Efficient and low cost video transcoding

We present a low cost high performance scheme for video transcoding. Our scheme includes the information look-ahead structure and the transcoding algorithm. It is this look-ahead mechanism that greatly facilitates the use of information embedded in the bitstream for informative and intelligent transcoding. Furthermore, our transcoding algorithm has four new features: 1) picture complexity look-ahead for efficient rate allocation and control; 2) dynamic bit allocation weighting on picture types based on the scene complexity and bit rate; 3) adaptive nonlinear rate control on macroblocks based on complexity distribution in the picture; 4) Intra frame requantization adjustment to reduce the transcoding distortion. The software simulation results have proven that the performance of our transcoding scheme is significantly better than the reencoding scheme and comparable to the direct encoding scheme.