Output of prior pictures for pictures starting a new coded video sequence in video coding
A decoding device and a method of decoding implemented by a video decoder are disclosed. The decoding method includes receiving a coded video bitstream, where the coded video bitstream contains a gradual decoding refresh (GDR) picture and a first flag having a value; setting a value of a second flag equal to the value of the first flag, where the value of the second flag derived for the video decoder under test is applied for a hypothetical reference decoder (HRD); and when the value of the second flag is equal to one, emptying all picture storage buffers in a decoded picture buffer (DPB) without output of pictures contained in the DPB and setting a DPB fullness parameter to zero.
1. A method of decoding implemented by a video decoder, comprising:
receiving a coded video bitstream, wherein the coded video bitstream contains a gradual decoding refresh (GDR) picture and a first flag having a value;
setting a value of a second flag equal to the value of the first flag, wherein the value of the second flag derived for the video decoder under test is applied for a hypothetical reference decoder (HRD); and
when the value of the second flag is equal to one, emptying all picture storage buffers in a decoded picture buffer (DPB) without output of pictures contained in the DPB and setting a DPB fullness parameter to zero.
2. The method of claim 1 , wherein the GDR picture is not a first picture of the coded video bitstream.
3. The method of claim 1 , wherein the GDR picture is disposed in a video coding layer (VCL) network abstraction layer (NAL) unit having a GDR NAL unit type (GDR_NUT).
4. The method of claim 1 , further comprising setting the DPB fullness parameter to zero when the value of the first flag is set to one.
5. The method of claim 1 , wherein the first flag is designated as no_output_of_prior_pics_flag and the second flag is designated as NoOutputOfPriorPicsFlag.
6. The method of claim 1 , wherein the DPB is emptied after the GDR picture has been decoded.
7. The method of claim 1 , further comprising displaying an image generated based on a current picture.
8. A decoding device, comprising:
a memory storing instructions; and
one or more processors coupled to the memory, wherein the one or more processors are configured to execute the instructions to cause the decoding device to:
receive a coded video bitstream, wherein the coded video bitstream contains a gradual decoding refresh (GDR) picture and a first flag having a value;
set a value of a second flag equal to the value of the first flag, wherein the value of the second flag derived for the decoding device under test is applied for a hypothetical reference decoder (HRD); and
when the value of the second flag is equal to one, emptying all picture storage buffers in a decoded picture buffer (DPB) without output of pictures contained in the DPB and setting a DPB fullness parameter to zero.
9. The decoding device of claim 8 , wherein the GDR picture is not a first picture of the coded video bitstream.
10. The decoding device of claim 8 , wherein the first flag is designated as no_output_of_prior_pics_flag, and wherein the second flag is designated as NoOutputOfPriorPicsFlag.
11. The decoding device of claim 8 , further comprising a display configured to display an image as generated based on a current picture.