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A perceptual rate control algorithm based on luminance adaptation for HEVC encoders

SIGNAL IMAGE AND VIDEO PROCESSING 2020年第5期14卷 887-895页

作者： Lim, Woong Sim, Donggyu Kwangwoon Univ Dept Comp Engn 20 Gwangun Ro Seoul South Korea

This paper proposes a rate control algorithm by selecting a proper quantization parameter (QP) based on perceptual luminance adaptation in a single-loop encoding fashion. In this paper, the proposed algorithm uses the visual characteristics of humans to adaptively decide the number of bits available for a pixel. Then, a base QP is selected based on the proposed R-lambda model. The proposed rate control determines the range of QP based on the base QP and calculates the maximum and minimum bpps within that range. The optimal bpp is obtained from the bpp range by considering the visual characteristics of the human being, and the QP value is determined by the optical bpp through the proposed R-lambda model. In the proposed rate control algorithm, the QP value is selected based on the R-lambda model by considering the perceptual luminance adaptation model at the CTU level. The number of target bits is decided to decide the QP, subject to visual sensitivity based on JND thresholds. With the use of the proposed rate control algorithm, bits for non-noticeable regions can be saved, and the remaining bits can be consumed for perceptually noticeable regions to enhance the overall subjective quality with the similar amount of total bits. The proposed method shows lower average variances of bits and PSNR fluctuations. Also, the proposed method achieves an approximately 0.19 higher MOS value on average under DSCQS test, compared with the conventional R-lambda model-based rate control algorithm.

关键词： HEVC Perceptual coding rate control algorithm R-lambda model JND luminance adaptation

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Adaptive and efficient rate control algorithm with different routing protocols in VANET

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Applied Mathematics and Information Sciences 2018年第4期12卷 877-883页

作者： Karthik Kumar, P. Krishnaveni, V. Department of Information and Communication Engineering Anna University Chennai India Department of Electronics and Communication Engineering PSG College of Technology Coimbatore India

The objective of the work is to find the best combination of rate control algorithm with routing protocol and implement them to improve the performance of the Vehicular Ad Hoc Network (VANET). In this paper, the performance of rate control algorithm with different routing protocols is evaluated for the real-time scenario in vehicular networks. Real-time map and the traffic are generated using Simulation of Urban Mobility (SUMO). control algorithms and routing protocols are taken into consideration and simulated using Network Simulator version 3 (NS3). Goodput, Packet delivery ratio and routing overhead are parameters used for the analysis. The simulation results in low densities of vehicles show thatMinstrel rate control algorithm with DSDV routing protocol performs best, whereas in high densities of vehicles AARF algorithm with DSDV routing protocol performs best in terms of average goodput when compared with other approaches. © 2018 NSP.

关键词： rate control algorithm Routing protocol SUMO VANET

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rate control algorithm Considering Mobility in Mobile Ad Hoc Networks

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INTERNATIONAL JOURNAL OF WIRELESS INFORMATION NETWORKS 2010年第1-2期17卷 26-33页

作者： Zhou, Xian-Wei Miao, Xu-Na Wang, An-Ping He, Biao Zhou, Jian Univ Sci & Technol Beijing Sch Informat Engn Dept Commun Engn Beijing 100083 Peoples R China Univ Sci & Technol Beijing Sch Informat Engn Dept Commun Engn Dept Commun Sci & Engn Beijing 100083 Peoples R China

For reducing the loss of data packet due to network congestion and mobility, rate control algorithm is effective means for ensuring the fair allocation of network resource among communication flows and alleviating network congestion. The Transport control Protocol (TCP) was originally designed for wire-line networks, where the links are assumed to be reliable and with fixed capacities. However, the performance of TCP becomes very poor when it is directly used in ad hoc networks. Some optimization-based congestion control schemes have been proposed to improve TCP performance in ad hoc networks, but the mobility of hosts and route change frequently are not considered for designing rate control algorithm. In this paper, we propose rate control algorithms in a more practical way by taking into account link congestion and node movement. Numerical results show that the rate control algorithms can approach the globally optimal value and show the effect of the node mobility on the algorithms.

关键词： Ad hoc networks rate control algorithm Node mobility Network congestion

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Attentional mechanisms driven adaptive quantization and selective bit allocation scheme for H.264/AVC

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SIGNAL PROCESSING-IMAGE COMMUNICATION 2013年第8期28卷 843-855页

作者： Hrarti, Miryem Saadane, Abdelhakim Larabi, Mohamed-Chaker Barland, Remi Univ Poitiers XLIM SIC Poitiers France Univ Mohammed V Agdal GSCM LRIT Unite Associee CNRST URAC 29 Rabat Morocco Univ Nantes F-44035 Nantes France

rate control algorithm adopted in H.264/AVC reference software shows several shortcomings that have been highlighted by different studies. For instance, in the baseline profile, the frame target bit-rate estimation assumes similar characteristics for all frames and the quantization parameter determination uses the Mean Absolute Difference for complexity estimation. Consequently, an inefficient bit allocation is performed leading to important quality variation of decoded sequences. A saliency-based rate-control is proposed in this paper to achieve bit-rate saving and improve perceived quality. The saliency map of each frame, simulating the human visual attention by a bottom-up approach, is used at the frame level to adjust the quantization parameter and at the macroblock level to guide the bit allocation process. Simulation results show that the proposed attentional model is well correlated to human behavior. When compared to JM15.0 reference software, at the frame level, the saliency map exploitation achieves bit-rate savings of up to 26%. At the MB level and under the same quality constraint, bit-rate improvement is up to 42% and buffer level variation is reduced by up to 71%. (C) 2013 Elsevier B.V. All rights reserved.

