Computation Reduction in Transform Unit of High Efficiency Video Coding Based on Zero-Coefficients
Jiunn-Tsair Fang, Yu-Chen Tsai, Jia-Xun Lee, Pei-Shan Yu · 2016
The new video coding standard, high efficiency video coding (HEVC) had been finalized in 2013. Its transform unit (TU) adopts a quadtree structure to provide variable sizes of integer discrete cosine transform (DCT) for transform coding. The quadtree structure of TU increases the coding efficiency, but the computational complexity also increases, compared with previous video coding standards. Thus, reducing TU processing time becomes essential. For a TU block, if all its coefficients are zero, this TU may have the lowest rate-distortion (R-D) cost during the R-D optimization procedure. The following procedures for this TU can be terminated. Experiments show that the proposed method saved approximately 38% of TU processing time, with little bit rate increased, and the PSNR performance was almost the same.