Encoding and deriving parameters for coded multi-layer video sequences

• US 10,609,394 B2
• Filed: 04/23/2013
• Issued: 03/31/2020
• Est. Priority Date: 04/24/2012
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Rusert, Thomas
• Primary Examiner(s): Czekaj, Dave
• Assistant Examiner(s): Abimbola, Kehinde
• Application Number:
  US14/395,563
• Publication Number:
  US 20150334407A1
• Time in Patent Office: 2,534 Days
• CPC Class Codes: H04N 19/184 the unit being bits, e.g. of the compressed video stream
• CPC Class Codes: H04N 19/30 using hierarchical techniques, e.g. scalability H04N19/63 takes precedence
• CPC Class Codes: H04N 19/463 by compressing encoding parameters before transmission
• CPC Class Codes: H04N 19/70 characterised by syntax aspects related to video coding, e.g. related to compression standards

Abstract

A method of deriving parameters required for decoding a current layer of a coded multi-layer video sequence. The method comprises deriving a required parameter from one or more parameters associated with the current or a lower layer of the multiple layers. The invention makes use of an understanding that parameters which are required for decoding a current higher layer of a multi-layer video representation may be derived, i.e., inferred or predicted, from parameters associated with lower layers rather than explicitly signaled in a parameter set associated with the current layer. Also disclosed are a method of encoding parameters associated with such a current layer, corresponding computer program products, a corresponding parameter set decoder, and a corresponding parameter set encoder.

Claims

1. A method of deriving parameters required for decoding a current layer of a video bitstream comprising multiple layers, the method comprising:

obtaining, from a current layer parameter set associated with decoding the current layer of the video bitstream, a reference to a lower layer parameter set associated with decoding a lower layer of the multiple layers of the video bitstream, wherein the reference to the lower layer parameter set is signaled in the current layer parameter set;

responsive to obtaining the reference to the lower layer parameter set from the current layer parameter set, deriving a parameter required for decoding the current layer from a parameter of the lower layer parameter set, wherein the parameter required for decoding the current layer is not signaled explicitly but is predicted from the parameter of the lower layer parameter set used for decoding the lower layer,

wherein the reference comprises a parameter type identifier of the lower layer parameter set;

wherein the lower layer parameter set is one of several different parameter sets of the lower layer; and

wherein deriving the parameter required for decoding the current layer comprises selecting the lower layer parameter set from the several different parameter sets of the lower layer based on the parameter type identifier.

2. The method according to claim 1, wherein the parameter required for decoding the current layer is derived from a sum of a first parameter of the lower layer parameter set and a second parameter of the current layer parameter set.

3. The method according to claim 1, wherein the parameter required for decoding the current layer is derived from a sum of a first parameter of the lower layer parameter set and a predetermined second parameter.

4. The method according to claim 1, wherein the parameter of the lower layer parameter set comprises a predetermined parameter value.

5. A computer program product comprising a non-transitory computer readable storage medium storing computer program code, the computer program code being adapted, when executed on a processor, to implement the method according to claim 1.

17. The method according to claim 1, wherein deriving a parameter required for decoding the current layer from the parameter of the lower layer parameter set comprises deriving the parameter required for decoding the current layer from a parameter of the lower layer which is active for the referenced lower layer when a flag is present in the parameter set associated with the current layer, the flag identifying which parameter active in the referenced lower layer parameter set should be used for deriving the parameter required for decoding the current layer.

18. The method according to claim 1, further comprising:

determining parameters required for decoding the current layer that can be derived from an active parameter set of the referenced lower layer based on the determined reference.

20. The method according to claim 1, wherein the reference comprises a layer identifier of the lower layer and a parameter set identifier of the lower layer parameter set.

6. A method of encoding parameters associated with a current layer of a video bitstream comprising multiple layers, the method comprising:

obtaining a plurality of parameters to be signaled in a current layer parameter set of the current layer of the video bitstream,

obtaining a reference to a lower layer parameter set of the multiple layers of the video bitstream;

determining a lower layer parameter set of the lower layer of the video bitstream based on the reference,

determining one or more of the plurality of parameters to be signaled in the current layer parameter set are predictable from one or more parameters of the lower layer parameter set of the lower layer of the video bitstream,

encoding the reference to the lower layer parameter set into the current layer parameter set of the current layer of the video bitstream while omitting the one or more of the plurality of parameters to be signaled in the current layer parameter set which are predictable from one or more parameters of the lower layer parameter set,

determining one or more of the plurality of parameters to be signaled in the current layer parameter set that are not predictable from the one or more parameters of the lower layer parameter set of the lower layer of the video bitstream,

encoding the one or more of the plurality of parameters to be signaled that are not predictable from the one or more parameters of the lower layer parameter set into the current layer parameter set of the current layer of the video bitstream,

signaling the current layer parameter set of the current layer comprising the reference to the lower layer parameter set and the one or more of the plurality of parameters that are not predictable from the one or more parameters of the lower layer parameter set in the video bitstream,

wherein the lower layer parameter set is one of several different parameter sets of the lower layer, and

wherein deriving the parameter required for decoding the current layer comprises selecting the lower layer parameter set from the several different parameter sets of the lower layer based on a parameter type identifier of the lower layer parameter set.

