Tuyển tập các báo cáo nghiên cứu về hóa học được đăng trên tạp chí hóa hoc quốc tế đề tài : Efficient bitstream switching for streaming of coded video | Altaf et al. EURASIP Journal on Image and Video Processing 2011 2011 7 http content 2011 1 7 D EURASIP Journal on Image and Video Processing a SpringerOpen Journal RESEARCH Open Access Efficient bitstream switching for streaming of AVC coded video Muhammad Altaf1 Ekram Khan2 Mohammad Ghanbari3 and Nadia N Qadri4 Abstract In this article a novel scheme is proposed for switching among multiple bitrate video streams over Internet to achieve best quality of service QoS . The research is focused on selecting the best switching points inside the precoded variable bit rate video streams to facilitate bandwidth scalability among the non-scalable multiple bitstreams. With a stepwise monotonically decreasing downstairs bandwidth reservation scheme it is shown that if switching occurs at the transition points in the downstairs then the best QoS can be achieved. However insertion of switching pictures at these transition points may change the characteristics of the downstairs function and hence the bandwidth requirement. Here we propose a scheme for proper management of the allocated resources to facilitate the stream switching in the downstairs through SP-frames. The performance is measured in terms of the wastage of bits in the receiver buffer and bandwidth utilization at the switching instances. Keywords bitstream switching downstairs reservation scheme AVC QoS SP-frames video streaming 1. Introduction In video streaming applications such as video-on-demand archived video news and non-interactive distance learning video sequences are generally encoded offline and stored in a server 1 . To receive and play the stored video at any time users may access the server over a shared channel such as the Internet. For continuous display of variable bit rate VBR -coded video over such a time varying network a part of the video bitstream needs to be pre-loaded in the receiver buffer to ensure that every frame is decoded at its scheduled time. One of
