Mapping of H.264/AVC Encoder on a Hierarchical Chip Multicore DSP Platform

The emergence of large-scale chip multicore processors makes the on-chip parallel H.264/AVC encoder with high parallelism feasible. To reduce the data reload frequency, a hierarchical chip multi-core DSP platform with overall 64 DSP cores is designed to accommodate the computation/data-intensive H.264/AVC encoder. To increase parallelism, macro block level parallelism is exploited in this paper and wave front algorithm is utilized. Centralized shared memory in super nodes of this hierarchical DSP platform affords larger local space to hold the frequently used data and reduce bandwidth requirement. Subtask level parallelism within motion estimation, intra prediction and mode decision is further exploited to keep the DSP cores in a super node busy even only one macro block are assigned to a super node. Because of lack of available macro blocks in filling and emptying stages when encoding a frame, super nodes cannot be kept busy all the time and speedups of 13, 24, 26 and 49 are achieved for QCIF, SIF, CIF and HD sequences, respectively. To further improve the speedups and make best use of the processor resources, frame level parallelism should be exploited with carefully tuned memory allocation policy.