Merge mode with motion vector differences

An electronic apparatus comprising:

• one or more processing units;
• memory coupled to the one or more processing units;
• and
• a plurality of programs stored in the memory that, when executed by the one or more processing units, cause the electronic apparatus to perform a method of encoding video data comprising:
• in response to a determination that merge mode with motion vector difference (MMVD) is enabled for one or more coding units in a video sequence,
• generating a first syntax element, wherein the first syntax element identifies a set of motion vector difference (MVD) offsets from a plurality sets of MVD offsets, wherein each set of the plurality sets of MVD offsets comprises a plurality of MVD offsets and the plurality sets of MVD offsets comprise a first set of MVD offsets and a second set of MVD offsets, wherein a first set of binarization codewords is assigned to the first set of MVD offsets, and a second set of binarization codewords is assigned to the second set of MVD offsets, and wherein a codeword for an offset value in the first set of binarization codewords is different from a codeword for the offset value in the second set of binarization codewords;
• and
• in response to a determination that the MMVD is applied to a respective coding unit of the one or more coding units,
• generating a second syntax element, which is different from the first syntax element, for the respective coding unit that selects an MVD offset from the identified set of MVD offsets, and a third syntax element, which is different from the first syntax element, for the respective coding unit that selects an MVD direction corresponding to the selected MVD offset;
• and
• reconstructing the respective coding unit by applying the selected MVD offset and MVD direction to generate motion vectors for the respective coding unit.

A method for storing a bitstream, comprising:

• generating a bitstream by performing an encoding method;
• and
• storing the bitstream,
• wherein the encoding method comprises:
• in response to a determination that merge mode with motion vector difference (MMVD) is enabled for one or more coding units in a video sequence,
• generating a first syntax element, wherein the first syntax element identifies a set of motion vector difference (MVD) offsets from a plurality sets of MVD offsets, wherein each set of the plurality sets of MVD offsets comprises a plurality of MVD offsets and the plurality sets of MVD offsets comprise a first set of MVD offsets and a second set of MVD offsets, wherein a first set of binarization codewords is assigned to the first set of MVD offsets, and a second set of binarization codewords is assigned to the second set of MVD offsets, and wherein a codeword for an offset value in the first set of binarization codewords is different from a codeword for the offset value in the second set of binarization codewords;
• and
• in response to a determination that the MMVD is applied to a respective coding unit of the one or more coding units,
• generating a second syntax element, which is different from the first syntax element, for the respective coding unit that selects an MVD offset from the identified set of MVD offsets, and a third syntax element, which is different from the first syntax element, for the respective coding unit that selects an MVD direction corresponding to the selected MVD offset;
• and
• reconstructing the respective coding unit by applying the selected MVD offset and MVD direction to generate motion vectors for the respective coding unit.