Optimal Mode Decision Method for Interframe Prediction in H.264/AVC

Studies show that encoding technologies in H.264/AVC,including prediction and conversion,are essential technologies.However,these technologies are more complicated than the MPEG-4,which is a standard method and widely adopted worldwide.Therefore,the amount of calculation in H.264/AVC is significantly up-regulated compared to that of the MPEG-4.In the present study,it is intended to simplify the computational expenses in the international standard compression coding system H.264/AVC for moving images.Inter prediction refers to the most feasible compression technology,taking up to 60%of the entire encoding.In this regard,prediction error and motion vector information are proposed to simplify the computation of inter predictive coding technology.In the initial frame,motion compensation is performed in all target modes and then basic information is collected and analyzed.After the initial frame,motion compensation is performed only in the middle 8×8 modes,and the basic information amount shifts.In order to evaluate the effectiveness of the proposed method and assess the motion image compression coding,four types of motion images,defined by the international telecommunication union(ITU),are employed.Based on the obtained results,it is concluded that the developed method is capable of simplifying the calculation,while it is slightly affected by the inferior image quality and the amount of information.

Efficient fast mode decision using mode complexity for multi-view video coding

The variable block-size motion estimation(ME) and disparity estimation(DE) are adopted in multi-view video coding(MVC) to achieve high coding efficiency. However, much higher computational complexity is also introduced in coding system, which hinders practical application of MVC. An efficient fast mode decision method using mode complexity is proposed to reduce the computational complexity. In the proposed method, mode complexity is firstly computed by using the spatial, temporal and inter-view correlation between the current macroblock(MB) and its neighboring MBs. Based on the observation that direct mode is highly possible to be the optimal mode, mode complexity is always checked in advance whether it is below a predefined threshold for providing an efficient early termination opportunity. If this early termination condition is not met, three mode types for the MBs are classified according to the value of mode complexity, i.e., simple mode, medium mode and complex mode, to speed up the encoding process by reducing the number of the variable block modes required to be checked. Furthermore, for simple and medium mode region, the rate distortion(RD) cost of mode 16×16 in the temporal prediction direction is compared with that of the disparity prediction direction, to determine in advance whether the optimal prediction direction is in the temporal prediction direction or not, for skipping unnecessary disparity estimation. Experimental results show that the proposed method is able to significantly reduce the computational load by 78.79% and the total bit rate by 0.07% on average, while only incurring a negligible loss of PSNR(about 0.04 d B on average), compared with the full mode decision(FMD) in the reference software of MVC.

Adaptive early termination of fast mode decision in MVC based on inter-view correlation

Variable size motion estimation （ME） and disparity estimation （DE） are employed to select the best coding mode for each macroblock （MB） in the current joint multiview video model （JMVM）. This technique achieves the highest possible coding efficiency, but it results in extremely large computation complexity which obstructs the multiview video coding （MVC） from practical application. This paper proposes an adaptive early termination of fast mode decision algorithm for MVC. It makes use of the coding information of the corresponding MBs in neighbor view based on inter-view correlation to early terminate the mode decision procedure. Experimental results show that the proposed fast mode decision algorithm can achieve computational 50% computation saving with no significant loss of rate distortion （RD） performance.

Fast mode decision for inter macroblocks in H. 264/AVC

In this paper, a fast mode decision algorithm for inter macroblocks in H.264/AVC is proposed, The algorithm is able to classify all modes by both gradient operator and comparison of space-time correlation. Because only part of modes is used to compare with each other the computational complexity can be reduced greatly. The simulation results show that it takes about 75 % of encoding time for other algorithm with similar visual quality.

Edge Feature Based Fast Mode Decision Algorithm for H.264 Intra Prediction

A fast intra mode decision algorithm is proposed in this paper to reduce the complexity of H. 264 encoder. The proposed algorithm adopted the pre-processing method based on edge feature in pictures to filter out some impossible prediction modes. Context information and pre-computed threshold are used to determine whether it is necessary to check the DC mode. This method is able to get rid of most of candidate modes so that only 66--150 modes are left for the final mode decision, instead of 592 modes in the case of full search （FS） method of H. 264. Simulation results demonstrate that the coding time of the proposed algorithm falls down 71.7% compared with FS method, while the performance loss is trivial compared with FS mode decision scheme.

Fast inter-mode decision method based on best matching block for H.264 encoding

In H.264 encoder, all possible coding modes should be checked to choose the most appropriate mode for every macroblock, which adds a heavy computation burden to the encoder. In this paper, a fast inter-mode decision method is presented to reduce computation complexity of an H.264 encoder. By detecting the best matching block （BMB） before transform and quantization, some coding modes can be skipped and the corresponding encoding steps can be omitted for these BMBs. Meanwhile this method can also be used to detect all-zero blocks. The experimental results show that this method achieves consistently significant reduction of encoding time while keeping almost the same rate-distortion performance.

