The goal of this paper is to improve human visual perceptual quality as well as coding efficiency of H. 264 video at low bit rate conditions by adaptively adjusting the number of skipped frames. The encoding frames ar...The goal of this paper is to improve human visual perceptual quality as well as coding efficiency of H. 264 video at low bit rate conditions by adaptively adjusting the number of skipped frames. The encoding frames are selected according to the motion activity of each frame and the motion accumulation of successive frames. The motion activity analysis is based on the statistics of motion vectors and with consider- ation of the characteristics of H. 264 coding standard. A prediction model of motion accumulation is pro- posed to reduce complex computation of motion estimation. The dynamic encoding frame rate control algorithm is applied to both the frame level and the GOB （Group of Macroblocks ） level. Simulation is done to compare the performance of JM76 with the proposed frame level scheme and GOB level scheme.展开更多
Intra-frame plays a significant role in improving video quality for rate control of H.264/AVC.In this paper,an efficient intra-frame rate control algorithm is proposed for H.264/AVC video coding.The proposed scheme ad...Intra-frame plays a significant role in improving video quality for rate control of H.264/AVC.In this paper,an efficient intra-frame rate control algorithm is proposed for H.264/AVC video coding.The proposed scheme adjusts the quantization parameter （QP） of intra-frame adaptively according to intra-frame buffer fullness ratio,current buffer fullness ratio,and skipped frame ratio.Experimental results demonstrate that for a set of typical testing sequences,the proposed scheme can obtain accurate target bit rate,better peak signal-to-noise ratio （PSNR） performance and reduce the number of skipped frames significantly,when compared with existing schemes.More importantly,the proposed scheme is very flexible for different initial QPs and target bits.展开更多
Current multi-view video coding （MVC） reference model in joint video team （JVT） does not provide efficient rate control schemes. This paper presents a rate control algorithm for MVC by improving the quadratic rate...Current multi-view video coding （MVC） reference model in joint video team （JVT） does not provide efficient rate control schemes. This paper presents a rate control algorithm for MVC by improving the quadratic rate-distortion （R-D） model. We reasonably allocate bit-rate among views based on the correlation analysisl The proposed algorithm consists of three levels to control the rate bits more accurately, of which the frame layer allocates bits according to the frame complexity and the temporal activity. Extensive experiments show that the proposed algorithm can control the bit rate efficiently.展开更多
Hierarchical B-frames can bring high coding performance when introduced into H.264/AVC.However,the traditional rate control schemes can not work efficiently in such new coding framework.This article presents a rate co...Hierarchical B-frames can bring high coding performance when introduced into H.264/AVC.However,the traditional rate control schemes can not work efficiently in such new coding framework.This article presents a rate control algorithm for hierarchical B-frames in H.264/AVC.Taking the feature of the dyadic hierarchical coding structure into consideration,the proposed algorithm includes group of pictures （GOP） layer,temporal layer and frame layer bits allocation.After frame layer bits allocation is complete,frame layer quantization parameters （QP） determination strategy is responsible for calculating the final QP.Experimental results show that compared with other rate control algorithms,the proposed one can improve the coding performance and reduce the mismatch of target bit rate and real bit rate.展开更多
分析通用数据传输服务质量(quality of service,QoS)技术,探讨实时传输及实时传输控制协议(real-time transport protocol/real-time transport control protocol,RTP/RTCP)、H.264数据预测编码等相关技术在无线传输过程中的作用,提出...分析通用数据传输服务质量(quality of service,QoS)技术,探讨实时传输及实时传输控制协议(real-time transport protocol/real-time transport control protocol,RTP/RTCP)、H.264数据预测编码等相关技术在无线传输过程中的作用,提出一种智能丢包和速率控制的联合策略。在分析视频数据帧结构相似特性的基础上,建立数据差错传输模型,引入一种数据帧重要性评估方案,通过对发送数据包的标记,利用RTCP反馈机制,在不同的带宽和缓冲区阈值实现动态智能丢包或改变速率。将其应用于自主研发的多平台无线投影装置,测试结果表明,添加QoS保障后,无线投影仪具有实时、高清的效果,该联合信道和缓冲区的QoS控制策略是有效的。展开更多
基金Supported by the High Technology. Research and Development Program of China （No. 2005AA103310） and the National Natural Science Foundation of China （No. 60202006）.
