Hardware Efficient Integer Discrete Cosine Transform for Efficient Image/Video Compression

With the introduction of high efficiency video coding (HEVC) standard which provides super compression efficiency, there has been a lot of research works on integer transform matrices that can provide good approximation to the discrete cosine transform (DCT) used in HEVC. Not only maintaining the coding performance, the hardware and power of the circuit to implement the derived integer DCT (Int-DCT) needs to be minimized. To address these multiple design considerations, a new multi-objective optimization algorithm is proposed in this paper to search for efficient Int-DCT matrix, which has the coding performance as close as possible to the transform in HEVC but implemented with reduced hardware and power. Experimental results show that the approximated Int-DCT matrix generated by the proposed algorithm can achieve almost the same coding performance as the transforms in HEVC measured in terms of BjØntegaard Delta rate. Meanwhile, the experiments demonstrate that the proposed 16-point Int-DCT can produce at least 15.5% and 26.8% lower circuit area in FPGA and ASIC respectively, compared with other state-of-the-art Int-DCT realizations which can provide similar coding performance.