Complexity Control Strategy for Real-Time H.264/AVC Encoder

The H.264/AVC encoder acquires high coding efficiency by using the various coding techniques, but requires very high computational complexity. Therefore, H.264/AVC encoder causes the problem of preserving acceptable video coding performance in the low-power/processor environments, such as wireless mobile. To optimize the rate-distortion (R-D) and complexity, we analyze the encoding structure and establish an analytic model for complexity. From this analysis, we propose a new approach for real-time encoder which maintains both frame rate and video quality. An encoding time control algorithm investigates the results of P16x16 motion estimation (ME) in the current frame and decides the number of skipped macroblocks (MBs) in order to encode the frame within the allocated target encoding time. A complexity control algorithm manages the coding complexity of each frame by preventing motion estimations for smaller modes. Simulation results show that compared to the existing algorithm, the proposed algorithm can maintain frame rate without significant degradation of visual quality and increase in bit rate.