1. A method for decoding a video signal, comprising: decoding a base layer image in a base layer; obtaining first phase shift information between a luma sample and a chroma sample in an enhanced layer; determining whether second phase shift information between a luma sample and a chroma sample in the base layer is transmitted; obtaining the second phase shift information in the base layer according to the determining step; obtaining offset information indicating a position difference between at least one boundary pixel of an up-sampled image and at least one boundary pixel of a current image in the enhanced layer for an inter-layer prediction between the base layer and the enhanced layer, wherein the enhanced layer differs from the base layer in an aspect ratio or a spatial resolution, the up-sampled image representing an up-sampled base layer image; performing motion prediction to decode an inter-coded block of the current image in the enhanced layer using a motion vector of the base layer; and performing texture prediction to decode an intra-coded block of the current image in the enhanced layer based on the base layer image, the performing texture prediction comprising: (1) obtaining reference pixel values in the base layer based on the first phase shift information, the second phase shift information and the offset information; and (2) decoding the intra-coded block in the enhanced layer based on the reference pixel values.