US 11,930,174 B2
Method and apparatus of luma-chroma separated coding tree coding with constraints
Chia-Ming Tsai, Hsinchu (TW); Tzu-Der Chuang, Hsinchu (TW); Chih-Wei Hsu, Hsinchu (TW); Ching-Yeh Chen, Hsinchu (TW); and Zhi-Yi Lin, Hsinchu (TW)
Assigned to HFI INNOVATION INC., Zhubei (TW)
Appl. No. 17/418,311
Filed by MEDIATEK INC., Hsinchu (TW)
PCT Filed Dec. 30, 2019, PCT No. PCT/CN2019/130044
§ 371(c)(1), (2) Date Jun. 25, 2021,
PCT Pub. No. WO2020/140876, PCT Pub. Date Jul. 9, 2020.
Claims priority of provisional application 62/865,397, filed on Jun. 24, 2019.
Claims priority of provisional application 62/786,530, filed on Dec. 30, 2018.
Prior Publication US 2022/0086439 A1, Mar. 17, 2022
Int. Cl. H04N 19/119 (2014.01); H04N 19/176 (2014.01); H04N 19/186 (2014.01); H04N 19/96 (2014.01)
CPC H04N 19/119 (2014.11) [H04N 19/176 (2014.11); H04N 19/186 (2014.11); H04N 19/96 (2014.11)] 4 Claims
OG exemplary drawing
 
1. A method of video coding used by a video coding system, the method comprising:
receiving input data associated with a current block in a current picture, wherein the input data comprise pixel data to be encoded at an encoder side or compressed data at a decoder side, and wherein the current block comprises a luma block and a chroma block;
when separate partition trees are allowed for the luma block and the chroma block, partitioning the luma block into one or more luma leaf blocks using a luma partition tree and partitioning the chroma block into one or more chroma leaf blocks using a chroma partition tree;
determining whether one or more exception conditions to allow an LM (Linear Mode) for a target chroma leaf block is satisfied when the chroma partition tree uses a different split type, a different partition direction, or both from the luma partition tree; and
encoding or decoding the target chroma leaf block using the LM mode when the chroma partition tree is different from the luma partition tree and at least one of the one or more exception conditions is satisfied,
wherein:
said one or more exception conditions comprise a case that the luma block being a luma 64×64 block is partitioned into four luma 32×32 blocks using a QT (quadtree) split and the chroma block being a chroma 32×32 block is partitioned into two chroma 32×16 blocks using a horizontal BT (binary tree) split with no further split or partitioned into four chroma 16×16 blocks using the horizontal BT split followed by a vertical BT split;
or
said one or more exception conditions comprise a case that the chroma block is partitioned into one or more split chroma CUs (coding units) and each of said one or more split chroma CUs cover and contain one or more complete luma CUs resulted from partitioning the luma block using the luma partition tree, and wherein coding order of said one or more complete luma CUs are continuous.