Method and apparatus for coefficient scan based on partition mode of prediction unit

A method of decoding a video signal having a current block to be decoded with a decoding apparatus, comprising:

• obtaining index information relating to the current block from the video signal, the index information being signaled to select a collocated picture from a plurality of previously decoded pictures,
• the collocated picture being representative of a picture including a collocated block which is used to derive a temporal motion vector candidate of the current block;
• obtaining a spatial motion vector candidate from a spatial neighboring block of the current block;
• selecting, based on the index information, the collocated picture relating to the temporal motion vector candidate of the current block from the plurality of the previously decoded pictures;
• obtaining the temporal motion vector candidate from the collocated block included in the selected collocated picture;
• generating a motion vector candidate list using the spatial motion vector candidate and the temporal motion vector candidate;
• deriving a motion vector predictor based on the motion vector candidate list and a candidate index of the current block,
• the candidate index specifying one of motion vector candidates included in the motion vector candidate list;
• obtaining prediction samples of the current block by using the motion vector predictor;
• obtaining residual samples relating to the current block by performing an inverse quantization and an inverse-transform on coefficients from the video signal;
• and
• reconstructing the current block by using the prediction samples and the residual samples,
• wherein the collocated picture has a temporal order different from a current picture including the current block,
• and the collocated block corresponds to a position as the current block.