US 12,425,579 B2
Method, an apparatus and a computer program product for implementing gradual decoding refresh
Miska Matias Hannuksela, Tampere (FI)
Assigned to Nokia Technologies Oy, Espoo (FI)
Filed by Nokia Technologies Oy, Espoo (FI)
Filed on Jun. 27, 2023, as Appl. No. 18/342,023.
Prior Publication US 2024/0007619 A1, Jan. 4, 2024
Int. Cl. H04N 19/107 (2014.01); H04N 19/11 (2014.01); H04N 19/136 (2014.01); H04N 19/169 (2014.01); H04N 19/172 (2014.01); H04N 19/174 (2014.01); H04N 19/33 (2014.01); H04N 19/85 (2014.01)
CPC H04N 19/107 (2014.11) [H04N 19/11 (2014.11); H04N 19/136 (2014.11); H04N 19/172 (2014.11); H04N 19/174 (2014.11); H04N 19/188 (2014.11); H04N 19/33 (2014.11); H04N 19/85 (2014.11)] 15 Claims
OG exemplary drawing
 
1. An apparatus comprising:
at least one processor; and
at least one memory including computer program code;
wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus at least to:
receive an encoded video bitstream comprising a gradual decoding refresh picture and recovering pictures following the gradual decoding refresh picture in decoding order;
decode information that a slice-based gradual decoding refresh is in use, wherein each of the gradual decoding refresh picture and the recovering pictures comprises a first set of slices comprising a clean area and a second set of slices comprising rest of the picture; relabel the gradual decoding refresh picture as an intra-coded random access point picture in a modified bitstream;
include only the first set of slices of the gradual decoding refresh picture and the recovering pictures into the modified bitstream;
decode information on a picture width and a picture height of each of the gradual decoding refresh picture and the recovering pictures;
modify the picture width and the picture height to exclude the second set of slices;
include the modified information on the picture width and the picture height to the modified bitstream;
decode information on scaling window offsets relative to the decoded picture width and picture height of each of the gradual decoding refresh picture and the recovering pictures;
derive a scaling window from the scaling window offsets of each of the gradual decoding refresh picture and the recovering pictures;
modify the scaling window offsets of each of the gradual decoding refresh picture to be relative to the modified picture width and height so that the scaling window derived from the modified scaling window offsets remains unchanged in each of the gradual decoding refresh picture and the recovering pictures; and
include the modified information on the scaling window offsets to the modified bitstream.