关键词： H.264/AVC Saliency map rate control algorithm Bit allocation Quantization parameter

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A Perceptual Optimization of H.264/AVC Bit Allocation at the Frame and Macroblock Levels

A Perceptual Optimization of H.264/AVC Bit Allocation at the...

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Conference on Image Quality and System Performance IX

作者： Hrarti, M. Saadane, H. Larabi, M. -C. Tamtaoui, A. Aboutajdine, D. Univ Poitiers XLim Inst SIC Lab Marie & Pierre Currie BvdBP 30179-86962 Futurosc Poitiers France Univ MohamedV Fac Sci GSCM LRIT Lab Unit Attached CNRST Rabat Morocco Nantes Univ Polytech Sch Nantes France Natl Inst Post & Telecommun LTI Lab Rabat Morocco

ISBN: (纸本)9780819489401

In H.264/AVC rate control algorithm, the bit allocation process and the QP determination are not optimal. At frame layer, there is an implicit assumption considering that the video sequence is more or less stationary and consequently the neighbouring frames have similar characteristics. So, the target Bit-rate for each frame is estimated using a straightforward process that allocates an equal bit budget for each frame regardless of its temporal and spatial complexities. This uniform allocation is surely not suited especially for all types of video sequences. The target bits determination at macroblock layer uses the MAD (Mean Absolute Difference) ratio as a complexity measure in order to promote interesting macroblocks, but this measure remains inefficient in handling macroblock characteristics. In a previous work we have proposed rate-Quantization (R-Q) models for Intra and Inter frames used to deal with the QP determination shortcoming. In this paper, we look to overcome the limitation of the bit allocation process at the frame and the macroblock layers. At the frame level, we enhance the bit allocation process by exploiting frame complexity measures. Thereby, the target bit determination for P-frames is adjusted by combining two temporal measures: The first one is a motion ratio determined from actual bits used to encode previous frames. The second measure exploits both the difference between two consecutive frames and the histogram of this difference. At macroblock level, the visual saliency is used in the bit allocation process. The basic idea is to promote salient macroblocks. Hence, a saliency map, based on a Bottom-Up approach, is generated and a macroblock classification is performed. This classification is then used to accurately adjust UBits(H264) which represents the usual bit budget estimated by H.264/AVC bit allocation process. For salient macroblocks the adjustment leads to a bit budget which is always larger than UBits(H264). The extra bits added to

关键词： H.264/AVC Standard Complexity measure rate-Quantization model Inter/Intra Frame rate control algorithm Quantization Parameter Bit Allocation Saliency MAP

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Improving the quality of H. 264/AVC by using a new rate-Quantization model

Improving the quality of H. 264/AVC by using a new Rate-Quan...

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Conference on the Image Quality and System Performance VIII

作者： Hrarti, M. Saadane, H. Larabi, M-C. Tamtaoui, A. Aboutajdine, D. Univ Poitiers SIC Lab XLim Inst Marie & Pierre Currie BvdBP 30179-86962 Futurosc Poitiers France Univ MohamedV Fac Sci GSCM LRIT Lab Rabat Morocco Nantes Univ Polytech Sch Nantes France Natl Inst Post & Telecommun LTI Lab Rabat Morocco

ISBN: (纸本)9780819484048

rate control plays a key role in video coding standards. Its goal is to achieve a good quality at a given target bit-rate. In H.264/AVC, rate control algorithm for both Intra and Inter-frames suffers from some defects. In the Intra-frame rate control, the initial quantization parameter (QP) is mainly adjusted according to a global target bit-rate and length of GOP. This determination is inappropriate and generates errors in the whole of video sequence. For Inter coding unit (Frame or Macroblock), the use of MAD (Mean Average Differences) as a complexity measure, remains inefficient, resulting in improper QP values because the MAD handles locally images characteristics. QP miscalculations may also result from the linear prediction model which assumes similar complexity from coding unit to another. To overcome these defects, we propose in this paper, a new rate-Quantization (R-Q) model resulting from extensive experiments. This latter is divided into two models. The first one is an Intra R-Q model used to determine an optimal initial quantization parameter for Intra-frames. The second one is an Inter R-Q model that aims at determining the QP of Inter coding unit according to the statistics of the previous coded ones. It does not use any complexity measure and substitutes both linear and quadratic models used in H.264/AVC rate controller. Objective and subjective simulations have been carried out using JM15.0 reference software. Compared to this latter, the global R-Q model (Intra and Inter models combined) improves the coding efficiency in terms of PSNR, objectively (up to +2.01dB), subjectively (by psychophysical experiments) and in terms of computational complexity.

