Simplified advanced motion prediction for 3D-HEVC

1. A method for decoding multi-view video data, the method comprising:

dividing a current prediction unit (PU) into a plurality of sub-PUs, wherein the current PU is in a current picture;

determining default motion parameters, wherein the default motion parameters include a default motion vector and a default reference index, wherein determining the default motion parameters comprises:

setting the default motion vector to a zero motion vector; and

setting the default reference index to 0 or a first available temporal reference picture in a current reference picture list;

processing sub-PUs from the plurality of sub-PUs in a particular order, wherein processing the sub-PUs comprises, for at least one sub-PU from the plurality of sub-PUs:

determining a reference block for the sub-PU, wherein a reference picture includes the reference block for the sub-PU;

and

based on the reference block for the sub-PU not being coded using motion compensated prediction, setting the motion parameters of the sub-PU to the default motion parameters, wherein if the reference block for the sub-PU is not coded using motion compensated prediction, the motion parameters of the sub-PU are not set in response to a subsequent determination that a reference block for any later sub-PU in the particular order is coded using motion compensated prediction, wherein a reference block for at least one of the sub-PUs is not coded using motion compensated prediction; and

including a candidate in a candidate list of the current PU, wherein the candidate is based on the motion parameters of the plurality of sub-PUs;

obtaining, from a bitstream, a syntax element that indicates a selected candidate in the candidate list; and

using motion parameters of the selected candidate to reconstruct a predictive block for the current PU.

2. The method of claim 1 , wherein the reference picture is in a different view than the current picture; and

determining the reference block for the sub-PU comprises determining, based on a disparity vector of the current PU, a reference sample location in the reference picture, wherein the reference block for the sub-PU covers the reference sample location.

3. The method of claim 1 , wherein:

the current picture is a depth view component and the reference picture is a texture view component that is in the same view and access unit as the current picture; and

determining the reference block for the sub-PU comprises determining that the reference block for the sub-PU is a PU of the reference picture that is co-located with the sub-PU.

4. The method of claim 1 , further comprising determining, based on a PU-level motion vector candidate, whether to include a spatial merge candidate in the candidate list, wherein the PU-level motion vector candidate specifies the same motion parameters as the default motion parameters.

5. The method of claim 1 , wherein the default motion parameters are the same for each sub-PU in the plurality of sub-PUs.

6. A method of encoding video data, the method comprising:

dividing a current prediction unit (PU) into a plurality of sub-PUs, wherein the current PU is in a current picture;

determining default motion parameters, wherein the default motion parameters include a default motion vector and a default reference index, wherein determining the default motion parameters comprises:

setting the default motion vector to a zero motion vector; and

setting the default reference index to 0 or a first available temporal reference picture in a current reference picture list;

processing sub-PUs from the plurality of sub-PUs in a particular order, wherein processing the sub-PUs comprises, for at least one sub-PU from the plurality of sub-PUs:

determining a reference block for the sub-PU, wherein a reference picture includes the reference block for the sub-PU;

and

based on the reference block for the sub-PU not being coded using motion compensated prediction, setting the motion parameters of the sub-PU to the default motion parameters, wherein if the reference block for the sub-PU is not coded using motion compensated prediction, the motion parameters of the sub-PU are not set in response to a subsequent determination that a reference block for any later sub-PU in the particular order is coded using motion compensated prediction, wherein a reference block for at least one of the sub-PUs is not coded using motion compensated prediction; and

including a candidate in a candidate list of the current PU, wherein the candidate is based on the motion parameters of the plurality of sub-PUs; and

signaling, in a bitstream, a syntax element that indicates a selected candidate in the candidate list.

7. The method of claim 6 , wherein:

the reference picture is in a different view than the current picture; and

determining the reference block for the sub-PU comprises determining, based on a disparity vector of the current PU, a reference sample location in the reference picture, wherein the reference block for the sub-PU covers the reference sample location.

8. The method of claim 6 , wherein:

the current picture is a depth view component and the reference picture is a texture view component that is in the same view and access unit as the current picture; and

determining the reference block for the sub-PU comprises determining that the reference block for the sub-PU is a PU of the reference picture that is co-located with the sub-PU.

9. The method of claim 6 , further comprising determining, based on a PU-level motion vector candidate, whether to include a spatial merge candidate in the candidate list, wherein the PU-level motion vector candidate specifies the same motion parameters as the default motion parameters.

10. The method of claim 6 , wherein the default motion parameters are the same for each sub-PU in the plurality of sub-PUs.

11. A device for coding video data, the device comprising:

a memory for storing decoded pictures; and

one or more processors configured to:

divide a current prediction unit (PU) into a plurality of sub-PUs, wherein the current PU is in a current picture;

determine default motion parameters, wherein the default motion parameters include a default motion vector and a default reference index, wherein the one or more processors are configured to determine the default motion parameters at least in part by:

setting the default motion vector to a zero motion vector; and

setting the default reference index to 0 or a first available temporal reference picture in a current reference picture list;

process sub-PUs from the plurality of sub-PUs in a particular order, wherein the one or more processors are configured such that, as part of processing the sub-PUs, the one or more processors, for at least one sub-PU from the plurality of sub-PUs:

determine a reference block for the sub-PU, wherein a reference picture includes the reference block for the sub-PU;

based on the reference block for the sub-PU being coded using motion compensated prediction, set motion parameters of the sub-PU based on motion parameters of the reference block for the sub-PU; and

based on the reference block for the sub-PU not being coded using motion compensated prediction, set the motion parameters of the sub-PU to the default motion parameters, wherein if the reference block for the sub-PU is not coded using motion compensated prediction, the motion parameters of the sub-PU are not set in response to a subsequent determination that a reference block for any later sub-PU in the particular order is coded using motion compensated prediction, wherein a reference block for at least one of the sub-PUs is not coded using motion compensated prediction; and

include a candidate in a candidate list of the current PU, wherein the candidate is based on the motion parameters of the plurality of sub-PUs.

