Signaling scalability information in a parameter set

1. A method for decoding a coded video sequence comprising:

(a) receiving a video parameter set syntax that includes information applicable to a plurality of layers of said coded video sequence where said plurality of layers includes a base layer and at least one additional layer, and said video parameter set includes temporal scalability information including a maximum number of said at least one additional layer;

(b) receiving a video parameter set extension syntax that includes information applicable to said at least one additional layer that associates each of said at least one additional layer with scalability parameters and inter-layer dependencies;

(c) wherein said inter-layer dependencies indicate which of said at least one additional layer is used as one or more reference layers for inter-layer prediction;

(d) wherein said scalability parameters indicate a number and a type of scalability dimensions present in said coded video sequence for each of said at least one additional layer;

(e) wherein said scalability parameters are further characterized by a scalability mask including a pattern of 0 and 1 bits with each bit corresponding to a scalability dimension;

(f) wherein said scalability parameters are further characterized by said scalability mask related to a Number Scalability Types for each layer as the summation of the bits of said scalability mask for the corresponding layer, where said Number Scalability Types is used as maximum for a loop assigning values to a Dimension Identification of a first index and a second index where said first index signals one of said at least one additional layer and said second index signals a scalability dimension of said one of said at least one additional layer.

2. The method of claim 1 wherein said video parameter set extension syntax includes a while(!byte_aligned( )) syntax element indicating byte alignment.

3. The method of claim 1 wherein said video parameter set extension syntax includes a vps_extension_byte_alignment_reserved_one bit that is set to 1.

4. The method of claim 1 wherein said video parameter set extension syntax includes an avc_base_layer_flag specifying whether said base layer conforms to ITU-T H.264 specification.

5. The method of claim 1 wherein said video parameter set extension syntax includes said scalability mask that a said bit equal to 1 indicates the presence of a scalability dimension and a said bit equal to 0 indicates that non-presence of a scalability dimension.

6. The method of claim 1 wherein said Number Scalability Types is equal to the sum of the number of bits in said scalability mask having a value of 1.

7. The method of claim 1 wherein said Dimension Identification is derived based upon said maximum number of said at least one additional layer and said scalability mask.

8. The method of claim 1 wherein said video parameter set extension syntax includes the following syntax:

vps_extension( ) {

while( !byte_aligned( ) )

vps_extension_byte_alignment_reserved_one_bit

avc_base_layer_flag

scalability_mask[ i ]

for( j = 0; j <NumScalabilityTypes; j++ )

dimension_id_len_minus1[ j ]

vps_nuh_layer_id_present_flag

for( i = 1; i <= vps_max_layers_minus1; i++ ) {

if( vps_nuh_layer_id_present_flag )

layer_id_in_nuh[ i ]

for( j = 0; j < NumScalabilityTypes; j++ )

dimension_id[ i ][ j ]

}.

9. The method of claim 1 wherein said Dimension Identification of said video parameter set extension syntax is based upon a flag bit of a scalability mask.

10. The method of claim 1 wherein said Dimension Identification of said video parameter set extension syntax is based upon said scalability mask and a mapping of said scalability parameters.

11. The method of claim 1 wherein a scalability identifier is derived based upon said scalability mask and said Dimension Identification.