Flexible and Efficient Switching Techniques between Scalable Video Bitstreams

In this paper, we first describe a seamless switching scheme for scalable video bitstreams that fully takes advantage of both the high coding efficiency of non-scalable bitstreams and the flexibility of scalable bitstreams. Small bandwidth fluctuations are absorbed by the scalability of the bitstreams, while large bandwidth fluctuations are tolerated by switching between scalable bitstreams. Flexible and efficient switching techniques are investigated as the focus of this paper. A flexible method is proposed to switch from current scalable bitstream to one operated at lower rates at any frame without any overhead bits. Since additional bits are necessary in the proposed scheme when switching from a scalable bitstream operated at lower rates to one operated at higher rates, an efficient method is proposed to greatly reduce the amount of overhead bits. Experimental results show that the seamless switching scheme with the proposed switching techniques significantly outperforms both the approach with a single scalable bitstream and the approach of switching among multiple nonscalable bitstreams.