US 11,706,429 B2
Method and device for encoding and decoding image involving gradual refresh technique
Dong Gyu Sim, Seoul (KR); Han Sol Choi, Gyeonggi-do (KR); Jong Seok Lee, Seoul (KR); Sea Nae Park, Seoul (KR); Seung Wook Park, Gyeonggi-do (KR); and Wha Pyeong Lim, Gyeonggi-do (KR)
Assigned to Hyundai Motor Company, Seoul (KR); Kia Motors Corporation, Seoul (KR); and Kwangwoon University Industry-Academic Collaboration Foundation, Seoul (KR)
Appl. No. 17/278,453
Filed by Hyundai Motor Company, Seoul (KR); Kia Motors Corporation, Seoul (KR); and Kwangwoon University Industry-Academic Collaboration Foundation, Seoul (KR)
PCT Filed Mar. 12, 2020, PCT No. PCT/KR2020/003433
§ 371(c)(1), (2) Date Mar. 22, 2021,
PCT Pub. No. WO2020/184999, PCT Pub. Date Sep. 17, 2020.
Claims priority of application No. 10-2019-0028371 (KR), filed on Mar. 12, 2019; application No. 10-2019-0030334 (KR), filed on Mar. 18, 2019; and application No. 10-2019-0056985 (KR), filed on May 15, 2019.
Prior Publication US 2021/0368191 A1, Nov. 25, 2021
Int. Cl. H04N 19/44 (2014.01); H04N 19/105 (2014.01); H04N 19/159 (2014.01); H04N 19/176 (2014.01); H04N 19/46 (2014.01); H04N 19/82 (2014.01)
CPC H04N 19/44 (2014.11) [H04N 19/105 (2014.11); H04N 19/159 (2014.11); H04N 19/176 (2014.11); H04N 19/46 (2014.11); H04N 19/82 (2014.11)] 10 Claims
OG exemplary drawing
 
1. A video decoding method for decoding a sequence of pictures using gradual refresh, comprising:
decoding, from a header of the sequence in a bitstream, a flag indicating whether the gradual refresh is allowed;
decoding identification information for identifying a first picture to which the gradual refresh has been applied in the sequence, and determining a picture order count (POC) value of the first picture;
decoding group size information for identifying a group of pictures associated with the first picture to which the gradual refresh has been applied;
determining a POC value of a second picture corresponding to a last picture belonging to the group based on the group size information; and
determining the group of pictures associated with the first picture using the POC value of the first picture and the POC value of the second picture,
wherein, whether to display decoded pictures is determined based on POC values of the decoded pictures such that pictures having a POC value greater than or equal to the POC value of the first picture and less than the POC value of the second picture are not allowed to be displayed after being decoded,
wherein, the identification information indicates that the gradual refresh is not applied to the first picture in the sequence based on the flag indicating that the gradual refresh is not allowed,
wherein, the identification information is decoded from a header of the first picture,
wherein, when the identification information indicates that the first picture is to be subjected to the gradual refresh, the group size information is decoded from the header of the first picture,
wherein, when a block in a picture belonging to the group is inter-predicted, prediction using a reference block padded with a predefined value is allowed for the block,
wherein, the predefined value is derived from a bit depth of pixel values, and
wherein, the predefined value is equal to ½ of a maximum value expressed by the bit depth of the pixel values.