Fast mode decision for Hierarchical-B pictures in scalable video coding

To decrease the computational complexity of adaptive inter-layer prediction and improve the encoding efficiency in sealable video coding, a mode decision algorithm is proposed by exploiting the part of used candidate modes of the co-located reference macrobloeks for Hierarchical-B pictures. This scheme reduces the amount of the candidate modes to generate a dynamic list for the current encoding macroblock according to the statistical information derived from the co-located reference macroblocks in different temporal levels. The experimental results show that this fast algorithm reduces approximately 31% encoding time on average with the negligible loss of encoding performance.

Mode decision for H.264 down-scaling video transcoding

Although the coding modes of H.264 coded video would be changed by the transcoding process of spatial resolution reduction, there exists good correlation in prediction modes and prediction directions between input and output video. In this paper, we first introduce a new spatial resolution reduction transcoding architecture of intra coded frames where the distortion can be calculated directly in compression domain. We then propose a fast mode decision algorithm in which only a small part of rate distortion optimization （RDO） calculation is needed for mode decision. For 4×4 luma block, the proposed scheme has average 21.3% computation saving, compared to the cascaded pixel-domain transcoding scheme with the fast intra mode decision algorithm proposed in JVT-G013. For 16×16 luma block, RDO calculation is completely avoided in our scheme while the scheme in JVT-G013 needs 2 RDO calculations. Experimental results show that our scheme outperforms that of JVT-G013 in terms of significantly computasavings with negligible loss of PSNR

Portable Perceptron Network-Based Fast Mode Decision for Video-Based Point Cloud Compression

In Video-based Point Cloud Compression(V-PCC),2D videos to be encoded are generated by 3D point cloud projection,and compressed by High Efficiency Video Coding(HEVC).In the process of 2D video compression,the best mode of Coding Unit(CU)is searched by brute-force strategy,which greatly increases the complexity of the encoding process.To address this issue,we first propose a simple and effective Portable Perceptron Network(PPN)-based fast mode decision method for V-PCC under Random Access(RA)configuration.Second,we extract seven simple hand-extracted features for input into the PPN network.Third,we design an adaptive loss function,which can calculate the loss by allocating different weights according to different Rate-Distortion(RD)costs,to train our PPN network.Finally,experimental results show that the proposed method can save encoding complexity of 43.13%with almost no encoding efficiency loss under RA configuration,which is superior to the state-of-the-art methods.The source code is available at https://github.com/Mesks/PPNforV-PCC.

Dominant edge direction based fast intra mode decision in the H.264/AVC encoder

The H.264/AVC video coding standard uses an intra prediction mode with 4×4 and 16×16 blocks for luma and 8×8 blocks for chroma. This standard uses the rate distortion optimization (RDO) method to determine the best coding mode based on the compression performance and video quality. This method offers a large improvement in coding efficiency compared to other compression standards, but the computational complexity is greater due to the various intra prediction modes. This paper proposes a fast intra mode decision algorithm for real-time encoding of H.264/AVC based on the dominant edge direction (DED). The DED is extracted using pixel value summation and subtraction in the horizontal and vertical directions. By using the DED, three modes instead of nine are chosen for RDO calculation to decide on the best mode in the 4×4 luma block. For the 16×16 luma and the 8×8 chroma, only two modes are chosen instead of four. Experimental results show that the entire encoding time saving of the proposed algorithm is about 67% compared to the full intra search method with negligible loss of quality.

H.264/SVC Mode Decision Based on Mode Correlation and Desired Mode List

Design of video encoders involves implementation of fast mode decision(FMD) algorithm to reduce computation complexity while maintaining the performance of the coding. Although H.264/scalable video coding(SVC) achieves high scalability and coding efficiency, it also has high complexity in implementing its exhaustive computation. In this paper, a novel algorithm is proposed to reduce the redundant candidate modes by making use of the correlation among layers. A desired mode list is created based on the probability to be the best mode for each block in base layer and a candidate mode selection in the enhancement layer by the correlations of modes among reference frame and current frame. Our algorithm is implemented in joint scalable video model(JSVM)9.19.15 reference software and the performance is evaluated based on the average encoding time, peak signal to noise ration(PSNR)and bit rate. The experimental results show 41.89% improvement in encoding time with minimal loss of 0.02 dB in PSNR and 0.05%increase in bit rate.

Fast Inter Coding Mode Selection Algorithm for H.264

In order to reduce the encoding complexity of macroblock coding mode decision in H.264/AVC, a selective smaller block-size searching algorithm and a selective intra coding mode searching algorithm are proposed by using the high correlation among coding modes and in spatial and temporal domains of video sequence. Simulation results demonstrate that the proposed algorithm can provide significant improvement in computational requirement, with negligible small picture quality degradation and slight bit rate increase.

