Reference index for enhancement layer in scalable video coding

Patent metadata

Field	Value
Publication number	US-9253487-B2
Application number	US-201313904336-A
Country	US
Kind code	B2
Filing date	May 29, 2013
Priority date	May 31, 2012
Publication date	Feb 2, 2016
Grant date	Feb 2, 2016

Abstract

An apparatus for coding video information according to certain aspects includes a memory unit and a processor in communication with the memory unit. The memory unit stores video information of a base, or reference, layer and an enhancement layer. The processor determines whether a base layer reference index is valid for the enhancement layer, and resolves mismatches between base layer and enhancement layer reference indices and reference frame picture order counts. Resolving mismatches may comprise deriving valid reference information from the base layer, using spatial motion information of video data associated with the reference information of the base and/or enhancement layers.

First claim

What is claimed is:

1. A method of decoding video data, the method comprising:
receiving syntax elements extracted from an encoded video bit stream, wherein the syntax elements comprise at least reference information associated with a co-located block in a first layer of the video data and reference information associated with a corresponding block in a second layer of the video data, and wherein the co-located block is located at a position in the first layer corresponding to a position of the corresponding block in the second layer;
determining whether the reference information associated with the co-located block in the first layer is invalid for the corresponding block in the second layer relative to the reference information associated with the second layer; and
in response to determining that the reference information associated with the co-located block in the first layer is invalid for the corresponding block in the second layer, determining valid reference information for the corresponding block in the second layer.

2. The method of claim 1 , further comprising:
in response to determining that the reference information associated with the co-located block in the first layer is valid relative to the reference information associated with the second layer, using at least some of the reference information associated with the co-located block in the first layer to code the corresponding block in the second layer according to a merge mode coding technique or an advanced motion vector prediction (AMVP) coding technique.

3. The method of claim 1 , wherein determining whether the reference information associated with the co-located block in the first layer is invalid for the corresponding block in the second layer relative to the reference information associated with the second layer comprises:
determining whether a reference index associated with the reference information of the first layer is an invalid reference index for the second layer.

4. The method of claim 3 , wherein a reference index associated with the reference information of the first layer is determined to be an invalid reference index for the second layer when there is no reference frame in a reference frame list of the second layer corresponding to the reference index of the co-located block in the first layer.

5. The method of claim 3 , wherein the reference information of the respective first and second layers includes one or more reference frames of the respective layers, and wherein the reference index of the first layer is an invalid reference index for the second layer when the number of reference frames in the reference index of the first layer is not equal to the number of reference frames in the reference index of the second layer.

6. The method of claim 3 , wherein determining valid reference information for the corresponding block in the second layer comprises converting a bi-directional motion vector associated with the reference information of the first layer to a uni-directional motion vector, wherein the bi-directional motion vector includes at least one reference index that is invalid for the corresponding block in the second layer.

7. The method of claim 3 , wherein determining valid reference information for the corresponding block in the second layer comprises marking one or more uni-directional motion vectors associated with the reference information of the first layer as unavailable.

8. The method of claim 1 , wherein the reference information associated with the co-located block in the first layer includes one or more first layer reference lists, and one or more first layer reference frames associated with each of the one or more first layer reference lists, and wherein the reference information associated with second layer includes one or more second layer reference frames, and wherein determining whether the reference information associated with the co-located block in the first layer is invalid for the corresponding block in the second layer relative to the reference information associated with the second layer comprises:
determining that none of the one or more second layer reference frames has a picture order count (POC) value equal to at least one picture order count (POC) value associated with the one or more first layer reference frames in at least one of the one or more first layer reference lists.

9. The method of claim 3 , wherein determining valid reference information for the corresponding block in the second layer comprises:
omitting one or more motion vectors associated with the reference information of the first layer from use for coding the second layer.

10. The method of claim 4 , wherein determining valid reference information for the corresponding block in the second layer comprises:
converting a reference index associated with the reference information of the first layer into a valid reference index for the second layer by setting the first reference index value for the reference index associated with the reference information of the first layer to a valid predefined reference index value for the second layer.

11. The method of claim 4 , wherein determining valid reference information for the corresponding block in the second layer comprises:
converting a reference index associated with the reference information of the first layer into a valid reference index for the second layer by setting the first reference index value for the reference index associated with the reference information of the first layer to zero or to a maximum reference index value for the reference index of the second layer.

12. The method of claim 8 , wherein determining valid reference information for the corresponding block in the second layer comprises:
omitting one or more motion vectors associated with the reference information of the first layer from use for coding the second layer.

13. The method of claim 1 , wherein determining valid reference information for the corresponding block in the second layer comprises:
evaluating one or more motion vectors associated with reference information of the second layer; and
deriving one or more motion vectors to be used in the second layer coding from the first layer using one or more of the evaluated motion vectors associated with the reference information of the second layer.

14. The method of claim 13 , wherein deriving one or more motion vector to be used in the second layer coding from the first layer further comprises scaling the one or more motion vectors from the first layer.

15. The method of claim 1 , wherein the reference information of the first and second layers include reference information related to one or more reference frames of the respective layers, and wherein the number of reference frames in a reference index associated with the reference information of the first layer is equal to the number of reference frames for the second layer.

16. The method of claim 1 , wherein the reference information of the first and second layers include reference information related to one or more reference frames of the respective layers, and wherein the one or more reference frames of the second layer comprise only the one or more reference frames of the first layer.

17. The method of claim 1 , wherein the first layer is a base layer and the second layer is an enhancement layer.

18. A method of encoding video data, the method comprising:
receiving reference information associated with a co-located block in a first layer of the video data and reference information associated with a corresponding block in a second layer of th

Assignees

• Qualcomm Inc

Inventors

• Seregin Vadim
• Wang Xianglin

Classifications

• H04N19/70

  characterised by syntax aspects related to video coding, e.g. related to compression standards · CPC title

• H04N19/00569 Primary

  Electricity · mapped topic

• H04N19/597

  specially adapted for multi-view video sequence encoding · CPC title

• H04N19/52 Primary

  by predictive encoding · CPC title

• H04N19/30

  using hierarchical techniques, e.g. scalability (H04N19/63 takes precedence) · CPC title