Adaptive FMO strategy for video transcoding

An adapt flexible macroblock ordering strategy based on unequal protection scheme is presented for video transcoding. The key point of our scheme is selecting the important macroblocks which belong to a separate slice group under prior protection in transmission. The judgement of the importance of the macroblocks is based on the differences of the DCT coefficients of neighbouring subblocks in a macroblock which represent the texture change and the complexity of the macroblock content. The number of the important macroblocks can be controlled effectively in predetermined range. The other macroblocks judged as unimportant are classified into two slices according to the edge match rule contributing to the efficiency of the error concealment in decoder. The adapt FMO scheme enhance error resilient capability and improve error concealment capability in decoder. Experiments shows that the proposed flexible macroblock ordering strategy improve the subjective quality and objective quality 2-3 dB than traditional FMO type such as interlaced type and dispersed type suggested by h.264 if one unimportant slice is corrupted.