Transform with residual rearrangement for HEVC intra coding

摘要

In video compression, transformation plays a significant role in the energy compaction of spatial domain data into frequency domain data. In the HEVC intra prediction, Discrete Cosine Transform (DCT) and Discrete Sine Transform (DST) are used to concentrate the spatial residual signals into low-frequency components. DCT has shown good compression performance in both intra and inter residual coding, but when the spatial residual signals are not uniformly distributed, its coding efficiency decreases. This paper proposes a transform method that applies DCT or residual-rearranged DST to improve the coding efficiency in HEVC intra coding. The proposed method selects the best transform in terms of coding efficiency between the DCT and residual-rearranged DST for all block sizes. The experimental results show that, compared with the HEVC intra coding, the proposed method reduces the luma Bjontegaard Delta (BD) rates by 2.6%.