Granted Patent B2

US 12,309,406 · App. 17/788,188 · Granted May 20, 2025

Inventor: Sachin G. Deshpande (Vancouver, WA)

Assignee: SHARP KABUSHIKI KAISHA

H04N19/44H04N19/176H04N19/70

Abstract

Claims (21)

1. A method of decoding video data, the method comprising:

parsing a first syntax element, wherein the first syntax element plus 1 indicates a number of subpictures in a picture;

for each of the subpictures other than a first subpicture, parsing second syntax elements indicating a position of each of the subpictures other than the first subpicture;

inferring a top-left position of the first subpicture equal to a top-left position of the picture;

for each of the subpictures other than a last subpicture, parsing a third syntax element and a fourth syntax element, wherein the third syntax element plus 1 indicates a width of each of the subpictures other than the last subpicture and the fourth syntax element plus 1 indicates a height of each of the subpictures other than the last subpicture;

inferring a value of the third syntax element of the last subpicture to be equal to a maximum picture width in coding tree blocks—a horizontal position of a top-left coding tree unit of the last subpicture specified by one of the second syntax elements−1; and

inferring a value of the fourth syntax element of the last subpicture to be equal to a maximum picture height in coding tree blocks—a vertical position of a top-left coding tree unit of the last subpicture specified by one of the second syntax elements−1,

wherein,

parsing the third syntax element includes determining a length in bits of the third syntax element based on Ceil(Log2((maximum picture width in luma samples+coding tree block width in luma samples−1)/coding tree block width in luma samples)), and

parsing the fourth syntax element includes determining a length in bits of the fourth syntax element based on Ceil(Log2((maximum picture height in luma samples+coding tree block height in luma samples−1)/coding tree block height in luma samples)).

2. A device comprising one or more processors configured to:

parse a first syntax element, wherein the first syntax element plus 1 indicates a number of subpictures in a picture;

for each of the subpictures other than a first subpicture, parse second syntax elements indicating a position of each of the subpictures other than the first subpicture;

infer a top-left position of the first subpicture equal to a top-left position of the picture;

for each of the subpictures other than a last subpicture, parse a third syntax element and a fourth syntax element, wherein the third syntax element plus 1 indicates a width of each of the subpictures other than the last subpicture and the fourth syntax element plus 1 indicates a height of each of the subpictures other than the last subpicture;

infer a value of the third syntax element of the last subpicture to be equal to a maximum picture width in coding tree blocks—a horizontal position of a top-left coding tree unit of the last subpicture specified by one of the second syntax elements−1; and

infer a value of the fourth syntax element of the last subpicture to be equal to a maximum picture height in coding tree blocks—a vertical position of a top-left coding tree unit of the last subpicture specified by one of the second syntax elements−1,

wherein,

a length in bits of the third syntax element is determined based on Ceil(Log2((maximum picture width in luma samples+coding tree block width in luma samples−1)/coding tree block width in luma samples)), and

a length in bits of the fourth syntax element is determined based on Ceil(Log2((maximum picture height in luma samples+coding tree block height in luma samples−1)/coding tree block height in luma samples).

3. The device of claim 2 , wherein the device is a video decoder.

Assignments (1)

Continuity (2)

References Cited (15)