Methods and apparatus of encoding/decoding video picture partitioned in ctu grids

A method of decoding a video picture from a bitstream of encoded video picture data, wherein the method comprises:

• determining multiple grids of coding-tree units;
• each grid of coding-tree units covering a rectangular picture area of the video picture;
• a size of at least one rectangular picture area being different from an integer multiple of a default size of coding-tree unit decoded from the bitstream;
• each coding-tree unit representing a sub-area of a rectangular picture area, the sub-area being subdivided according to a coding tree;
• obtaining video picture data by decoding at least one coding unit (CU) of a coding tree associated with each coding tree unit (CTU) of each grid of coding-tree units from the bitstream;
• and
• obtaining the video picture from the video picture data.

An apparatus, comprising:

• a processor;
• and
• a memory storing programs executable by the processor;
• wherein the processor is configured to perform:
• determining multiple grids of coding-tree units;
• each grid of coding-tree units covering a rectangular picture area of the video picture;
• a size of at least one rectangular picture area being different from an integer multiple of a default size of coding-tree unit decoded from the bitstream;
• each coding-tree unit representing a sub-area of a rectangular picture area, the sub-area being subdivided according to a coding tree;
• obtaining video picture data by decoding at least one coding unit (CU) of a coding tree associated with each coding tree unit (CTU) of each grid of coding-tree units from the bitstream;
• and
• obtaining the video picture from the video picture data.