Chroma sample weight derivation for geometric partition mode

A video decoder, comprising:

• one or more processors;
• and
• a non-transitory computer-readable storage medium coupled to the one or more processors and storing programming instructions for execution by the one or more processors, wherein the one or more processors, upon executing the programming instructions, cause the video decoder to carry out operations of:
• obtaining a value of a parameter for a current block, the value of the parameter indicating a partition mode for the current block;
• obtaining a first prediction mode for the current block;
• obtaining a second prediction mode for the current block;
• generating a first prediction value for a chroma sample in the current block according to the first prediction mode;
• generating a second prediction value for a chroma sample in the current block according to the second prediction mode;
• obtaining a combined prediction value by combining the first prediction value and the second prediction value.

A non-transitory computer-readable medium having stored thereon instructions that, when executed by one or more processors, cause the one or more processors to perform operations including:

• obtaining a value of a parameter for a current block, the value of the parameter indicating a partition mode for the current block;
• obtaining a first prediction mode for the current block;
• obtaining a second prediction mode for the current block;
• generating a first prediction value for a chroma sample in the current block according to the first prediction mode;
• generating a second prediction value for a chroma sample in the current block according to the second prediction mode;
• obtaining a combined prediction value by combining the first prediction value and the second prediction value.