Patent ID: 9723311
Date: 2017-08-01
CPC Classifications: H04N

Claim:
1. A video decoding method comprising: obtaining first information indicating whether a residual signal is present in a current block, the current block including one or more transform coefficient levels other than 0 when the first information indicates that the residual signal is present in the current block; when the first information indicates that the residual signal is present in the current block, obtaining the residual signal of the current block based on a scanning direction (scanIdx) for the residual signal of the current block, the scanning direction for the residual signal of the current block being determined based on an intra prediction mode of the current block, the scanning direction for the residual signal of current block being determined to be a vertical scan, a horizontal scan or an upper right scan; obtaining second information indicating whether an inverse-transform is performed on the residual signal of the current block; determining a transform type of the current block when the second information indicates that the inverse-transform is performed on the current block; obtaining residual samples of the current block by performing the inverse-transform on the residual signal of the current block based on the determined transform type; performing an intra prediction on the current block based on the intra prediction mode of the current block; and reconstructing the current block based on the residual samples and prediction samples, wherein the transform type of the current block is determined to be a DCT (Discrete Cosine Transform) or a DST (Discrete Sine Transform), and wherein the transform type of the current block is determined independently to the intra prediction mode of the current block.