Cluster-based dependency signaling
The signalization of the inter-layer dependencies between layers of a multi-layered data stream is described. A good compromise between a too intensive restriction of the potential diversity of inter-layer dependencies on the one hand and a too complex signaling of the inter-layer dependencies on the other hand has been found by describing the inter-layer dependencies by way of a first inter-dependency syntax structure indicating inter-dependencies between pairs of different values representable by a base layer-ID and a second inter-dependency syntax structure indicating inter-dependencies between pairs of different values representable by an extension layer-ID, the base layer ID and extension layer ID indexing the layers the portions of the multi-layer data stream are associated with. In accordance with this concept, emphasis may be shifted between increased diversity of the signalizable inter-layer dependencies on the one hand and reduced side-information overhead for signaling the inter-layer dependencies on the other hand.
1. A device configured to process a data stream, representing an encoded video signal including a plurality of sets of video signals, each set of video signals including a multilayer video signal, the device being configured to:
read, from the data stream,
a first base layer-ID associated with a first set of video signals, the first base layer-ID being common for each layer of the multilayer video signal of the first set of video signals,
a first inter-dependency syntax structure indicating an inter-dependency between layers of the multilayer video signal of the first set of video signals, and
a second inter-dependency syntax structure indicating an inter-dependency between a layer of the multilayer video signal of the first set of video signals and a layer of the multilayer video signal of a second set of video signals; and
decode the encoded video signal based on the first inter-dependency syntax structure and the second inter-dependency syntax structure,
wherein the interdependency between layers of the multilayer video signal is based at least partially on a spatial relation or a coding dependency among layers of the multilayer video signal of the first set of video signals or between the layer of the multilayer video signal of the first set of video signals and the layer of the multilayer video signal of the second set of video signals.
2. The device of claim 1 , wherein the second inter-dependency syntax structure indicates whether the second set of video signals is a direct reference for the first set of video signals.
3. The device of claim 1 , the device being configured to read, from the data stream, a layer-ID associated with each layer of the multilayer video signal of the first set of video signals.
4. The device of claim 1 , wherein the multilayer video signal of at least one of the plurality of sets of video signals includes different layers encoded thereinto using inter-layer prediction such that any layer of the multilayer video signal that is inter-layer predicted from another layer of the multilayer video signal adds at least one of:
further views;
depth information;
alpha blending information;
color component information;
spatial resolution refinement; and
SNR resolution refinement.
5. The device of claim 1 , where the first inter-dependency syntax structure indicates interdependencies between different sets of layers of the multilayer video signal of the first set of video signals, each of the different sets of layers being associated with the first base layer-ID.
6. The device of claim 1 , wherein the device is configured to:
read, from the data stream, a plurality of instantiations of the second inter-dependency syntax structure for different pairs (j,k) of values 0<k≤j≤n<N representable by a base layer-ID, with N being the number of values representable by the base layer-ID, by
reading, or suppressing reading, the second inter-dependency structure from the data stream for pair (j,k) conditionally depending on the first inter-dependency syntax structure indicating a presence or non-presence of interdependency between pair (j,k),
wherein one of the plurality of instantiations of the second inter-dependency syntax structure read for a pair (j,k) with j=k, indicates which layers among those comprising base layer-ID j are inter-layer prediction dependent on other layers among those comprising base layer-ID j, and another of the plurality of instantiations of the second inter-dependency structure read for pair (j,k), with k<j indicates which layers among those comprising base layer-ID j are inter-layer prediction dependent on layers among those comprising base layer-ID k.
7. The device of claim 1 , wherein the device is configured to:
read instantiations of the second inter-dependency syntax structure from the data stream, along with, for each instantiation of the second inter-dependency syntax structure, an association syntax structure which associates the respective instantiation of the second inter-dependency syntax structure with a respective subset of pairs (j,k) of values 0<k≤j≤n<N representable by a base layer-ID, with N being the number of values representable by the base layer-ID.
8. An encoder configured to encode a video into a plurality of sets of video signals such that each set of video signals includes a multilayer video signal, the encoder being configured to:
insert, into a data stream representing an encoded video,
a first base layer-ID associated with a first set of video signals, the first base layer-ID being common for each layer of the multilayer video signal of the first set of video signals;
a first inter-dependency syntax structure indicating an inter-dependency between layers of the multilayer video signal of the first set of video signals; and
a second inter-dependency syntax structure indicating an inter-dependency between a layer of the multilayer video signal of the first set of video signals and a layer of the multilayer video signal of a second set of video signals,
wherein the encoded video is to be decoded based on the first inter-dependency syntax structure and the second inter-dependency syntax structure, and
the interdependency between layers of the multilayer video signal is based at least partially on a spatial relation or a coding dependency among layers of the multilayer video signal of the first set of video signals or between the layer of the multilayer video signal of the first set of video signals and the layer of the multilayer video signal of the second set of video signals.
