Signaling of deblocking filter parameters in video coding

Patent metadata

Field	Value
Publication number	US-9723331-B2
Application number	US-201615353367-A
Country	US
Kind code	B2
Filing date	Nov 16, 2016
Priority date	Jan 19, 2012
Publication date	Aug 1, 2017
Grant date	Aug 1, 2017

Abstract

This disclosure describes techniques for signaling deblocking filter parameters for a current slice of video data with reduced bitstream overhead. Deblocking filter parameters may be coded in one or more of a picture layer parameter set and a slice header. The techniques reduce a number of bits used to signal the deblocking filter parameters by coding a first syntax element that indicates whether deblocking filter parameters are present in both the picture layer parameter set and the slice header, and only coding a second syntax element in the slice header when both sets of deblocking filter parameters are present. Coding the second syntax element is eliminated when deblocking filter parameters are present in only one of the picture layer parameter set or the slice header. The second syntax element indicates which set of deblocking filter parameters to use to define a deblocking filter applied to a current slice.

First claim

What is claimed is:

1. A method of encoding video data, the method comprising:
encoding a picture layer syntax element in a picture layer parameter set, the picture layer syntax element indicating whether deblocking filter parameters are present in the picture layer parameter set;
when the picture layer syntax element indicates that deblocking filter parameters are present in the picture layer parameter set, encoding a slice layer syntax element in a slice header defined to indicate whether to use a first set of deblocking filter parameters included in the picture layer parameter set or a second set of deblocking filter parameters included in the slice header to define a deblocking filter applied to a current video slice; and
when the picture layer syntax element indicates that deblocking filter parameters are not present in both the picture layer parameter set and the slice header, encoding the slice header without including the slice layer syntax element.

2. The method of claim 1 , wherein the picture layer parameter set comprises one of a picture parameter set (PPS) or an adaptation parameter set (APS).

3. The method of claim 1 , wherein encoding the picture layer syntax element comprises encoding the picture layer syntax element in one of the picture layer parameter set or a sequence parameter set (SPS).

4. The method of claim 1 , further comprising, when the picture layer syntax element indicates that deblocking filter parameters are not present in both the picture layer parameter set and the slice header, defining the deblocking filter applied to the current video slice based on deblocking filter parameters present in one of the picture layer parameter set and the slice header.

5. The method of claim 1 , wherein encoding the picture layer syntax element comprises encoding an override enabled flag in the picture layer parameter set that indicates whether an override of the first set of deblocking filter parameters by the second set of deblocking filter parameters is enabled.

6. The method of claim 5 , wherein, when the override is enabled, encoding the slice layer syntax element comprises encoding an override flag in the slice header that indicates whether to use the first set of deblocking filter parameters from the picture layer parameter set or to override the first set of deblocking filter parameters with the second set of deblocking filter parameters included in the slice header to define the deblocking filter applied to the current video slice.

7. The method of claim 5 , wherein, when the override is not enabled, encoding the slice header comprises encoding the slice header without including an override flag in the slice header, further comprising defining the deblocking filter applied to the current video slice based on the first set of deblocking filter parameters included in the picture layer parameter set.

8. The method of claim 1 , wherein encoding the picture layer syntax element comprises encoding an inherit enabled flag that indicates whether the first set of deblocking filter parameters is present in the picture layer parameter set to be inherited by the slice header.

9. The method of claim 8 , wherein, when the first set of deblocking filter parameters is present to be inherited by the slice header, encoding the slice layer syntax element comprises encoding an inherit flag in the slice header that indicates whether to use the second set of deblocking filter parameters included in the slice header or to inherit the first set of deblocking filter parameters from the picture layer parameter set to define the deblocking filter applied to the current video slice.

10. The method of claim 8 , wherein, when the first set of deblocking filter parameters is not present to be inherited by the slice header, encoding the slice header comprises encoding the slice header without including an inherit flag in the slice header, further comprising defining the deblocking filter applied to the current video slice based on the second set of deblocking filter parameters included in the slice header.

11. The method of claim 1 , further comprising encoding a third syntax element defined to indicate that deblocking filter control syntax elements are present in the picture layer parameter set and the slice header prior to encoding the picture layer syntax element, wherein the picture layer syntax element and the slice layer syntax element comprise deblocking filter control syntax elements.

12. The method of claim 11 , wherein encoding the third syntax element comprises encoding a control present syntax element in one of the picture layer parameter set and a sequence parameter set (SPS).

13. The method of claim 1 , further comprising encoding a fourth syntax element defined to indicate that the deblocking filter is enabled for the current video slice.

14. The method of claim 13 , wherein encoding the fourth syntax element comprises encoding a deblocking filter enabled flag in a sequence parameter set (SPS) prior to encoding the picture layer syntax element.

15. A video encoding device comprising:
a memory that stores video data; and
one or more processors configured to encode a picture layer syntax element in a picture layer parameter set, the picture layer syntax element indicating whether deblocking filter parameters are present in both a picture layer parameter set and a slice header,
wherein the one or more processors are configured to, when the picture layer syntax element indicates that deblocking filter parameters are present in the picture layer parameter set, encode a slice layer syntax element in a slice header defined to indicate whether to use a first set of deblocking filter parameters included in the picture layer parameter set or a second set of deblocking filter parameters included in the slice header to define a deblocking filter applied to a current video slice, and
wherein the one or more processors are configured to, when the picture layer syntax element indicates that deblocking filter parameters are not present in both the picture layer parameter set and the slice header, encode the slice header without including the slice layer syntax element.

16. The video encoding device of claim 15 , wherein the picture layer parameter set comprises one of a picture parameter set (PPS) or an adaptation parameter set (APS).

17. The video encoding device of claim 15 , wherein the one or more processors are configured to encode the picture layer syntax element in one of the picture layer parameter set or a sequence parameter set (SPS).

18. The video encoding device of claim 15 , wherein the one or more processors are configured to, when the picture layer syntax element indicates that deblocking filter parameters are not present in both the picture layer parameter set and the slice header, define the deblocking filter applied to the current video slice based on deblocking filter parameters present in one of the picture layer parameter set and the slice header.

19. The video encoding device of claim 15 , wherein the one or more processors are configured to encode an override enabled flag in the picture layer parameter set that indicates whether an override of the first set of deblocking filter parameters by the second set of deblocking filter parameters is enabled.

20. The video encoding device of claim 19 , wherein the one or more processors are configured to, when the override is enabled, encode an override flag in the slice header that indicates whether to use the first set of deblocking filter parameters from the picture layer

Assignees

• Qualcomm Inc

Inventors

• Van Der Auwera Geert
• Wang Ye-Kui
• Karczewicz Marta

Classifications

• H04N19/172

  the region being a picture, frame or field · CPC title

• H04N19/176

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

• H04N19/86 Primary

  involving reduction of coding artifacts, e.g. of blockiness · CPC title

• H04N19/174

  the region being a slice, e.g. a line of blocks or a group of blocks · CPC title

• H04N19/159

  Prediction type, e.g. intra-frame, inter-frame or bidirectional frame prediction · CPC title