Method and apparatus for encoding and decoding image, and recording medium for storing bitstream

An image encoding method comprising:

• deriving a temporal merge candidate from a co-located block of a current block;
• generating a merge candidate list of the current block, based on the derived temporal merge candidate;
• and
• generating a prediction block of the current block, based on the generated merge candidate list,
• wherein the deriving a temporal merge candidate comprises:
• scaling a motion vector derived from the co-located block, based on a POC difference value between the current block and a reference picture of the current block and a POC difference value between the co-located block and a reference picture of the co-located block;
• and
• modifying the scaled motion vector, based on motion vector scaling information between spatial and temporal neighboring blocks of the current block and co-located blocks of the spatial and temporal neighboring blocks.

An image decoding method comprising:

• acquiring an inter-picture prediction indicator indicating an inter-picture prediction direction and an inter-picture prediction mode;
• and
• generating a prediction block of a current block based on the inter-picture prediction indicator,
• wherein the inter-picture prediction indicator indicates the inter-picture prediction mode for each prediction direction.

An image decoding apparatus comprising:

• a motion compensation unit deriving a temporal merge candidate from a co-located block of a current block, generating a merge candidate list based on the derived temporal merge candidate, and generating a prediction block of the current block based on the generated merge candidate list,
• wherein the motion compensation unit performs:
• scaling a motion vector derived from the co-located block based on a POC difference value between the current block and a reference picture of the current block and a POC difference value between the co-located block and a reference picture of the co-located block;
• and
• modifying the scaled the motion vector based on motion vector scaling information between a neighboring block of the current block and a co-located block of the neighboring block.

An image decoding apparatus comprising:

• an entropy decoding unit acquiring an inter-picture prediction indicator indicating an inter-picture prediction direction and an inter-picture prediction mode;
• and
• a motion compensation unit generating a prediction block of a current block based on the inter-picture prediction indicator,
• wherein the inter-picture prediction indicator indicates an inter-picture prediction mode for each prediction direction.