On improving the robustness of compressed video by Slepian-Wolf based lossless transcoding
A variety of techniques have been proposed to enhance the error robustness of the video streaming system. However, most of them improve the error resilience during compression rather than after compression. In this paper, we propose a novel transcoding based scheme called Slepian-Wolf based inter frame transcoding (SWIFT) to improve the error resilience of existing compressed video stream. In the SWIFT scheme, inter coded blocks are selectively transcoded into new kind of blocks called ‘X-block’. At the decoder, the X-block can be transcoded back to the original P-block when there is no error in the prediction, and can also be robustly decoded as I-block when there are errors in the prediction. In the experiments, the proposed SWIFT scheme does not introduce transcoding distortion as expected, and always improves the robustness of the compressed video at all packet loss rate. Compared with the H.264 based transcoder, SWIFT achieves better RD performance and error resilience performance.