UPDATE OF LOOK UP TABLE: FIFO, CONSTRAINED FIFO
A method of video processing is provided to include maintaining one or more tables, wherein each table includes one or more motion candidates and each motion candidate is associated with corresponding motion information; performing a conversion between a current block and a bitstream representation of a video including the current block by using motion information in a table; and updating, after performing of the conversion, one or more tables based on M sets of additional motion information associated with the current block, M being an integer.
1 . A method of processing video data, comprising
determining motion information of a current video block of a video;
coding the current video block based on the determined motion information; and
updating a table using a new motion candidate corresponding to the determined motion information;
wherein the table comprises one or more motion candidates derived from one or more video blocks that have been coded, and at least one motion candidate is removed from the table, due to the at least one motion candidate being identified as a redundancy of current motion candidates by a redundancy checking before adding the new motion candidate into the table, wherein at least one motion candidate in the table is checked during determination of motion information of a subsequent video block.
2 . The method of claim 1 , wherein the coding comprises generating a bitstream representation from the current video block.
3 . The method of claim 1 , wherein the coding comprises generating the current video block from a bitstream representation.
4 . The method of claim 1 , wherein the determination of motion information of a subsequent video block comprises:
checking at least one motion candidate in the table during construction of a motion candidate list; and
deriving the motion information using the motion candidate list.
5 . The method of claim 1 , wherein the redundancy checking is performed in an order that the current motion candidates have been added to the table or in an order of a coding process of blocks from where the current motion candidates in the table have been obtained.
6 . The method of claim 1 , wherein the redundancy checking is performed in an order from a first motion candidate with a minimum index in the table to a last motion candidate with a maximum index in the table.
7 . The method of claim 1 , wherein the redundancy checking is terminated when a redundant motion candidate in the table is identified.
8 . The method of claim 1 , wherein redundancy checking comprises comparing motion candidates in the table with the new motion candidate.
9 . The method of claim 1 , wherein when at least one of current motion candidates in the table is redundant to the new motion candidate, the counter indicating a number of motion candidates in the table is not increased.
10 . The method of claim 1 , wherein indices of the motion candidates in the table is based on a sequence of addition of the motion candidates into the table.
11 . The method of claim 10 , wherein when the new motion candidate is added into the table, the new motion candidate has an index greater than other motion candidates in the table.
12 . The method of claim 10 , wherein the at least one motion candidate in the table is checked in an order of at least one index of the at least one motion candidate during determination of motion information of the subsequent block.
13 . The method of claim 10 , wherein the sequence of addition of the candidates into the table is based on a sequence of coding blocks from which the candidates are derived.
14 . The method of claim 1 , wherein the at least one motion candidate is removed from the table to provide an empty entry in the table and motion candidates whose indices are greater than that of the at least one motion candidate are moved forward to fill the empty entry and the addition of the new motion candidate into the table is performed after the moving of the motion candidates.
15 . The method of claim 1 , wherein a motion candidate in the table comprises motion information different from any other motion candidates in the table.
16 . The method of claim 1 , wherein a motion vector (MV) difference between an MV of a motion candidate in the table and an MV of a same reference picture of another motion candidate is not smaller than a threshold.
17 . The method of claim 1 , wherein the updating is performed if at least one condition is satisfied, wherein the at least one condition is based on at least one of a coding mode of current video block or source of motion information of a corresponding motion candidate.
18 . The method of claim 1 , wherein a motion candidate in the table is associated with motion information including at least one of: a block position information to indicate from which the motion information is coming, a prediction direction, a reference picture index, motion vector values, an intensity compensation flag, an affine flag, a motion vector difference precision, or motion vector difference value.
19 . A video processing apparatus comprising a processor and a non-transitory memory with instructions thereon, wherein the instructions upon execution by the processor, cause the processor to:
determine motion information of a current video block of a video;
code the current video block based on the determined motion information; and
update a table using a new motion candidate corresponding to the determined motion information;
wherein the table comprises one or more motion candidates derived from one or more video blocks that have been coded, and at least one motion candidate is removed from the table, due to the at least one motion candidate being identified as a redundancy of current motion candidates by a redundancy checking before adding the new motion candidate into the table, wherein at least one motion candidate in the table is checked during determination of motion information of a subsequent video block.
20 . A non-transitory computer-readable storage medium storing instructions that cause a processor to:
determine motion information of a current video block of a video;
code the current video block based on the determined motion information; and
update a table using a new motion candidate corresponding to the determined motion information;
wherein the table comprises one or more motion candidates derived from one or more video blocks that have been coded, and at least one motion candidate is removed from the table, due to the at least one motion candidate being identified as a redundancy of current motion candidates by a redundancy checking before adding the new motion candidate into the table, wherein at least one motion candidate in the table is checked during determination of motion information of a subsequent video block.
21 . A non-transitory computer-readable recording medium storing a bitstream representation which is generated by a method performed by a video processing apparatus, wherein the method comprises:
determining motion information of a current video block of a video;
generating the bitstream representation from the current video block based on the determined motion information; and
updating a table using a new motion candidate corresponding to the determined motion information;
wherein the table comprises one or more motion candidates derived from one or more video blocks that have been coded, and at least one motion candidate is removed from the table, due to the at least one motion candidate being identified as a redundancy of current motion candidates by a redundancy checking before adding the new motion candidate into the table, wherein at least one motion candidate in the table is checked during determination of motion information of a subsequent video block.