US 12,382,079 B2
Techniques for random access point indication and picture output in coded video stream
Byeongdoo Choi, Palo Alto, CA (US); Stephan Wenger, Palo Alto, CA (US); and Shan Liu, Palo Alto, CA (US)
Assigned to TENCENT AMERICA LLC, Palo Alto, CA (US)
Filed by TENCENT AMERICA LLC, Palo Alto, CA (US)
Filed on Feb. 16, 2024, as Appl. No. 18/443,861.
Application 18/443,861 is a continuation of application No. 17/965,203, filed on Oct. 13, 2022, granted, now 11,956,457.
Application 17/965,203 is a continuation of application No. 17/320,764, filed on May 14, 2021, granted, now 11,558,630, issued on Jan. 17, 2023.
Claims priority of provisional application 63/037,903, filed on Jun. 11, 2020.
Claims priority of provisional application 63/036,335, filed on Jun. 8, 2020.
Claims priority of provisional application 63/035,274, filed on Jun. 5, 2020.
Claims priority of provisional application 63/027,826, filed on May 20, 2020.
Prior Publication US 2024/0187630 A1, Jun. 6, 2024
This patent is subject to a terminal disclaimer.
Int. Cl. H04N 19/46 (2014.01); H04N 19/105 (2014.01); H04N 19/159 (2014.01); H04N 19/169 (2014.01); H04N 19/172 (2014.01)
CPC H04N 19/46 (2014.11) [H04N 19/105 (2014.11); H04N 19/159 (2014.11); H04N 19/172 (2014.11); H04N 19/188 (2014.11)] 20 Claims
OG exemplary drawing
 
1. A method of video decoding performed by at least one processor, the method comprising:
receiving a coded video stream that includes an access unit, including a picture;
determining whether a first flag, in an access unit delimiter of the coded video stream, indicates that the access unit includes either or neither one from among an intra random access point (IRAP) picture and a gradual decoding refresh (GDR) picture;
determining whether a second flag, in a picture header of the coded video stream, indicates that the picture is the IRAP picture; and
decoding the picture, as a current picture, based on the first flag and the second flag,
wherein a value of the first flag and a value of the second flag are aligned, and
wherein the decoding comprises:
constructing a reference picture list;
generating an unavailable reference picture in the reference picture list; and
checking bitstream conformance, for reference pictures in the reference picture list, that the following constraints apply:
a number of entries that are indicated to be in the reference picture list is not less than a number of active entries that are indicated to be in the reference picture list,
each picture referred to by an active entry in the reference picture list is present in a decoded picture buffer (DPB) and has a temporal identifier value less than or equal to a temporal identifier value of the current picture, and
each picture referred to by an entry in the reference picture list is not the current picture and is indicated by a picture header flag to potentially be a reference picture.