Arbitrary frame rate transcoding through temporal and spatial complexity

In this paper, an arbitrary frame rate transcoding joint considering temporal and spatial complexity of frames in the adaptive length sliding window is proposed. The length of a sliding window can be adjusted according to bandwidth variation in order to decide the number of skipped frames. The proposed method preserves significant frames and drops non-significant ones using the complexity measurements. Moreover, the motion vector composition algorithm is proposed to reduce the computations of motion estimation process by adopting the coding feature of variable block sizes in H.264/AVC video transcoder. Experimental results show that the proposed method achieves higher visual quality compared to other existing methods. After combining with the proposed fast motion composition algorithm, our proposed algorithm reduces encoding time significantly with slight visual quality degradation.