Title :
Parallel rate-distortion optimized intra mode decision on multi-core graphics processors using greedy-based encoding orders
Author :
Cheung, Ngai-Man ; Au, Oscar C. ; Kung, Man-Cheung ; Fan, Xiaopeng
Author_Institution :
Dept. of Electron. & Comput. Eng., Hong Kong Univ. of Sci. & Technol., Hong Kong, China
Abstract :
Rate-distortion (RD) optimized intra-prediction mode selection can lead to significant improvement in coding efficiency in intra-frame encoding. However, it would incur considerable increase in encoding complexity. In this paper, we investigate how multi-core Graphics Processing Units (GPUs) can be efficiently utilized to undertake the task of RD optimized intra mode selection in AVS and H.264 video encoding. Achieving efficient GPU-based intra mode decision, however, could be non-trivial. It is because the mode decision of the current block would depend on the reconstructed data of the neighboring blocks. Therefore, the coding modes of neighboring blocks would need to be computed first before that of the current block can be determined. This dependency poses challenge to computation on multi-core GPUs, which rely heavily on parallel data processing to achieve superior speedups. To address this issue, we analyze the data dependency in intra mode decision, and propose novel greedy-based encoding orders to achieve highly parallel processing. We also prove that the proposed greedy-based orders are optimal in terms of execution time. Experimental results suggest that the proposed GPU-based intra mode decision compares favorably to the counterpart implemented on a single-core CPU.
Keywords :
computational complexity; coprocessors; greedy algorithms; parallel processing; video coding; AVS video encoding; H.264 video encoding; data dependency; encoding complexity; greedy-based encoding orders; intra mode decision; intra-frame encoding; multicore graphics processors; parallel data processing; parallel rate-distortion optimization; Acceleration; Central Processing Unit; Computer graphics; Concurrent computing; Cost function; Encoding; Parallel processing; Quantization; Rate-distortion; Video compression; GPU; RD optimized intra-prediction; greedy approach; multi-core; parallel processing;
Conference_Titel :
Image Processing (ICIP), 2009 16th IEEE International Conference on
Conference_Location :
Cairo
Print_ISBN :
978-1-4244-5653-6
Electronic_ISBN :
1522-4880
DOI :
10.1109/ICIP.2009.5414475