Video transcoding technology in IPTV applications
Rong Ding · Journal of Tsinghua University(Science and Technology) · 2006
An IPTV(internet protocol TV) application scheme was developed to broadcast DVBS(digital video broadcasting-satellite) video live to users with different internet bandwidths.Motion re-estimation was used to transcode MPEG(moving picture experts group)-2 video to lower bitrate MPEG-4 video real time to avoid bandwidth limits.The motion re-estimation algorithm builds an inverse MV(motion vector) lookup table using the overlap area to speed up the MV search and estimates the MV based on the neighbor macroblock's MV.The algorithm efficiently improves the transcoding while maintaining video quality.Simulations show that the video transcoding process uses 40% less encoding time than the PMVfast(predictive motion vector field adaptive search technique) algorithm with the PSNR(peak signal-to-noise ratio) reduced by less than(0.3 dB.)