<title>A novel multiple description scalable coding scheme for mobile wireless video transmission</title>

Abstract

We proposed in this paper a new multiple description scalable coding (MDSC) scheme based on in-band motion compensation temporal filtering (IBMCTF) technique in order to achieve high video coding performance and robust video transmission. The input video sequence is first split into equal-sized groups of frames (GOF). Within a GOF, each frame is hierarchically decomposed by discrete wavelet transform. Since there is a direct relationship between wavelet coefficients and what they represent in the image content after wavelet decomposition, we are able to reorganize the spatial orientation trees to generate multiple bit-streams. We have shown that multiple bit-stream transmission is very effective in combating error propagation in both Internet video streaming and mobile wireless video. We adopt the IBMCTF in our MDSC scheme to take full advantage of its good performance with flexible scalability, particularly at low spatial resolution. To achieve high coding performance for each bit-stream, we apply in-band motion estimation and motion compensated temporal filtering using over-complete DWT of each frame. Furthermore, we adopt bi-directional motion estimation between different bit-streams so as to facilitate the error concealment at the decoder to guarantee robust video transmission over error prone channels. Unlike traditional multiple description schemes, the integration of these techniques enable us to generate more than two bit-streams that may be more appropriate for multiple antenna transmission of compressed video. The integration also provides flexible tradeoff between coding efficiency and error resilience. Preliminary results on several standard video sequences have confirmed the high coding performance and flexible scalability.