Early Termination and Pipelining for Hardware Implementation of Fast H.264 Intraprediction Targeting Mobile HD Applications
- 444 Downloads
H.264/AVC adopts aggressive compression algorithms at the cost of increased computational complexity. To speed up the H.264/AVC intraframe coding, this paper proposes two novel techniques: early termination and pipelined execution. In P slices, intra 4×4 and 16×16 predictions are early terminated with the threshold determined by the cost of motion estimation. In I slices, intra 4×4 prediction is early terminated with the threshold derived from intra 16×16 prediction. The threshold function is chosen as a monotonically decreasing linear function with its optimal coefficients determined by experiments. For the pipelined execution of 4×4 intrapredictions, the processing order of 4×4 blocks is changed to reduce the dependencies between consecutively processed blocks. In I slices, computation for 4×4 intraprediction is reduced by 19 percent with the proposed early termination. In P slices, computations for 4×4 and 16×16 intrapredictions are reduced by more than 81 and 91 percents, respectively. The pipelined execution reduces the computation time by 41 percent. In spite of the speed-up by the proposed methods, degradation in rate-distortion performance is negligible. The proposed pipelined execution is integrated with other H.264/AVC hardware accelerators and fabricated as an SoC using Dongbu 0.13 μm technology.
KeywordsInformation Technology Linear Function Computation Time Computational Complexity Early Termination
To access the full article, please see PDF.
This article is published under license to BioMed Central Ltd. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.