Methods and apparatus for multi-hypothesis mode reference and constraints

An apparatus configured to decode video data, the apparatus comprising a processor in communication with memory, the processor being configured to execute instructions stored in the memory that cause the processor to:

• determine if more than one hypothesis of prediction data are used for generating the prediction data of a current coding block of a picture, wherein when more than one hypothesis of prediction data is used for prediction of the current coding block of the picture:
• determine first prediction data for the current coding block of the picture generated using a first prediction mode;
• determine second prediction data for the current coding block generated using a second prediction mode;
• and
• storing information derived from at least one of the first prediction mode and the second prediction mode for the current coding block.

An encoding method for encoding video data, the method comprising:

• generating first prediction data for a current coding block of a picture using a first prediction mode;
• generating second prediction data for the current coding block using a second prediction mode;
• and
• storing information derived from at least one of the first prediction mode and the second prediction mode.