Spatial displacement vector prediction for intra picture block and string copying
A method, computer program, and computer system is provided for coding video data. Video data including one or more blocks is received. A current block coded in intra block copy mode or string matching mode is predicted from among the one or more blocks based on a coded block vector or a string offset vector corresponding to one or more spatial neighboring or non-neighboring blocks from among the one or more blocks. The video data is decoded based on the predicted current block.
1 . A method of video coding, executable by a processor, comprising:
receiving video bitstream comprising one or more blocks;
obtaining a displacement vector of a current block coded in an intra block copy (IBC) mode based on string offset vectors associated with one or more spatial non-neighboring blocks of the one or more blocks;
obtaining a string offset vector of the current block coded in a string matching mode based on block vectors associated with the one or more spatial non-neighboring blocks of the one or more blocks, wherein spatial candidates for obtaining the string offset vector are based on a history-based string offset vector candidates in a string offset vector predictor list, and a spatial neighboring block or a spatial non-neighboring block, location information, and size information are added to the string offset vector predictor list based on a class-based prediction being used, the class-based prediction comprising classification of a respective block vector associated with a respective history-based string offset vector candidate into at least one of:
a first class when an area of a coded block is greater than or equal to a threshold;
a second class when a frequency of a block vector is greater than or equal to 2;
a third class when the coded clock is located left of the current block;
a fourth class when the coded clock is located above of the current block;
a fifth class when the coded clock is located towards a top right of the current block; or
a sixth class when the coded clock is located towards a bottom left of the current block; and
decoding the video data based on the displacement vector of the current block or the string offset vector of the current block.
2 . The method of claim 1 , wherein only the one or more spatial non-neighboring blocks coded in the IBC mode are considered as candidates to predict the string offset vector of the current block coded in the string matching mode.
3 . The method of claim 1 , wherein the method further comprises:
one or more spatial neighboring blocks and the one or more spatial non-neighboring blocks being placed at a front of a string vector predictor list.
4 . The method of claim 1 , wherein the method further comprises:
one or more spatial neighboring blocks and the one or more spatial non-neighboring blocks being placed at an end of a string vector predictor list.
5 . The method of claim 1 , wherein only the one or more spatial non-neighboring blocks coded in the string matching mode are considered as candidates to predict the string offset vector of the current block coded in the string matching mode.
6 . The method of claim 1 , wherein only the one or more spatial neighboring blocks coded in the IBC mode are considered as candidates to predict the string offset vector of the current block coded in the string matching mode.
7 . A computer system for video coding, the computer system comprising:
one or more computer-readable non-transitory storage media configured to store computer program code; and
one or more computer processors configured to access said computer program code and operate as instructed by said computer program code, said computer program code including:
first predicting code configured to cause the one or more computer processors to determine a displacement vector of a current block coded in an intra block copy (IBC) mode based on string offset vectors associated with one or more spatial non-neighboring blocks oft one or more blocks,
second predicting code configured to cause the one or more computer processors to determine a string offset vector of the current block coded in a string matching mode based on block vectors associated with the one or more spatial non-neighboring blocks of the one or more blocks, wherein spatial candidates for obtaining the string offset vector are based on a history-based string offset vector candidates in a string offset vector predictor list, and a spatial neighboring block or a spatial non-neighboring block, location information, and size information are added to the string offset vector predictor list based on a class-based prediction being used, the class-based prediction comprising classification of a respective block vector associated with a respective history-based string offset vector candidate into at least one of:
a first class when an area of a coded block is greater than or equal to a threshold;
a second class when a frequency of a block vector is greater than or equal to 2;
a third class when the coded clock is located left of the current block;
a fourth class when the coded clock is located above of the current block;
a fifth class when the coded clock is located towards a top right of the current block; or
a sixth class when the coded clock is located towards a bottom left of the current block; and
encoding code configured to cause the one or more computer processors to encode the video data based on the displacement vector of the current block or the string offset vector of the current block.
8 . The computer system of claim 7 , wherein only the one or more spatial non-neighboring blocks coded in the IBC mode are considered as candidates to predict the string offset vector of the current block coded in the string matching mode.
9 . The computer system of claim 7 , wherein one or more spatial neighboring blocks and the one or more spatial non-neighboring blocks are placed at a front of a string vector predictor list.
10 . The computer system of claim 7 , wherein one or more spatial neighboring blocks and the one or more spatial non-neighboring blocks are placed at an end of a string vector predictor list.
11 . The computer system of claim 7 , wherein only the one or more spatial non-neighboring blocks coded in the string matching mode are considered as candidates to predict the string offset vector of the current block coded in the string matching mode.
12 . The computer system of claim 7 , wherein the one or more spatial neighboring blocks coded in the IBC mode are considered as candidates to predict the string offset vector of the current block coded in the string matching mode.
13 . A non-transitory computer readable medium having stored thereon a video bitstream that is generated by a video encoding method, the video encoding method comprising:
determining a displacement vector of a current block coded in an intra block copy (IBC) mode based on string offset vectors associated with one or more spatial non-neighboring blocks of one or more blocks;
determining a string offset vector of the current block coded in a string matching mode based on block vectors associated with the one or more spatial non-neighboring blocks of the one or more blocks, wherein spatial candidates for obtaining the string offset vector are based on a history-based string offset vector candidates in a string offset vector predictor list, and a spatial neighboring block or a spatial non-neighboring block, location information, and size information are added to the string offset vector predictor list based on a class-based prediction being used, the class-based prediction comprising classification of a respective block vector associated with a respective history-based string offset vector candidate into at least one of:
a first class when an area of a coded block is greater than or equal to a threshold;
a second class when a frequency of a block vector is greater than or equal to 2;
a third class when the coded clock is located left of the current block;
a fourth class when the coded clock is located above of the current block;
a fifth class when the coded clock is located towards a top right of the current block; or
a sixth class when the coded clock is located towards a bottom left of the current block; and
encoding the video bitstream comprising the current block based on the string offset vector.
14 . The non-transitory computer readable medium of claim 13 , wherein only the one or more spatial non-neighboring blocks coded in the IBC mode are considered as candidates to predict the string offset vector of the current block coded in the string matching mode.
15 . The non-transitory computer readable medium of claim 13 , wherein the bitstream further comprises the one or more spatial neighboring blocks and the one or more spatial non-neighboring blocks being placed at a front of or at an end of a string vector predictor list.