Flexible band offset mode in sample adaptive offset in hevc

Patent metadata

Field	Value
Publication number	US-2021006810-A1
Application number	US-202016902483-A
Country	US
Kind code	A1
Filing date	Jun 16, 2020
Priority date	Jan 20, 2012
Publication date	Jan 7, 2021
Grant date	—

Abstract

A Flexible Band Offset (FBO) apparatus and method of performing Sample Adaptive Offset (SAO) filtering within encoders and decoders, such as according to the High Efficiency Video Coding (HEVC) standard, and similarly configured coding devices. The number of Band Offset (BO) modes and the number of necessary offsets is reduced. The invention beneficially provides simpler coding, reduces temporary buffer size requirements, and can yield a small performance gain over existing SAO techniques of HEVC test model HM 5.

First claim

1 . (canceled)

2 . An encoding device, comprising:
a setting unit configured to:
set a head band and a plurality of bands other than the head band included in a plurality of consecutive bands, based on a modulo remainder in a band offset mode in which an offset is applied to each band indicating a range of a plurality of pixel values, wherein the modulo remainder is based on a total number of bands for a number of the head band located at a head of the plurality of consecutive bands; and
set the offset for each of the plurality of consecutive bands, wherein the plurality of consecutive bands applies the offset to multiply divided bands; and
an encoding unit configured to:
encode an image; and
generate a bit stream, wherein the bit stream includes the offset set by the setting unit and position data that indicates the number of the head band.

3 . The encoding device according to claim 2 , wherein the setting unit is further configured to set the position data that indicates the number of the head band.

4 . The encoding device according to claim 2 , wherein the plurality of consecutive bands are four consecutive bands which are determined by selection of a position of the head band from 32 bands.

5 . The encoding device according to claim 4 , wherein the setting unit is further configured to set the plurality of bands other than the head band, from the plurality of consecutive bands by use of the modulo remainder based on (the number of the head band+i) %32, wherein 0≤i≤3.

6 . The encoding device according to claim 2 , further comprising
an offset processing unit configured to apply the offset set by the setting unit to a plurality of pixels, of a decoded image, belonging to the plurality of consecutive bands, wherein the decoded image is decoded as an object, wherein the encoding unit is further configured to encode the image with the decoded image to which the offset is applied by the offset processing unit.

7 . The encoding device according to claim 6 , further comprising
a filter unit configured to apply a deblocking filter on a decoded image, wherein the deblocking filter is applied by the filter unit as an object, wherein the offset processing unit is further configured to apply the offset to the plurality of pixels, of the deblock filtered decoded image, of the plurality of consecutive bands.

8 . The encoding device according to claim 7 , wherein the encoding unit is further configured to encode the image for each of coding units divided with a quadtree segmentation.

9 . The encoding device according to claim 8 , wherein the coding units are divided into prediction units and transform units.

10 . An image encoding method, comprising:
setting a head band and a plurality of bands other than the head band included in a plurality of consecutive bands, based on a modulo remainder in a band offset mode in which an offset is applied to each band indicating a range of a plurality of pixel values, wherein the modulo remainder is based on a total number of bands for a number of the head band located at a head of the plurality of consecutive bands; setting the offset for each of the plurality of consecutive bands, wherein the plurality of consecutive bands applies the offset to multiply divided bands; encoding an image; and generating a bit stream, wherein the bit stream includes the offset set and position data that indicates the number of the head band.

11 . The method according to claim 10 , further comprising setting the position data that indicates the number of the head band.

12 . The method according to claim 10 , wherein the plurality of consecutive bands are four consecutive bands which are determined by selecting a position of the head band from 32 bands.

13 . The method according to claim 12 , further comprising setting the plurality of bands other than the head band, from the plurality of consecutive bands by using the modulo remainder based on (the number of the head band+i) %32, wherein 0≤i≤3.

14 . The method according to claim 10 , further comprising:
applying the set offset to a plurality of pixels, of a decoded image, belonging to the plurality of consecutive bands, wherein the decoded image is decoded as an object; and encoding the image with the decoded image to which the offset is applied.

15 . The method according to claim 14 , further comprising:
applying a deblocking filter on a decoded image, wherein the deblocking filter is applied by the filter unit as an object, and applying the offset to the plurality of pixels, of the deblock filtered decoded image, of the plurality of consecutive bands.

16 . The method according to claim 15 , further comprising encoding the image for each of coding units divided using a quadtree segmentation.

17 . The method according to claim 16 , wherein the coding units are divided into prediction units and transform units.

Assignees

• Sony Corp

Inventors

• Maani Ehsan
• Tabatabai Ali J
• Xu Jun

Classifications

• H04N19/117 Primary

  Filters, e.g. for pre-processing or post-processing (sub-band filter banks H04N19/635) · CPC title

• H04N19/00 Primary

  Methods or arrangements for coding, decoding, compressing or decompressing digital video signals · CPC title

• H04N19/50

  using predictive coding (H04N19/61 takes precedence) · CPC title

• H04N19/14

  Coding unit complexity, e.g. amount of activity or edge presence estimation (H04N19/146 takes precedence) · CPC title

• H04N19/176 Primary

  the region being a block, e.g. a macroblock · CPC title