Image encoding/decoding method and apparatus, and recording medium for storing bitstream

An image encoding method performed by an encoding apparatus, the method comprising:

• deriving a collocated picture of a current block;
• determining whether a collocated block in the collocated picture is available as a temporal merge candidate of the current block based on a prediction mode of the collocated block;
• based on the collocated block being available as the temporal merge candidate, deriving the temporal merge candidate of the current block based on motion information of the collocated block;
• generating a merge candidate list based on the temporal merge candidate of the current block;
• deriving motion information of the current block based on the merge candidate list;
• deriving a prediction sample of the current block based on the motion information;
• deriving a residual sample of the current block based on the prediction sample;
• and
• encoding image information including residual information and information for the collocated picture of the current block,
• wherein based on the prediction mode of the collocated block being a current picture referencing (CPR) mode, the collocated block is not available as the temporal merge candidate, and
• wherein the CPR mode is a prediction mode in which a current picture including the current block is used as a reference picture.

A transmission method for image data, the method comprising:

• obtaining a bitstream of encoded image information, wherein the encoded image information is generated based on deriving a collocated picture of a current block, determining whether a collocated block in the collocated picture is available as a temporal merge candidate of the current block based on a prediction mode of the collocated block, based on the collocated block being available as the temporal merge candidate, deriving the temporal merge candidate of the current block based on motion information of the collocated block, generating a merge candidate list based on the temporal merge candidate of the current block, deriving motion information of the current block based on the merge candidate list, deriving a prediction sample of the current block based on the motion information, deriving a residual sample of the current block based on the prediction sample, and encoding the image information including residual information and information for the collocated picture of the current block;
• and
• transmitting the image data comprising the bitstream,
• wherein based on the prediction mode of the collocated block being a current picture referencing (CPR) mode, the collocated block is not available as the temporal merge candidate, and
• wherein the CPR mode is a prediction mode in which a current picture including the current block is used as a reference picture.