Method for storing motion information and method for inducing temporal motion vector predictor using same

A method for inter prediction, by a decoding apparatus, comprising:

• determining a positioning pixel for a temporal motion vector predictor (TMVP) of a current block of a current picture;
• deriving a co-located prediction block (colPb) in a reference picture based on the positioning pixel;
• deriving the temporal motion vector predictor (TMVP) of the current block of a current picture based on a motion vector of the co-located prediction block (colPb) in the reference picture;
• and
• performing inter prediction for the current block based on the TMVP derived based on the motion vector of the colPb in the reference picture,
• wherein the co-located prediction block (colPb) is a prediction block covering a modified location that is determined based on a location of the positioning pixel, and
• wherein the positioning pixel is determined as a pixel at a right-bottom side among four pixels located at the center of a co-located block in the reference picture, wherein the co-located block is a block corresponding to the current block and located in the reference picture.

A decoding apparatus for decoding a video, comprising:

• a prediction module for determining a positioning pixel for a temporal motion vector predictor (TMVP) of a current block of a current picture, for deriving a co-located prediction block (colPb) in a reference picture based on the positioning pixel, for deriving the temporal motion vector predictor (TMVP) of the current block of a current picture based on a motion vector of the co-located prediction block (colPb) in the reference picture, and for performing inter prediction for the current block based on the TMVP derived based on the motion vector of the colPb in the reference picture;
• and
• a memory for storing the motion vector of the co-located prediction block (colPb) in the reference picture,
• wherein the co-located prediction block (colPb) is a prediction block covering a modified location that is determined based on a location of the positioning pixel, and
• wherein the positioning pixel is determined as a pixel at a right-bottom side among four pixels located at the center of a co-located block in the reference picture, wherein the co-located block is a block corresponding to the current block and located in the reference picture.