Methods and apparatuses for signaling of syntax elements in video coding
A method for video coding is provided. The method includes: setting, by an encoder, a first syntax element in a picture parameter set (PPS) specifying whether a picture corresponding to the PPS comprises more than one network abstraction layer (NAL) units and whether the more than one NAL units have a same NAL unit type; setting, by the encoder, a second syntax element in a picture header (PH) specifying whether the picture corresponding to the PH is an intra random access point (IRAP) picture or a gradual decoding refresh (GDR) picture, wherein a value of the first syntax element is set based on a value of the second syntax element being 1; and forming, by the encoder, a bitstream with the first syntax element and the second syntax element.
1 . A method for video coding, comprising:
setting, by an encoder, a first syntax element in a picture parameter set (PPS) specifying whether a picture corresponding to the PPS comprises more than one network abstraction layer (NAL) units and whether the more than one NAL units have a same NAL unit type;
setting, by the encoder, a second syntax element in a picture header (PH) specifying whether the picture corresponding to the PH is an intra random access point (IRAP) picture or a gradual decoding refresh (GDR) picture,
wherein a value of the first syntax element is set based on a value of the second syntax element being 1; and
forming, by the encoder, a bitstream with the first syntax element and the second syntax element.
2 . The method of claim 1 , wherein the value of the first syntax element being equal to 1 specifies that each picture corresponding to the PPS comprises more than one video coding layer (VCL) NAL units and the more than one VCL NAL units do not have a same NAL unit type, and the value of the first syntax element being equal to 0 specifies that each picture corresponding to the PPS comprises more than one VCL NAL units and the more than one VCL NAL units have a same NAL unit type; and
wherein the value of the second syntax element being equal to 1 specifies that the picture corresponding to the PH is an IRAP picture or a GDR picture, and the value of the second syntax element being equal to 0 specifies that the picture corresponding to the PH is not a GDR picture.
3 . The method of claim 1 , wherein the value of the first syntax element is set to be 0 based on the value of the second syntax element specifying that the picture is an IRAP picture or a GDR picture.
4 . The method of claim 1 , wherein the value of the first syntax element is set to be 1 based on that the picture is neither an IRAP picture nor a GDR picture.
5 . An apparatus for video coding, comprising:
one or more processors; and
a memory configured to store instructions executable by the one or more processors; wherein the one or more processors, upon execution of the instructions, are configured to perform a method comprising following steps:
setting, by an encoder, a first syntax element in a picture parameter set (PPS) specifying whether a picture corresponding to the PPS comprises more than one network abstraction layer (NAL) units and whether the more than one NAL units have a same NAL unit type;
setting, by the encoder, a second syntax element in a picture header (PH) specifying whether the picture corresponding to the PH is an intra random access point (IRAP) picture or a gradual decoding refresh (GDR) picture,
wherein a value of the first syntax element is set based on a value of the second syntax element being 1; and
forming, by the encoder, a bitstream with the first syntax element and the second syntax element.
6 . The apparatus of claim 5 , wherein the value of the first syntax element being equal to 1 specifies that each picture corresponding to the PPS comprises more than one video coding layer (VCL) NAL units and the more than one VCL NAL units do not have a same NAL unit type, and the value of the first syntax element being equal to 0 specifies that each picture corresponding to the PPS comprises more than one VCL NAL units and the more than one VCL NAL units have a same NAL unit type; and
wherein the value of the second syntax element being equal to 1 specifies that the picture corresponding to the PH is an IRAP picture or a GDR picture, and the value of the second syntax element being equal to 0 specifies that the picture corresponding to the PH is not a GDR picture.
7 . The apparatus of claim 5 , wherein the value of the first syntax element is set to be 0 based on the value of the second syntax element specifying that the picture is an IRAP picture or a GDR picture.
8 . The apparatus of claim 5 , wherein the value of the first syntax element is set to be 1 based on that the picture is neither an IRAP picture nor a GDR picture.
9 . A method for storing a bitstream, comprising:
performing the method according to claim 1 to generate a bitstream; and
storing the bitstream.
10 . The method of claim 9 , wherein the value of the first syntax element being equal to 1 specifies that each picture corresponding to the PPS comprises more than one video coding layer (VCL) NAL units and the more than one VCL NAL units do not have a same NAL unit type, and the value of the first syntax element being equal to 0 specifies that each picture corresponding to the PPS comprises more than one VCL NAL units and the more than one VCL NAL units have a same NAL unit type; and
wherein the value of the second syntax element being equal to 1 specifies that the picture corresponding to the PH is an IRAP picture or a GDR picture, and the value of the second syntax element being equal to 0 specifies that the picture corresponding to the PH is not a GDR picture.
11 . The method of claim 9 , wherein the value of the first syntax element is set to be 0 based on the value of the second syntax element specifying that the picture is an IRAP picture or a GDR picture.
12 . The method of claim 9 , wherein the value of the first syntax element is set to be 1 based on that the picture is neither an IRAP picture nor a GDR picture.