An efficient scalable multi-granularity HEVC encoder based on embedded system

As the latest video coding standard, HEVC dramatically reduced the bit-rate compared with H.264/AVC. However, the complexity has strongly increased. In order to accelerate the video coding, it is a trend in recent years that video coding is implemented in parallel based on the multi-core processors, especially in the embedded system. In this paper, a scalable multi-granularity encoder is proposed for the embedded system. In the encoder, firstly, the parallel granularities in HEVC are analyzed, and the tiles, CTUs(Code Tree Units) and pixels are mapped reasonably to the processors, cores and the computing units to fully utilize the advantages of them. Secondly, the data exchange and synchronization messages in the parallel granularities are analyzed, and are to be efficiently dispatched to the local/shared memory or the high-speed communication interfaces to increase the process of the encoding. Therefore, the video encoding is processed efficiently. The experiment shows that the speedup is about 10.8 on the 14 cores on average and it is an approximately linearity with the processors. The videos that resolution is equal to or lower than 720P can be encoded in real-time on the hardware platform composed with two TMS320C6678s.