文摘The goal of this paper is to improve human visual perceptual quality as well as coding efficiency of H. 264 video at low bit rate conditions by adaptively adjusting the number of skipped frames. The encoding frames are selected according to the motion activity of each frame and the motion accumulation of successive frames. The motion activity analysis is based on the statistics of motion vectors and with consider- ation of the characteristics of H. 264 coding standard. A prediction model of motion accumulation is pro- posed to reduce complex computation of motion estimation. The dynamic encoding frame rate control algorithm is applied to both the frame level and the GOB （Group of Macroblocks ） level. Simulation is done to compare the performance of JM76 with the proposed frame level scheme and GOB level scheme.
基金Supported by the National Science Foundation for Creative Research Groups of China (60821062)
文摘Intra-frame plays a significant role in improving video quality for rate control of H.264/AVC.In this paper,an efficient intra-frame rate control algorithm is proposed for H.264/AVC video coding.The proposed scheme adjusts the quantization parameter （QP） of intra-frame adaptively according to intra-frame buffer fullness ratio,current buffer fullness ratio,and skipped frame ratio.Experimental results demonstrate that for a set of typical testing sequences,the proposed scheme can obtain accurate target bit rate,better peak signal-to-noise ratio （PSNR） performance and reduce the number of skipped frames significantly,when compared with existing schemes.More importantly,the proposed scheme is very flexible for different initial QPs and target bits.
基金supported by the National Natural Science Foundation of China (Grant Nos.60832003,60672052,60902085,60972137)the Key Project of Shanghai Municipal Education Commission (Grant No.09ZZ90)+2 种基金the Natural Science Foundation of Shanghai(Grant No.09ZR1412500)the Innovation Foundation of Shanghai University (Grants Nos.10YZ09,SHUCX091061)the Shuguang Plan of Shanghai Education Development Foundation (Grant No.06SG43)
文摘Current multi-view video coding （MVC） reference model in joint video team （JVT） does not provide efficient rate control schemes. This paper presents a rate control algorithm for MVC by improving the quadratic rate-distortion （R-D） model. We reasonably allocate bit-rate among views based on the correlation analysisl The proposed algorithm consists of three levels to control the rate bits more accurately, of which the frame layer allocates bits according to the frame complexity and the temporal activity. Extensive experiments show that the proposed algorithm can control the bit rate efficiently.
基金supported by the National Natural Science Foundation of China (60672087)
文摘Hierarchical B-frames can bring high coding performance when introduced into H.264/AVC.However,the traditional rate control schemes can not work efficiently in such new coding framework.This article presents a rate control algorithm for hierarchical B-frames in H.264/AVC.Taking the feature of the dyadic hierarchical coding structure into consideration,the proposed algorithm includes group of pictures （GOP） layer,temporal layer and frame layer bits allocation.After frame layer bits allocation is complete,frame layer quantization parameters （QP） determination strategy is responsible for calculating the final QP.Experimental results show that compared with other rate control algorithms,the proposed one can improve the coding performance and reduce the mismatch of target bit rate and real bit rate.
文摘分析通用数据传输服务质量(quality of service,QoS)技术,探讨实时传输及实时传输控制协议(real-time transport protocol/real-time transport control protocol,RTP/RTCP)、H.264数据预测编码等相关技术在无线传输过程中的作用,提出一种智能丢包和速率控制的联合策略。在分析视频数据帧结构相似特性的基础上,建立数据差错传输模型,引入一种数据帧重要性评估方案,通过对发送数据包的标记,利用RTCP反馈机制,在不同的带宽和缓冲区阈值实现动态智能丢包或改变速率。将其应用于自主研发的多平台无线投影装置,测试结果表明,添加QoS保障后,无线投影仪具有实时、高清的效果,该联合信道和缓冲区的QoS控制策略是有效的。
