Patent ID: 9294775
Filing Date: 2016-03-22
CPC Classification: H04N

Claim Text:
1. A method of decoding a video signal having a current block to be decoded with a decoding apparatus, comprising: obtaining quantized coefficients of the current block from the video signal; obtaining inverse-quantized coefficients of the current block by inverse-quantizing the quantized coefficients; obtaining, based on a transform skip flag specifying whether an inverse-transform is skipped for the current block, residual samples from the inverse-quantized coefficients of the current block, wherein when the transform skip flag is equal to 0, the residual samples are obtained by performing the inverse-transform for the inverse-quantized coefficients of the current block, and when the transform skip flag is equal to 1, the residual samples are obtained by skipping the inverse-transform for the inverse-quantized coefficients of the current block; obtaining prediction samples of the current block based on prediction mode information of the current block, the prediction mode information indicating whether the current block is an inter-coded block or an intra-coded block; and reconstructing the current block by using the residual samples and the prediction sample, wherein when the transform skip flag specifies that the inverse-transform is performed for the current block, the obtaining of the residual samples comprises: determining, based on at least one of the prediction mode information of the current block or a size of a transform block relating to the current block, whether a transform type of the current block is a discrete cosine transform (DCT) or a discrete sine transform (DST); and performing the inverse-transform for the inverse-quantized coefficients of the current block by using the determined transform type.