Complexity scalable inter modes decision algorithm for H.264 based on spatial correlation

In this paper, the complexity scalability for H.264 motion estimation was explored. The algorithm proposed uses a probability table to relate the prediction modes of adjacent MBs to that of the current MB. For each combination of adjacent MBs, the probability table includes a list of prediction modes in order of expected occurrence. Hence the number of modes used can be adjusted under different complexity constraints while the optimum mode is guaranteed to lie in the chosen modes with great possibility. The experimental results show that the proposed method can save the encoding time effectively and flexibly with acceptable performance degradation.