Signaling non-scalable-nested hypothetical reference video decoder information

1. A method of processing video data, comprising:

performing a conversion between a video and a bitstream of the video,

wherein the bitstream comprises one or more output layer sets comprising one or more video layers according to a format rule,

wherein the format rule specifies that a value of layer identifier for a supplemental enhancement information (SEI) network abstraction layer (NAL) unit that includes a non-scalable-nested SEI message is not constrained, and

wherein the format rule further specifies that a particular payload type value corresponding to subpicture level information is disallowed from a list that includes allowable SEI payload type values, wherein the particular payload type value is 203.

2. The method of claim 1 , wherein the non-scalable-nested SEI message is an SEI message that is not contained in a scalable nesting SEI message.

3. The method of claim 1 , wherein the format rule further specifies that a non-scalable-nested SEI message that includes information regarding hypothetical reference decoder (HRD) is applicable to all output layer sets that include video layers as the bitstream.

4. The method of claim 3 , wherein the format rule further specifies that a non-scalable-nested hypothetical reference decoder (HRD)-related supplemental enhancement information (SEI) message is omitted responsive to a condition that there does not exist an output layer set that includes the video layers as the bitstream.

5. The method of claim 4 , wherein the non-scalable-nested SEI message is a buffering period (BP) SEI message, a picture timing (PT) SEI message, a decoding unit information (DUI) SEI message, or a subpicture level information (SLI) SEI message.

6. The method of claim 5 , wherein the non-scalable-nested SEI message has a payload type that is equal to 0, 1, 130 or 203.

7. The method of claim 1 , wherein the allowable SEI payload type values include filler payload, film grain characteristics, frame packing arrangement, parameter sets inclusion indication, mastering display color volume, content light level information, dependent rap indication, alternative transfer characteristics, ambient viewing environment, content color volume, equirectangular projection, generalized cube map projection, sphere rotation, region-wise packing, omni viewport, frame field information and sample aspect ratio information.

8. The method of claim 7 , wherein the allowable SEI payload type values include 3, 19, 45, 129, 137, 144, 145, 147 to 150, 153 to 156, 168, and 204.

9. The method of claim 7 , wherein the SEI messages corresponding the allowable SEI payload type values of the list infer constraints on NAL unit header of the SEI NAL unit on the basis of the NAL unit header of associated video coding layer (VCL) NAL unit when non-scalable-nested.

10. The method of claim 1 , wherein the conversion includes encoding the video into the bitstream.

11. The method of claim 1 , wherein the conversion includes decoding the video from the bitstream.

12. An apparatus for processing video data comprising a processor and a non-transitory memory with instructions thereon, wherein the instructions upon execution by the processor, cause the processor to:

perform a conversion between a video and a bitstream of the video,

wherein the bitstream comprises one or more output layer sets comprising one or more video layers according to a format rule,

wherein the format rule specifies that a value of layer identifier for a supplemental enhancement information (SEI) network abstraction layer (NAL) unit that includes a non-scalable-nested SEI message is not constrained, and

wherein the format rule further specifies that a particular payload type value corresponding to subpicture level information is disallowed from a list that includes allowable SEI payload type values, wherein the particular payload type value is 203.

13. The apparatus of claim 12 , wherein the non-scalable-nested SEI message is an SEI message that is not contained in a scalable nesting SEI message.

14. The apparatus of claim 12 , wherein the format rule further specifies that the format rule further specifies that a non-scalable-nested SEI message that includes information regarding hypothetical reference decoder (HRD) is applicable to all output layer sets that include video layers as the bitstream,

wherein the format rule further specifies that a non-scalable-nested hypothetical reference decoder (HRD)-related supplemental enhancement information (SEI) message is omitted responsive to a condition that there does not exist an output layer set that includes the video layers as the bitstream,

wherein the non-scalable-nested SEI message is a buffering period (BP) SEI message, a picture timing (PT) SEI message, a decoding unit information (DUI) SEI message, or a subpicture level information (SLI) SEI message,

wherein the non-scalable-nested SEI message has a payload type that is equal to 0, 1, 130 or 203, and

wherein the allowable SEI payload type values include filler payload, film grain characteristics, frame packing arrangement, parameter sets inclusion indication, mastering display color volume, content light level information, dependent rap indication, alternative transfer characteristics, ambient viewing environment, content color volume, equirectangular projection, generalized cube map projection, sphere rotation, region-wise packing, omni viewport, frame field information and sample aspect ratio information.