12. The device of claim 11 , wherein:

the reference picture is in a different view than the current picture; and

the one or more processors are configured to determine, based on a disparity vector of the current PU, a reference sample location in the reference picture, wherein the reference block for the sub-PU covers the reference sample location.

13. The device of claim 11 , wherein:

the current picture is a depth view component and the reference picture is a texture view component that is in the same view and access unit as the current picture; and

the one or more processors are configured to determine that the reference block for the sub-PU is a PU of the reference picture that is co-located with the sub-PU.

14. The device of claim 11 , wherein the one or more processors are configured to determine, based on a PU-level motion vector candidate, whether to include a spatial merge candidate in the candidate list, wherein the PU-level motion vector candidate specifies the same motion parameters as the default motion parameters.

15. The device of claim 11 , wherein the default motion parameters are the same for each sub-PU in the plurality of sub-PUs.

16. The device of claim 11 , wherein the one or more processors are further configured to:

obtain, from a bitstream, a syntax element that indicates a selected candidate in the candidate list; and

use motion parameters of the selected candidate to reconstruct a predictive block for the current PU.

17. The device of claim 11 , wherein the one or more processors are configured to signal, in a bitstream, a syntax element that indicates a selected candidate in the candidate list.

18. A device for coding video data, the device comprising:

means for dividing a current prediction unit (PU) into a plurality of sub-PUs, wherein the current PU is in a current picture;

means for determining default motion parameters, wherein the default motion parameters include a default motion vector and a default reference index, wherein the means for determining the default motion parameters comprise:

means for setting the default motion vector to a zero motion vector; and

means for setting the default reference index to 0 or a first available temporal reference picture in a current reference picture list;

means for processing sub-PUs from the plurality of sub-PUs in a particular order, wherein the means for processing the sub-PUs comprises, for at least one sub-PU from the plurality of sub-PUs:

means for determining a reference block for the sub-PU, wherein a reference picture includes the reference block for the sub-PU;

means for setting, based on the reference block for the sub-PU being coded using motion compensated prediction, motion parameters of the sub-PU based on motion parameters of the reference block for the sub-PU; and

means for setting, based on the reference block for the sub-PU not being coded using motion compensated prediction, the motion parameters of the sub-PU to the default motion parameters, wherein if the reference block for the sub-PU is not coded using motion compensated prediction, the motion parameters of the sub-PU are not set in response to a subsequent determination that a reference block for any later sub-PU in the particular order is coded using motion compensated prediction, wherein a reference block for at least one of the sub-PUs is not coded using motion compensated prediction; and

means for including a candidate in a candidate list of the current PU, wherein the candidate is based on the motion parameters of the plurality of sub-PUs.

19. A non-transitory computer-readable data storage medium having instructions stored thereon that when executed cause a device to:

divide a current prediction unit (PU) into a plurality of sub-PUs, wherein the current PU is in a current picture;

determine default motion parameters, wherein the default motion parameters include a default motion vector and a default reference index, wherein the instructions that cause the device to determine the default motion parameters comprise instructions that, when executed, cause the device to:

set the default motion vector to a zero motion vector; and

set the default reference index to 0 or a first available temporal reference picture in a current reference picture list;

process sub-PUs from the plurality of sub-PUs in a particular order, wherein processing the sub-PUs comprises, for each sub-PU from the plurality of sub-PUs:

determining a reference block for the sub-PU, wherein a reference picture includes the reference block for the sub-PU;

based on the reference block for the sub-PU being, setting motion parameters of the sub-PU based on motion parameters of the reference block for the sub-PU; and

based on the reference block for the sub-PU not being coded using motion compensated prediction, setting the motion parameters of the sub-PU to the default motion parameters, wherein if the reference block for the sub-PU is not coded using motion compensated prediction, the motion parameters of the sub-PU are not set in response to a subsequent determination that a reference block for any later sub-PU in the particular order is coded using motion compensated prediction, wherein a reference block for at least one of the sub-PUs is not coded using motion compensated prediction; and

include a candidate in a candidate list of the current PU, wherein the candidate is based on the motion parameters of the plurality of sub-PUs.

20. The method of claim 1 , wherein the sub-PU is a first sub-PU from the plurality of sub-PUs, and processing the sub-PUs comprises:

determining a reference block for a second sub-PU from the plurality of sub-PUs,

based on the reference block for the second sub-PU being coded using motion compensated prediction, setting motion parameters of the second sub-PU based on motion parameters of the reference block for the second sub-PU.

21. The method of claim 6 , wherein the sub-PU is a first sub-PU from the plurality of sub-PUs, and processing the sub-PUs comprises:

determining a reference block for a second sub-PU from the plurality of sub-PUs,

based on the reference block for the second sub-PU being coded using motion compensated prediction, setting motion parameters of the second sub-PU based on motion parameters of the reference block for the second sub-PU.