DescriptionThis poster describes a heterogeneous HEVC video encoder system based on the OpenPOWER platform. Our design leverages the Coherent Accelerator Processor Interface (CAPI) on the OpenPOWER, which provides cache-coherent access for FPGA. This technology highly improves CPU-FPGA data communication bandwidth and programming efficiency. X265 is optimized on the OpenPOWER platform to improve its performance with both architecture specific methods and hardware-acceleration methods. For hardware acceleration, frame-level acceleration and functional-unit-level acceleration are introduced and evaluated in this work.