9. The encoder of claim 8 , wherein the second inter-dependency syntax structure indicates whether the second set of video signals is a direct reference for the first set of video signals.
10. The encoder of claim 8 , the device being configured to insert, into the data stream, a layer-ID associated with each layer of the multilayer video signal of the first set of video signals.
11. The encoder of claim 8 , wherein the multilayer video signal of at least one of the plurality of sets of video signals includes different layers encoded thereinto using inter-layer prediction such that any layer of the multilayer video signal that is inter-layer predicted from another layer of the multilayer video signal adds at least one of:
further views;
depth information;
alpha blending information;
color component information;
spatial resolution refinement; and
SNR resolution refinement.
12. The encoder of claim 8 , where the first inter-dependency syntax structure indicates interdependencies between different sets of layers of the multilayer video signal of the first set of video signals, each of the different sets of layers being associated with the first base layer-ID.
13. The encoder of claim 8 , wherein the device is configured to:
insert, into the data stream, a plurality of instantiations of the second inter-dependency syntax structure for different pairs (j,k) of values 0<k≤j≤n<N representable by a base layer-ID, with N being the number of values representable by the base layer-ID, by
inserting, or suppressing inserting, the second inter-dependency structure into the data stream for pair (j,k) conditionally depending on the first inter-dependency syntax structure indicating a presence or non-presence of interdependency between pair (j,k),
wherein one of the plurality of instantiations of the second inter-dependency syntax structure inserted for a pair (j,k) with j=k, indicates which layers among those comprising base layer-ID j are inter-layer prediction dependent on other layers among those comprising base layer-ID j, and another of the plurality of instantiations of the second inter-dependency structure inserted for pair (j,k), with k<j indicates which layers among those comprising base layer-ID j are inter-layer prediction dependent on layers among those comprising base layer-ID k.
14. The encoder of claim 8 , wherein the device is configured to:
insert instantiations of the second inter-dependency syntax structure into the data stream, along with, for each instantiation of the second inter-dependency syntax structure, an association syntax structure which associates the respective instantiation of the second inter-dependency syntax structure with a respective subset of pairs (j,k) of values 0<k≤j≤n<N representable by a base layer-ID, with N being the number of values representable by the base layer-ID.
15. A non-transitory computer-readable medium for storing data associated with a video, comprising a data stream stored in the non-transitory computer-readable medium and representing an encoded video signal including a plurality of sets of video signals, each set of video signals including a multilayer video signal, the data stream comprising:
a first base layer-ID associated with a first set of video signals, the first base layer-ID being common for each layer of the multilayer video signal of the first set of video signals;
a first inter-dependency syntax structure indicating an inter-dependency between layers of the multilayer video signal of the first set of video signals; and
a second inter-dependency syntax structure indicating an inter-dependency between a layer of the multilayer video signal of the first set of video signals and a layer of the multilayer video signal of a second set of video signals,
wherein the encoded video is to be decoded based on the first inter-dependency syntax structure and the second inter-dependency syntax structure, and
the interdependency between layers of the multilayer video signal is based at least partially on a spatial relation or a coding dependency among layers of the multilayer video signal of the first set of video signals or between the layer of the multilayer video signal of the first set of video signals and the layer of the multilayer video signal of the second set of video signals.
16. The non-transitory computer-readable medium of claim 15 , wherein the second inter-dependency syntax structure indicates whether the second set of video signals is a direct reference for the first set of video signals.
17. The non-transitory computer-readable medium of claim 15 , the data stream further includes a layer-ID associated with each layer of the multilayer video signal of the first set of video signals.
18. The non-transitory computer-readable medium of claim 15 , wherein the multilayer video signal of at least one of the plurality of sets of video signals includes different layers encoded thereinto using inter-layer prediction such that any layer of the multilayer video signal that is inter-layer predicted from another layer of the multilayer video signal adds at least one of:
further views;
depth information;
alpha blending information;
color component information;
spatial resolution refinement; and
SNR resolution refinement.
19. The non-transitory computer-readable medium of claim 15 , where the first inter-dependency syntax structure indicates interdependencies between different sets of layers of the multilayer video signal of the first set of video signals, each of the different sets of layers being associated with the first base layer-ID.