Derivation method and apparatuses with candidate motion vectors
Various embodiments for coding a current block are provided. One or more candidates of a first type for a motion vector predictor for the current block are derived from first motion vectors of first blocks. A candidate of a second type for the motion vector predictor for the current block is derived. The candidate of the second type is different from the one or more candidates of the first type and includes a zero vector. The motion vector predictor for the current block is selected from among candidates including the one or more candidates of the first type and the candidate of the second type. The current block is predicted using the selected motion vector predictor. A bitstream is generated using the predicted current block. A total number of the one or more candidates of the first type is less than a maximum candidate number.
1. A method for coding a current block, the method comprising:
deriving one or more candidates of a first type for a motion vector predictor for the current block from first motion vectors of first blocks;
deriving one or more candidates of a second type for the motion vector predictor for the current block until a total number of the one or more candidates of the first type and the one or more candidates of the second type reaches a maximum candidate number, each of the one or more candidates of the second type being different from the one or more candidates of the first type and including a zero vector;
selecting the motion vector predictor for the current block from among a plurality of candidates including the one or more candidates of the first type and the candidate of the second type;
predicting the current block using the selected motion vector predictor for the current block; and
generating a bitstream using the predicted current block,
wherein the deriving of the one or more candidates of the second type includes:
deleting one of the one or more candidates of the first type; and
adding one of the one or more candidates of the second type after the deleting of the one of the one or more candidates of the first type.
2. A coding apparatus which codes a current block, the coding apparatus comprising:
a processor; and
a non-transitory storage,
the processor performing, using the non-transitory storage, processes including:
deriving one or more candidates of a first type for a motion vector predictor for the current block from first motion vectors of first blocks stored in the non-transitory storage;
deriving one or more candidates of a second type for the motion vector predictor for the current block until a total number of the one or more candidates of the first type and the one or more candidates of the second type reaches a maximum candidate number, each of the one or more candidates of the second type being different from the one or more candidates of the first type and including a zero vector;
selecting the motion vector predictor for the current block from among a plurality of candidates including the one or more candidates of the first type and the candidate of the second type;
predicting the current block using the selected motion vector predictor for the current block; and
generating a bitstream using the predicted current block,
wherein the deriving of the one or more candidates of the second type includes:
deleting one of the one or more candidates of the first type; and
adding one of the one or more candidates of the second type after the deleting of the one of the one or more candidates of the first type.