15. A non-transitory computer-readable storage medium storing instructions that cause a processor to:

perform a conversion between a video and a bitstream of the video,

wherein the bitstream comprises one or more output layer sets comprising one or more video layers according to a format rule,

wherein the format rule specifies that a value of layer identifier for a supplemental enhancement information (SEI) network abstraction layer (NAL) unit that includes a non-scalable-nested SEI message is not constrained, and

wherein the format rule further specifies that a particular payload type value corresponding to subpicture level information is disallowed from a list that includes allowable SEI payload type values, wherein the particular payload type value is 203.

16. The non-transitory computer-readable storage medium of claim 15 , wherein the non-scalable-nested SEI message is an SEI message that is not contained in a scalable nesting SEI message,

wherein the format rule further specifies that a non-scalable-nested SEI message that includes information regarding hypothetical reference decoder (HRD) is applicable to all output layer sets that include video layers as the bitstream,

wherein the format rule further specifies that a non-scalable-nested hypothetical reference decoder (HRD)-related supplemental enhancement information (SEI) message is omitted responsive to a condition that there does not exist an output layer set that includes the video layers as the bitstream,

wherein the non-scalable-nested SEI message is a buffering period (BP) SEI message, a picture timing (PT) SEI message, a decoding unit information (DUI) SEI message, or a subpicture level information (SLI) SEI message,

wherein the non-scalable-nested SEI message has a payload type that is equal to 0, 1, 130 or 203,

wherein the format rule further specifies that a particular payload type value corresponding to subpicture level information is disallowed from a list that includes allowable supplemental enhancement information (SEI) payload type values,

wherein the particular payload type value is 203, and

wherein the allowable SEI payload type values include filler payload, film grain characteristics, frame packing arrangement, parameter sets inclusion indication, mastering display color volume, content light level information, dependent rap indication, alternative transfer characteristics, ambient viewing environment, content color volume, equirectangular projection, generalized cube map projection, sphere rotation, region-wise packing, omni viewport, frame field information and sample aspect ratio information.

17. A non-transitory computer-readable recording medium storing a bitstream of a video which is generated by a method performed by a video processing apparatus, wherein the method comprises:

generating the bitstream of the video,

wherein the bitstream comprises one or more output layer sets comprising one or more video layers according to a format rule,

wherein the format rule specifies that a value of layer identifier for a supplemental enhancement information (SEI) network abstraction layer (NAL) unit that includes a non-scalable-nested SEI message is not constrained, and

wherein the format rule further specifies that a particular payload type value corresponding to subpicture level information is disallowed from a list that includes allowable SEI payload type values, wherein the particular payload type value is 203.

18. The non-transitory computer-readable recording medium of claim 17 , wherein the non-scalable-nested SEI message is an SEI message that is not contained in a scalable nesting SEI message,

wherein the format rule further specifies that a non-scalable-nested SEI message that includes information regarding hypothetical reference decoder (HRD) is applicable to all output layer sets that include video layers as the bitstream,

wherein the format rule further specifies that a non-scalable-nested hypothetical reference decoder (HRD)-related supplemental enhancement information (SEI) message is omitted responsive to a condition that there does not exist an output layer set that includes the video layers as the bitstream,

wherein the non-scalable-nested SEI message is a buffering period (BP) SEI message, a picture timing (PT) SEI message, a decoding unit information (DUI) SEI message, or a subpicture level information (SLI) SEI message,

wherein the non-scalable-nested SEI message has a payload type that is equal to 0, 1, 130 or 203, and

wherein the allowable SEI payload type values include filler payload, film grain characteristics, frame packing arrangement, parameter sets inclusion indication, mastering display color volume, content light level information, dependent rap indication, alternative transfer characteristics, ambient viewing environment, content color volume, equirectangular projection, generalized cube map projection, sphere rotation, region-wise packing, omni viewport, frame field information and sample aspect ratio information.

19. The apparatus of claim 12 , wherein the allowable SEI payload type values include 3, 19, 45, 129, 137, 144, 145, 147 to 150, 153 to 156, 168, and 204.

20. The apparatus of claim 12 , wherein the SEI messages corresponding the allowable SEI payload type values of the list infer constraints on NAL unit header of the SEI NAL unit on the basis of the NAL unit header of associated video coding layer (VCL) NAL unit when non-scalable-nested.