Video signal processing method and device

A device for decoding a video signal, the device comprising a processor and a memory, wherein, based on instructions stored in the memory, the processor is configured to:

• obtain chroma component format information from a higher-level bitstream;
• obtain width-related information (SubWidthC) and height-related information (SubHeightC) based on the chroma component format information;
• obtain x-axis scale information based on the width-related information or information on a color component of a current block;
• obtain y-axis scale information based on the height-related information or information on the color component of the current block;
• determine a location of a left block based on the y-axis scale information;
• determine a location of an upper block based on the x-axis scale information;
• determine a weighting value based on the left block and the upper block;
• obtain first samples by predicting the current block in a merge mode;
• obtain second samples by predicting the current block in an intra mode;
• and
• obtain a combination prediction sample for the current block as a weighted sum of the first samples and the second samples using the weighting value.

A method for generating a bitstream including a video signal, the method comprising:

• generating chroma component format information;
• obtaining width-related information (SubWidthC) and height-related information (SubHeightC) based on the chroma component format information;
• obtaining x-axis scale information based on the width-related information or information on a color component of a current block;
• obtaining y-axis scale information based on the height-related information or information on the color component of the current block;
• determining a location of a left block based on the y-axis scale information;
• determining a location of an upper block based on the x-axis scale information;
• determining a weighting value based on the left block and the upper block;
• obtaining first samples by predicting the current block in a merge mode;
• obtaining second samples by predicting the current block in an intra mode;
• and
• obtaining a combination prediction sample for the current block as a weighted sum of the first samples and the second samples using the weighting value.

A non-transitory computer-readable medium storing a bitstream, the bitstream being decoded by a decoding method,

• wherein the decoding method comprises:
• obtaining chroma component format information from a higher-level bitstream;
• obtaining width-related information (SubWidthC) and height-related information (SubHeightC) based on the chroma component format information;
• obtaining x-axis scale information based on the width-related information or information on a color component of a current block;
• obtaining y-axis scale information based on the height-related information or information on the color component of the current block;
• determining a location of a left block based on the y-axis scale information;
• determining a location of an upper block based on the x-axis scale information;
• determining a weighting value based on the left block and the upper block;
• obtaining first samples by predicting the current block in a merge mode;
• obtaining second samples by predicting the current block in an intra mode;
• and
• obtaining a combination prediction sample for the current block as a weighted sum of the first samples and the second samples using the weighting value.