Compressed-domain motion detection for efficient and error-resilient MPEG-2 to H.264 transcoding

In this paper, a novel compressed-domain motion detection technique, operating on MPEG-2-encoded video, is combined with H.264 flexible macroblock ordering (FMO) to achieve efficient, error-resilient MPEG-2 to H.264 transcoding. The proposed motion detection technique first extracts the motion information from the MPEG-2-encoded bit-stream. Starting from this information, moving regions are detected using a region growing approach. The macroblocks in these moving regions are subsequently encoded separately from those in background regions using FMO. This can be used to increase error resilience and/or to realize additional bit-rate savings compared to traditional transcoding.