HIGH LEVEL SYNTAX FOR HEVC EXTENSIONS

1 - 20 . (canceled)

21 . A video processing method comprising:

receiving a video bitstream comprising a plurality of non-video coding layer (non-VCL) network abstraction layer (NAL) units;

determining whether to preserve a non-VCL NAL unit based on layer dependency associated with a current layer and an NAL unit header layer identifier associated with the non-VCL NAL unit; and

processing the non-VCL NAL unit based on the determination, wherein based on a determination to preserve the non-VCL NAL unit, the non-VCL NAL unit is included in a sub-bitstream, and based on a determination not to preserve the non-VCL NAL unit, the non-VCL NAL unit is removed.

22 . The video processing method of claim 21 , wherein the plurality of non-VCL NAL units comprise a plurality of picture parameter set (PPS) NAL units and a plurality of sequence parameter set (SPS) NAL units, and the non-VCL NAL unit is a PPS NAL unit or an SPS NAL unit.

23 . The video processing method of claim 21 , wherein determining whether to preserve the non-VCL NAL unit further comprises:

identifying one or more reference layers of the current layer based on the layer dependency associated with the current layer; and

determining to preserve the non-VCL NAL unit when the NAL unit header layer identifier associated with the NAL unit identifies a reference layer of the one or more reference layers of the current layer.

24 . The video processing method of claim 21 , wherein determining whether to preserve the non-VCL NAL unit further comprises:

identifying one or more reference layers of the current layer based on the layer dependency associated with the current layer; and

determining to preserve the non-VCL NAL unit on a condition that the NAL unit header layer identifier associated with the non-VCL NAL unit is zero, identifies the current layer, or identifies a reference layer of the one or more reference layers of the current layer.

25 . The video processing method of claim 1 , wherein determining whether to preserve the non-VCL NAL unit further comprises:

identifying one or more reference layers of the current layer based on the layer dependency associated with the current layer; and

determining to remove the non-VCL NAL unit on the condition that the NAL unit header layer identifier associated with the non-VCL NAL unit is not one of: zero, a value indicative of the current layer, or a value indicative of a reference layer of the one or more reference layers of the current layer.

26 . A device comprising:

a processor configured to:

receive a video bitstream comprising a plurality of non-video coding layer (non-VCL) network abstraction layer (NAL) units;

determine whether to preserve a non-VCL NAL unit based on layer dependency associated with a current layer and an NAL unit header layer identifier associated with the non-VCL NAL unit; and

process the non-VCL NAL unit based on the determination, wherein based on a determination to preserve the non-VCL NAL unit, the non-VCL NAL unit is included in a sub-bitstream, and based on a determination not to preserve the non-VCL NAL unit, the non-VCL NAL unit is removed.

27 . The device of claim 26 , wherein the plurality of non-VCL NAL units comprise a plurality of picture parameter set (PPS) NAL units and a plurality of sequence parameter set (SPS) NAL units, and the non-VCL NAL unit is a PPS NAL unit or an SPS NAL unit.

28 . The device of claim 26 , wherein the processor is further configured to:

identify one or more reference layers of the current layer based on the layer dependency associated with the current layer; and

determine to preserve the non-VCL NAL unit when the NAL unit header layer identifier associated with the non-VCL NAL unit identifies a reference layer of the one or more reference layers of the current layer.

29 . The device of claim 26 , wherein the processor is further configured to:

identify one or more reference layers of the current layer based on the layer dependency associated with the current layer; and

determine to preserve the non-VCL NAL unit on a condition that the NAL unit header layer identifier associated with the non-VCL NAL unit is zero, a value indicative of the current layer, or a value indicative of a reference layer of the one or more reference layers of the current layer.

30 . The device of claim 26 , wherein the processor is further configured to:

identify one or more reference layers of the current layer based on the layer dependency associated with the current layer; and

determine to remove the non-VCL NAL unit on the condition that the NAL unit header layer identifier associated with the non-VCL NAL unit is not one of: zero, a value indicative of the current layer, or a value indicative of a reference layer of the one or more reference layers of the current layer.

31 . A video coding device comprising:

a processor configured to:

identify a slice segment associated with a current layer;

identify a network abstraction layer (NAL) unit that comprises a parameter set applicable to the slice segment;

determine, based on layer dependency associated with the current layer and an NAL unit header layer identifier of the NAL unit, whether the slice segment can refer to the identified NAL unit; and

set a value for a reference parameter set identifier associated with the slice segment based on the determining.

32 . The video coding device of claim 31 , wherein the NAL unit is a picture parameter set (PPS) NAL unit.

33 . The video coding device of claim 31 , wherein processor is further configured to:

identify one or more reference layers of the current layer based on the layer dependency associated with the current layer;

determine that the slice segment can refer to the NAL unit when the NAL unit header layer identifier of the NAL unit identifies a reference layer of the one or more reference layers of the current layer; and

set the value for the reference parameter set identifier associated with the slice segment to a value indicative of the NAL unit.

34 . The video coding device of claim 31 , wherein processor is further configured to:

identify one or more reference layers of the current layer based on the layer dependency associated with the current layer;

determine that the slice segment can refer to the NAL unit when the NAL unit header layer identifier of the NAL unit is zero, a value indicative of the current layer, or a value indicative of a reference layer of the current layer; and

set the value for the reference parameter set identifier associated with the slice segment to a value indicative of the NAL unit.

35 . The video coding device of claim 31 , wherein the NAL unit is a picture parameter set (PPS) NAL unit, and the processor is further configured to:

identify a sequence parameter set (SPS) NAL unit that comprises an SPS applicable to the PPS NAL unit;

determine, based on the layer dependency associated with the current layer and an NAL unit header layer identifier of the SPS NAL unit, whether the PPS NAL unit can refer to the SPS NAL unit, wherein the processor is configured to determine that the PPS NAL unit can refer to the SPS NAL unit when the NAL unit header layer identifier of the SPS NAL unit is zero, a value indicative of the current layer, or a value indicative of a reference layer of the current layer; and

set a value for a reference parameter set identifier associated with the PPS NAL unit to a value indicative of the SPS NAL unit.