An H.264 Spatial-temporal Hierarchical Fast Motion Estimation Algorithm for High-Definition VideoAbstract H.264 advanced
video coding exhibits much higher coding gain as well as computational
complexity than previous video coding standards due to the utilization of
coding tools such as variable block size and multi-reference frame in motion
compensation process. There exist plenty of research outcomes that focus on
the development of H.264 fast algorithms. The limited bandwidth during the access between
hardware components and the external memory often becomes the bottleneck of
the system performance. One of the solutions of encoding the high-definition
video in hardware with limited resources is to employ a hierarchical subsampling structure with the parallel-processing
hardware architecture. The main objective of this work is to maintain both
the video quality and bit-rate while pursuing the gain from computational
complexity reduction. This thesis proposes a hierarchical H.264 fast
motion estimation algorithm by decreasing the coding complexity in both
spatial and temporal domains. In spatial domain, we utilize the hierarchical
search method to decrease the search points. In temporal domain, we utilize
the linear motion model to reduce the search range. The simulation results
show that the proposed algorithm can reduce the computational complexity to
as low as 1.80% compared to JM12.4 with less than 0.10dB video quality
degradation. |