NAL Unit Header

Abstract

Disclosed are techniques for scalable, multiview, and multiple descriptive video coding using an improved Network Adaptation Layer (NAL) unit header. A NAL unit header can include a layer-id that can be a reference into a table of layer descriptions, which specify the properties of the layer. The improved NAL unit header can further include fields for reference picture management and to identify temproal layers.

1 . A method for video decoding, comprising:
 receiving a table of layer descriptions comprising at least one layer description identified by a first layer_id;   receiving a NAL unit header comprising a second layer_id; and   determining at least one property of the layer that the NAL unit belongs to by matching the second layer_id with the first layer_id.   
     
     
         2 . The method of  claim 1 , wherein the at least one property comprises at least one of: a dependency_id, a quality_id, a temporal_id, a view_id, a depth_map_flag, and a dependent_flag. 
     
     
         3 . The method of  claim 1 , wherein the NAL unit header further comprises a temporal_id. 
     
     
         4 . The method of  claim 3 , wherein the temporal_id identifies a temporal sub-layer of a layer identified by the layer_id. 
     
     
         5 . The method of  claim 1 , wherein the table of layer descriptions is part of a dependency parameter set. 
     
     
         6 . The method of  claim 2 , wherein the depth_map_flag indicates that the first layer the NAL unit belongs to is a depth map, and is associated with a second layer identified by having the same view_id as the first layer. 
     
     
         7 . The method of  claim 1 , wherein a predefined value for the second layer_id identifies the presence of extension data. 
     
     
         8 . The method of  claim 1 , wherein the first layer_id is an indication of a position of the layer in a layer hierarchy. 
     
     
         9 . The method of  claim 1 , wherein the NAL unit header further comprises at least one of: a store_ref_base_pic_flag and a use_ref_base_pic_flag. 
     
     
         10 . The method of  claim 1 , wherein the NAL unit header is a slice NAL unit header, and the slice header of the slice carried in the NAL unit comprises at least one of a store_ref_base_pic_flag, and use_ref_base_pic_flag. 
     
     
         11 . A method for video encoding, comprising:
 determining a layer structure comprising at least one layer having a first layer_id;   encoding a representation of the layer structure in a table of layers, the table of layers comprising layer descriptions comprising at least one property of the layer; and   encoding at least one NAL unit comprising a second layer_id;   wherein the second layer_id is the same as the first layer_id.   
     
     
         12 . The method of  claim 11 , wherein the at least one property comprises at least one of: a dependency_id, a quality_id, a temporal_id, a view id, a depth_map_flag, and a dependent_flag. 
     
     
         13 . The method of  claim 11 , wherein the NAL unit header further comprises a temporal_id. 
     
     
         14 . The method of  claim 13 , wherein the temporal_id identifies a temporal sub-layer of a layer identified by the layer_id. 
     
     
         15 . The method of  claim 11 , wherein the table of layer descriptions is part of a dependency parameter set. 
     
     
         16 . The method of  claim 12 , wherein the depth_map_flag indicates that the first layer the NAL unit belongs to is a depth map, and is associated with a second layer identified by having the same view_id as the first layer. 
     
     
         17 . The method of  claim 11 , wherein a predefined value for the second layer_id identifies the presence of extension data. 
     
     
         18 . The method of  claim 11 , wherein the first layer_id is an indication of a position of the layer in a layer hierarchy. 
     
     
         19 . The method of  claim 11 , wherein the NAL unit header further comprises at least one of: a store_ref_base_pic_flag and a use_ref_base_pic_flag. 
     
     
         20 . The method of  claim 11 , wherein the NAL unit header is a slice NAL unit header, and the slice header of the slice carried in the NAL unit comprises at least one of a store_ref_base_pic_flag, and use_ref_base_pic_flag. 
     
     
         21 . A method for removing NAL units from a scalable bitstream, comprising:
 receiving and decoding a table of layer descriptions comprising at least one layer description comprising at least one first layer_id;   receiving a slice NAL unit comprising a NAL unit header comprising a second layer_id;   removing the slice NAL unit only if the second layer_id identifies it as belonging to a layer to be removed.   
     
     
         22 . The method of  claim 21 , wherein, the table of layer descriptions comprises a plurality of layer descriptions each having a layer_id, wherein no first layer described by a first layer description is depending on a second layer described by a second layer description, and wherein the layer_id of the first layer description is numerically lower than the layer_id of the second layer description. 
     
     
         23 . The method of  claim 21 , wherein, the table of layer descriptions comprises a plurality of layer descriptions each having a layer_id, wherein no first layer described by a first layer description is depending on a second layer described by a second layer description, and wherein the layer_id of the first layer description is numerically higher than the layer_id of the second layer description. 
     
     
         24 . The method of  claim 22 , further comprising:
 after the removing of at least one NAL unit with a first layer_id, removing at least one NAL unit of a layer with a second layer_id; and   wherein the second layer_id is numerically lower than the first layer_id.   
     
     
         25 . The method of  claim 23 , further comprising:
 after the removing of at least one NAL unit with a first layer_id, removing at least one NAL unit of a layer with a second layer_id; and   wherein the second layer_id is numerically higher than the first layer_id.   
     
     
         26 . Non-transitory computer readable media comprising a set of instructions to perform the methods in one of  claims 1  to  25 .