Granted Patent B2

US 12,238,336 · App. 17/470,783 · Granted Feb 25, 2025

Inventors: Fnu Hendry (San Diego, CA); Ye-Kui Wang (San Diego, CA); Jianle Chen (San Diego, CA)

Assignee: Huawei Technologies Co., Ltd.

H04N19/70H04N19/107H04N19/14H04N19/162H04N19/172H04N19/174H04N19/188H04N19/1883H04N19/30H04N19/46

Abstract

Claims (25)

1. A method implemented by a decoder, the method comprising:

receiving a bitstream comprising a coded video sequence (CVS) and a gradual decoding refresh (GDR) flag corresponding to the CVS, wherein a value of the GDR flag is one (1) when a GDR picture is enabled in the CVS, wherein the GDR picture is associated with a GDR network abstract layer (NAL) unit type (GDR-NUT) and has a temporal identifier (TemporalID) equal to zero, wherein the bitstream further comprises a header including a syntax element indicating a picture order count of recovery point picture for the GDR picture, and wherein when the GDR picture is a first picture in the bitstream in decoding order or the first picture that follows an end of sequence (EOS) NAL unit in decoding order, a flag is set to one to prevent output of incorrect pictures;

determining whether the GDR picture is enabled for the CVS based on the value of the GDR flag; and

decoding the CVS based on the GDR flag.

2. The method of claim 1 , wherein the GDR flag is included in a sequence parameter set in the bitstream.

3. The method of claim 1 , wherein the GDR flag is designated as gdr_enabled_flag.

4. The method of claim 1 , wherein the GDR flag is configured to be set to a second value when the GDR picture is not enabled in the CVS.

5. The method of claim 4 , wherein the second value of the GDR flag is zero (0).

6. A method of encoding a video bitstream implemented by a video encoder, the method comprising:

encoding a gradual decoder refresh (GDR) picture in a coded video sequence (CVS) of the video bitstream, wherein the GDR picture is associated with a GDR network abstract layer (NAL) unit type (GDR-NUT) and has a temporal identifier (TemporalID) equal to zero;

setting a GDR flag to a first value to indicate that the GDR picture is present in the CVS of the video bitstream, wherein the first value of the GDR flag is one (1) when the GDR is enabled in the CVS, and wherein when the GDR picture is a first picture in the bitstream in decoding order or the first picture that follows an end of sequence (EOS) NAL unit in decoding order, a flag is set to one to prevent output of incorrect pictures; and

storing the video bitstream for transmission toward a video decoder, wherein the video bitstream further comprises a header including a syntax element indicating a picture order count of recovery point picture for the GDR picture.

7. The method of claim 6 , wherein the GDR flag is encoded in a sequence parameter set of the video bitstream.

8. The method of claim 6 , wherein the GDR flag is designated gdr_enabled_flag.

9. The method of claim 6 , wherein the GDR flag is configured to be set to a second value when the GDR picture is not present in the CVS of the video bitstream.

10. The method of claim 9 , wherein the second value of the GDR flag is zero (0).

11. A decoder comprising:

a receiver configured to receive a bitstream comprising a coded video sequence (CVS) and a gradual decoding refresh (GDR) flag corresponding to the CVS, wherein a value of the GDR flag is one (1) when a GDR picture is enabled in the CVS, wherein the GDR picture is associated with a GDR network abstract layer (NAL) unit type (GDR-NUT) and has a temporal identifier (TemporalID) equal to zero, and wherein the bitstream further comprises a header including a syntax element indicating a picture order count of recovery point picture for the GDR picture, and wherein when the GDR picture is a first picture in the bitstream in decoding order or the first picture that follows an end of sequence (EOS) NAL unit in decoding order, a flag is set to one to prevent output of incorrect pictures;

a processor coupled to the receiver and configured to:

determine whether the GDR picture is enabled for the CVS based on the value of the GDR flag; and

decode the CVS based on the GDR flag.

12. The decoder of claim 11 , wherein the GDR flag is included in a sequence parameter set in the bitstream.

13. The decoder of claim 11 , wherein the GDR flag is designated as gdr_enabled_flag.

14. The decoder of claim 11 , wherein the GDR flag is configured to be set to a second value when the GDR picture is not enabled in the CVS.

15. The decoder of claim 14 , wherein the second value of the GDR flag is zero (0).

Assignments (1)

Continuity (4)

References Cited (33)