Efficient scheme for motion estimation and block size mode selection in H.264

The paper presents efficient algorithms for enhancing the computational performance of an H.264 video encoder. We employ previously calculated motion vectors and variable block size modes from neighboring blocks to select the best modes and motion vectors for the current macroblock. The scheme results in 40% to 70% improvement in the encoding time over a reference implementation without degradation in the subjective quality. The average SNR and the compression performance do not show variation from the reference codec implementation. Results based on a number of video sequences are presented that clearly demonstrate the benefit of the proposed motion estimation and block size mode selection algorithm. The proposed scheme has been shown to provide the least computational load with improvement in the encoding time. The reduction in memory requirements and calculations makes this scheme useful for VLSI implementation and realtime applications.