The present invention relates to technique for encoding and decoding an image. A method for decoding a video signal having a current block to be decoded according to the present invention includes obtaining a residual coefficient associated with the current block from a video signal and a transforming skip sign with respect to the current block, the transforming skip sign indicating whether the current block skips the inverse transformation; obtaining the inversely-quantized residual coefficient by performing inverse quantization on the residual coefficient; selectively performing the inversetransformation on the inversely quantized residual coefficient of the current block based on the transforming skip sign to obtain a residual sample; obtaining a reference sample of the current block based on a neighboring sample adjacent to the current block; obtaining a prediction sample of the current block based on an intra prediction mode of the current block and a reference sample of the current block; and using the residual samples and prediction samples to reconstruct the current block.