调节模式与决策角色对延迟选择的影响及机制:过程追踪的视角

从过程追踪视角出发,运用信息板技术通过3个实验探讨调节模式对延迟选择的影响及信息加工方式(加工时间、加工深度、加工模式)与决策角色在其中的中介和调节作用。结果发现:(1)调节模式影响个体的延迟选择,评估比运动模式者更倾向于延迟选择;(2)加工时间在调节模式与延迟选择间起中介作用;(3)决策角色分别调节了调节模式与加工时间、延迟选择的关系,即为自我决策时,评估模式比运动模式者的加工时间更长、更倾向于延迟选择,而为他人决策时二者的偏好无显著差异;(4)决策角色调节了加工时间在调节模式与延迟选择中的中介作用,表现为有调节的中介,即为自我决策时,评估模式比运动模式者的加工时间更长致使其更倾向延迟选择,而为他人决策时加工时间的中介作用不显著。研究结果对进一步理解不同调节模式个体的延迟选择偏好及机制及如何根据不同调节模式消费者的差异制定有效的营销策略均有一定启示。

Efficient video downscaling transcoder from MPEG-2 to H.264

The new H.264 video coding standard achieves significantly higher compression performance than MPEG-2. As the MPEG-2 is popular in digital TV, DVD, etc., bandwidth or memory space can be saved by transcoding those streams into H.264 in these applications. Unfortunately, the huge complexity keeps transcoding from being widely used in practical applications. This paper proposes an efficient transcoding architecture with a smart downscaling decoder and a fast mode decision algorithm. Using the proposed architecture, huge buffering memory space is saved and the transcoding complexity is reduced. Performance of the proposed fast mode decision algorithm is validated by experiments.

建构自主开放的语文教育学教学模式

课题组从培养适应素质教育和基础教育课程改革需要的新型师资出发,以语文教育学课程新目标的建构为切入点,以具有示范、中介、启发功能的范例体系建设和指向课程新目标的作业体系建设为关键,以新的平时测评、模拟教学、期末卷面考试相结合的结构性教学评价方式为保障机制,设计并实践了“开放性自主式教学模式”,从根本上改变了师传生受,以见习、实习为点缀的传统教学模式,已取得明显成效。

The evolution of investments decision mode in China's telecommunication

This essay analyzes the data of Chinese telecommunication market, telecommunication investments and investment benefits over the past 20 years. On the basis of these data, the essay reviews Chinese changing telecommunication policies and discusses the major events in the course of China＇s telecommunication development. It is argued that telecommunication policies, regime backgrounds and market demand characteristics have a significant impact on investment decision mode in telecommunication industry. The evolution of network investments decision mode in China＇s telecommunication has corresponded to the transformation of these key factors. Considering the special events in the development of Chinese telecommunication as divisions, the essay discusses three stages of the evolution of investments decision mode in China＇s tel With the firm environment and problems that Chinese telecommunication operators have been facing since 2000 analyzed, it is demonstrated that Chinese telecommunication operators should change their mode of investment decision into the ＂profit-oriented investment decision mode＂ in order to achieve a high growth performance in the capital market,. This investment decision mode will result in increase of the investment profit with limited investment capital. The main procedure of profit-oriented investment decision mode is set out, which is abstracted to a mathematical model eventually.

Considering the cost-effectiveness of statins in family practice in Turkey from a payer perspective

The percentage of mortality caused by cardio-vascular events in European Countries and European Union Countries is respectively 49% and 42% of all mortality causes. Our estimates about cardiovascular mortality in Turkey depend on TEKHARF (Hearth Disease and Risk Factors in Turkish Adults) which depended on a 12 year observation. It has been reported that cardio-vascular mortality rates for Turkey in men and women were 0.082% and 0.043% respectively. In Turkey, Atorvastatin, Fluvastatin, Pravastatin, Rosuvastatin and Simvastatin are the different alternatives found in the statin market. All stat-ins are reimbursed by insurance companies. The aim of this study is to determine the cost- effectiveness of statins. In conclusion, simvas-tatin and rosuvastatin comprised the optimal two statin alternatives.

Approach for earth observation satellite real-time and playback data transmission scheduling

The scheduling of earth observation satellites(EOSs)data transmission is a complex combinatorial optimization problem. Current researches mainly deal with this problem on the assumption that the data transmission mode is fixed, either playback or real-time transmission. Considering the characteristic of the problem, a multi-satellite real-time and playback data transmission scheduling model is established and a novel algorithm based on quantum discrete particle swarm optimization(QDPSO)is proposed. Furthermore, we design the longest compatible transmission chain mutation operator to enhance the performance of the algorithm. Finally, some experiments are implemented to validate correctness and practicability of the proposed algorithm.