic Decoder) into the H.264/AVC hardware video decoder for the Brazilian Digital Television System (SBTVD). In the hardware architecture, CABAD is a sub-module of the parser. The latter is responsible for controlling the flow of the syntactic elements that must be decoded to supply parameters needed by the other video decoder modules in order to reconstruct the images. Those modules are the MC (Motion Compensation), the Intra (spatial prediction), the IQIT (Inverse Quantization and Inverse Transform) among others. CABAC (Context-based Adaptive Binary Arithmetic Coding) compress data by combining binary arithmetic coding with context modeling based on syntactic elements values nearby that were previously decoded and on local statistics, thus optimizing probability estimation. The algorithm of CABAD comprehends essentially the processes of context selection, binary arithmetic decoding and de-binarization. The target-module for integration requires a vector of input signals to accomplish the processes of the algorithm and external control for its initialization, enabling and for retrieving decoded values. Those requisites promotes the development of a bit-stream handler, a syntactic elements manager, a residual coefficients block builder and a synchronizing control. After integration of the developed modules, the parser’s operation is verified with a bit-stream of video generated by a reference software encoder, comparing expected values with signals obtained through simulation. FPGA synthesis of the parser after the integration of CABAD reaches maximum frequency of 56 MHz, and at 50 MHz it is verified that the data throughput is sufficient to process HD 720p video.
Cited by 0
C.-H. KIM, In‐Cheol Park · IEICE Transactions on Information and Systems · 2007
Context-based adaptive binary arithmetic coding (CABAC) is the major entropy-coding algorithm employed in H.264/AVC. Although the performance gain of H.264/AVC is mainly due to CABAC, it is difficult to achieve a fast decoder because the decoding algorithm is basically sequential and computationally intensive. In this letter, a prediction scheme is proposed that enhances overall decoding performance by decoding two binary symbols at a time. A CABAC decoder based on the proposed prediction scheme improves the decoding performance by 24% compared to conventional decoders.
Cited by 9
BAO Xian-yu1, JIANG Jian-guo1.2, YUAN Wei1 et al. · SHILAP Revista de lepidopterología · 2007
Several candidate domains were analyzed and summarized to apply encryption to the latest video coding standard H.264/AVC,and a novel digital video encryption scheme based on CABAC（context-based adaptive binary arithmetic coding） was proposed.During the CABAC encoding,two kinds of secure encryption operations including RCME（regular coding mode encryption） and BCME（bypass coding mode encryption） were utilized,in order to encrypt residual coefficient codeword,motion vector difference codeword and intra-prediction mode,respectively.The experimental results show that the scheme has significant advantages on security,coding efficiency,and errors robustness.
Cited by 0Open access
Bin Guo, Weidong Wang, Shen Yu-li et al. · 2007
Context Adaptive Binary Arithmetic Coding (CABAC) is a highly efficient entropy coding way, but its coding speed is restricted by high computational complexity, which becomes a major bottleneck in its application. Based on the analysis of the CABAC algorithm and its computational complexity, by improving the probability estimation update part, an effective way to improve its coding speed will be proposed in this paper. The experimental results show that the coding speed of CABAC has been substantially raised meanwhile coding efficiency decline a little.
Cited by 2
Chengiie Tu, Jie Bang, Trac D. Tran · Proceedings - International Conference on Image Processing · 2003
Runlength coding is the standard coding technique for block transform based image/video compression. A block of quantized transform coefficients is first represented as a sequence of RUN (number of consecutive zeros) / LEVEL (the value of the following nonzero coefficient) pairs which are then entropy coded. We point out in this paper the inefficiency of conventional runlength coding and introduce a novel adaptive runlength coding scheme that encodes RUN and LEVEL symbols separately using context based adaptive binary arithmetic coding. We aim to maximize compression efficiency by adaptively exploiting the characteristics of block transform coefficients and the dependency between RUN and LEVEL. Coding results show that, with the same level of complexity, the proposed adaptive runlength coding algorithm outperforms the conventional runlength coding scheme by a wide margin in the rate-distortion (R-D) sense.
Cited by 5
Van Truong Nguyen, А А Тропченко · SPIIRAS Proceedings · 2018
Modern video coding standards have high coding efficiency, but the encoding performance has to be improved to meet the growing multimedia applications. The paper deals with the entropy encoding methods and algorithms in video coding standard H.264/AVC and H.265/HEVC. Context-based Adaptive Variable Length Coding (CAVLC) for the H.264/AVC standard was originally designed for lossy video coding, and as such does not yield adequate performance for lossless video coding. Context-Adaptive Binary Arithmetic Coding (CABAC) is a method of entropy coding first introduced in H.264/AVC and now used in the standard H.265/HEVC. While it provides high coding efficiency, the data dependencies in H.264/AVC CABAC make it challenging to parallelize and thus, limit its throughput. Accordingly, during the standardization of entropy coding for HEVC, both coding efficiency and throughput were considered. Based on an analysis of their advantages and disadvantages, a method called the entropy coding algorithm using the enumerative coding of the hierarchical approach is proposed. The proposed algorithm consists of the Context-Adaptive Binary Arithmetic Coding algorithm and the enumerative coding algorithm with a hierarchical approach. The proposed algorithm is tested in the Visual C ++ development environment on various test video sequences. The results of the experiments showed a greater efficiency of coding of multimedia data (the proposed one reduces on average up to 15% of the storage volume compared to the traditional CABAC method), while the method requires a longer coding time (approximately twice). The proposed method can be recommended for use in telecommunication systems for storage, transmission and processing of multimedia data, where a high degree of compression is required first.
Cited by 0Open access