7. The method according to claim 6, wherein the reference comprises a layer identifier of the lower layer and a parameter set identifier of the lower layer parameter set.

8. A computer program product comprising a non-transitory computer readable storage medium storing computer program code, the computer program code being adapted, when executed on a processor, to implement the method according to claim 6.

19. The method according to claim 6, wherein signaling the current layer parameter set further comprises including a flag into the signaled current layer parameter set indicating which parameters of the signaled current layer parameter set are predictable from the signaled reference to the lower layer parameter set.

9. A parameter set decoder for deriving parameters required for decoding a current layer of a video bitstream comprising multiple layers, the decoder comprising a processor that is configured to perform operations comprising:

obtaining, from a current layer parameter set associated with decoding the current layer of the video bitstream, a reference to a lower layer parameter set associated with decoding a lower layer of the multiple layers of the video bitstream, wherein the reference to the lower layer parameter set is signaled in the current layer parameter set; and

responsive to obtaining the reference to the lower layer parameter set from the current layer parameter set, deriving a parameter required for decoding the current layer from a parameter of the lower layer parameter set, wherein the parameter required for decoding the current layer is not signaled explicitly but is predicted from the parameter of the lower layer parameter set used for decoding the lower layer,

wherein the reference comprises a parameter type identifier of the lower layer parameter set;

wherein the lower layer parameter set is one of several different parameter sets of the lower layer; and

wherein deriving the parameter required for decoding the current layer comprises selecting the lower layer parameter set from the several different parameter sets of the lower layer based on the parameter type identifier.

10. The parameter set decoder according to claim 9, wherein the parameter required for decoding the current layer is derived from a sum of a first parameter of the lower layer parameter set and a second parameter of the current layer parameter set.

11. The parameter set decoder according to claim 9, wherein the parameter required for decoding the current layer is derived from a sum of a first parameter of the lower layer parameter set and a predetermined second parameter.

12. The parameter set decoder according to claim 9, wherein the parameter of the lower layer parameter set comprises a predetermined parameter value.

13. A video decoder comprising a parameter set decoder according to claim 9.

14. A parameter set encoder for encoding parameters associated with a current layer of a video bitstream comprising multiple layers, the encoder comprising a processor that is configured to perform operations comprising:

obtaining a plurality of parameters to be signaled in a current layer parameter set of the current layer of the video bitstream,

obtaining a reference to a lower layer parameter set of the multiple layers of the video bitstream;

determining a lower layer parameter set of the lower layer of the video bitstream based on the reference,

determining one or more of the plurality of parameters to be signaled in the current layer parameter set are predictable from one or more parameters of the lower layer parameter set of the lower layer of the video bitstream,

encoding the reference to the lower layer parameter set into the current layer parameter set of the current layer of the video bitstream while omitting the one or more of the plurality of parameters to be signaled in the current layer parameter set which are predictable from one or more parameters of the lower layer parameter set,

determining one or more of the plurality of parameters to be signaled in the current layer parameter set that are not predictable from the one or more parameters of the lower layer parameter set of the lower layer of the video bitstream,

encoding the one or more of the plurality of parameters to be signaled that are not predictable from the one or more parameters of the lower layer parameter set into the current layer parameter set of the current layer of the video bitstream, and

signaling the current layer parameter set of the current layer comprising the reference to the lower layer parameter set and the one or more of the plurality of parameters that are not predictable from the one or more parameters of the lower layer parameter set in the video bitstream,

wherein the lower layer parameter set is one of several different parameter sets of the lower layer, and

wherein deriving the parameter required for decoding the current layer comprises selecting the lower layer parameter set from the several different parameter sets of the lower layer based on a parameter type identifier of the lower layer parameter set.

15. The parameter set encoder according to claim 14, wherein the reference comprises a layer identifier of the lower layer and a parameter set identifier of the lower layer parameter set.

16. A video encoder comprising a parameter set encoder according to claim 14.