Method for padding processing with sub-region partitions in video stream

1. A method of video encoding, executable by a processor, the method comprising:

determining syntax elements corresponding to a wrap-around padding process based on shifting a reference block by a reference wrap-around padding width value, wherein the reference wrap-around padding width value is determined based on locations of luma samples in the reference block; and

encoding at least one picture using the wrap-around padding process, wherein the wrap- around padding process is applied at boundaries of subpictures.

2. The method of claim 1 , wherein the syntax elements indicate one of: an offset value for wrap-around processing, or left and right padding width information.

3. The method of claim 2 , wherein a flag indicates whether the syntax elements corresponding to the wrap-around padding process are present in a parameter set.

4. The method of claim 3 , wherein a pixel position for a motion compensated prediction in a reference picture is determined by interpreting the syntax elements corresponding to the wrap-around padding process with a clipping process.

5. The method of claim 4 , wherein a fractional pixel is interpolated for the motion compensated prediction based on the determined pixel position.

6. The method of claim 5 , wherein an overwrapped region is blended to remove a seam artifact as a post processing.

7. The method of claim 1 , wherein the wrap-around padding process is applied at a tile or a tile group boundary.

8. The method of claim 1 , wherein the at least one picture comprises a reference for motion compensation.

9. The method of claim 8 , wherein the wrap-around padding process is applied at a boundary of the at least one picture.

10. The method of claim 1 , wherein the wrap-around padding process is applied at a horizontal, a vertical boundary, or at both the vertical and horizontal boundaries.

11. The method of claim 10 , wherein a flag in a high level syntax structure indicates whether the wrap-around padding process is applied at the horizontal, the vertical boundary or both the vertical and horizontal boundaries.

12. A computer system for video coding, the computer system comprising:

one or more computer-readable non-transitory storage media configured to store program code; and

one or more computer processors configured to access said program code and operate as instructed by said program code, said program code including:

determining code configured to cause the one or more computer processors to determine syntax elements corresponding to a wrap-around padding process based on shifting a reference block by a reference wraparound padding width value, wherein the reference wrap-around padding width value is determined based on locations of luma samples in the reference block; and

encoding code configured to cause the one or more computer processors to encode at least one picture using the wrap-around padding process, wherein the wrap-around padding process is applied at boundaries of subpictures.

13. The computer system of claim 12 , wherein the syntax elements indicate one of: an offset value for wrap-around processing, or left and right padding width information.

14. The computer system of claim 13 , wherein a flag indicates whether the syntax elements corresponding to the wrap-around padding process are present in a parameter set.

15. The computer system of claim 14 , wherein a pixel position for a motion compensated prediction in a reference picture is determined by interpreting the syntax elements corresponding to the wrap-around padding process with a clipping process.

16. The computer system of claim 15 , wherein a fractional pixel is interpolated for the motion compensated prediction based on the determined pixel position.

17. The computer system of claim 16 , wherein an overwrapped region is blended to remove a seam artifact as a post processing.

18. The computer system of claim 12 , wherein the wrap-around padding process is applied at a tile or a tile group boundary.

19. The computer system of claim 12 , wherein the at least one picture is a reference for motion compensation.

20. A non-transitory computer readable medium having stored thereon a program for video coding, the program configured to cause one or more computer processors to:

determine syntax elements corresponding to a wrap-around padding process based on shifting a reference block by a reference wrap-around padding width value, wherein the reference wrap-around padding width value is determined based on locations of luma samples in the reference block; and

encode at least one picture using the wrap-around padding process, wherein the wrap- around padding process is applied at boundaries of subpictures.