关键词： H.264/AVC Standard Complexity measure rate-Quantization model Inter/ Intra Frame rate control algorithm

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Block based Method for Real-Time Compound Video Compression

Block based Method for Real-Time Compound Video Compression

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Conference on Mobile Multimedia/Image Processing, Security, and Applications 2010

作者： Han, Bing Wu, Dapeng Zhang, Huipin Univ Florida Dept Elect & Comp Engn Gainesville FL 32611 USA Cisco Syst Santa Clara CA 95054 USA

ISBN: (纸本)9780819481726

In this paper, we propose a novel compound video compression method for real-time applications of computer screen video transmission. The compound video is a very special kind of video, which usually has less motion and contains a mixture of text, graphics, and natural pictures in each frame. A variety of algorithms has been proposed for compound image compression, which tries to remove the spatial redundancy of a single image. However, few works have addressed the problem of compound videos compression. Therefore, we review the previous works on compound image compression and discuss how to extend the existing algorithms to compound video compression. We propose a new video compression framework based on H.264. In order to improve the visual performance and network efficiency, we propose an adaptive quantization algorithm and a rate control algorithm for compound video compression. The experimental results show that the new compression method is able to compress the compound video in real-time with a relatively low computational complexity and with the motion compensation, the visual quality of the compound video is much better than simple compound image compression.

关键词： Compound video compression real-time transmission adaptive quantization rate control algorithm

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AN INNOVATIVE APPROACH FOR ADAPTATION OF GENERIC rate control algorithmS FOR TARGET VIDEO STANDARDS

AN INNOVATIVE APPROACH FOR ADAPTATION OF GENERIC RATE CONTRO...

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IEEE International Conference on Signal Processing and Communications

作者： Agarwal, Megha Johar, Sumit Saha, Kaushik Piccinelli, Emiliano STMicroelect Pvt Ltd Adv Syst Technol Gnoida 201308 UP India STMicroelect Adv Syst Technol I-20041 Agrate Brianza MI Italy

ISBN: (纸本)9781424412358

This paper discusses an innovative approach to make a generic rate control algorithm adaptable to a specific targeted video standard, by incorporating the 'Adaptation layer'. The proposed Adaptation Layer utilizes the technique of statistical regression to provide a mechanism using which the rate control algorithm can be acclimatized to any video standard. Experimental results, on applying the proposed technique on a constant bitrate control algorithm for VC1 show that a maximum deviation of 1.5% from the target bitrate is obtained with desired quality. Furthermore, the proposed technique drastically reduces the design complexity required in adapting a rate control algorithm to a particular video standard with a marginal increase in computational complexity.

关键词： Video Coding rate control algorithm Adaptation Layer Quantization parameter

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rate-constrained arbitrarily shaped video object coding with object-based rate control

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IEE PROCEEDINGS-VISION IMAGE AND SIGNAL PROCESSING 2004年第4期151卷 250-256页

作者： Chen, Z Ngan, KN Chinese Univ Hong Kong Dept Elect Engn Shatin Hong Kong Peoples R China

The authors develop an object-based rate control algorithm for MPEG-4 arbitrarily shaped video object coding. There are three main contributions. An improved quadratic rate-distortion model for texture information is derived, which is more accurate for arbitrarily shaped video objects. Secondly, an accurate rate-distortion model for shape information is introduced. Combining the rate-distortion models for texture and shape information, an object level rate control is proposed. To achieve constant bit rate, the quantiser is adjusted based on buffer fullness. The tradeoff between picture quality and buffer fullness is considered. Compared with the rate control algorithm for the MPEG-4 verification model, the proposed scheme can achieve a more stable buffer without sacrificing picture quality.

关键词： .texture information shape information rate control algorithm picture quality texture and shape ratedistortion shaped video objects rate-distortion models buffer fullness stable buffer

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A region-based H.263+codec and its rate control for low VBR video

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IEEE TRANSACTIONS ON MULTIMEDIA 2004年第3期6卷 489-500页

作者： Song, HJ Kuo, CCJ Hongik Univ Sch Elect Engn Seoul South Korea Univ So Calif Integrated Multimedia Syst Ctr Los Angeles CA 90089 USA Univ So Calif Dept Elect Engn Syst Los Angeles CA 90089 USA

This paper presents a region-based video codee, which is compatible with the H.263+ standard, and its associated rate control algorithm for low variable-bit-rate (VBR) video. The proposed region-based coding scheme is a hybrid method that incorporates traditional block DCT coding as well as object-based coding. To achieve this, we adopt H.263+ as the platform, and develop a fast macroblock-based segmentation method to implement the new region-based codec. The associated rate control solution includes rate control in three levels: encoding frame selection, frame-layer rate control and macroblock-layer rate control. The goal is to improve human visual perceptual quality at low bit rates. The efficiency of the proposed rate control algorithm applied to the region-based H.263+ codec is demonstrated via several typical test sequences.

关键词： .coding scheme rate control algorithm frame-layer Low VBR Region-Based Codec region-based video encoding frame

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