Method and apparatus of motion vector derivation 3D video coding
A method and apparatus for three-dimensional and multi-view video coding are disclosed, where the motion vector (MV) or disparity vector (DV) candidate list construction process for a block depends on whether the target reference picture corresponds to an inter-view reference picture or whether the inter-view candidate refers to an inter-view reference picture. In one embodiment, an MV or DV candidate list for a block coded in Merge mode is constructed, and an inter-view candidate in the MV or DV candidate list is set lower than the first candidate position if the inter-view candidate refers to an inter-view reference picture. In another embodiment, an MV or DV candidate list for a block coded in advanced motion vector prediction mode is constructed, and an inter-view candidate is set lower than the first candidate position if the inter-view candidate refers to an inter-view reference picture.
1. A method for three-dimensional video coding and multi-view video coding, the method comprising:
receiving input data associated with a current block in a dependent view, wherein Advanced Motion Vector Prediction (AMVP) mode is selected for the current block;
deriving a first candidate referring to one reference picture corresponding to an inter-view reference picture, wherein said deriving the first candidate comprises deriving an estimated disparity vector (DV) from neighboring disparity vectors (DVs) associated with neighboring blocks of the current block, and wherein if the estimated DV is not available, a default non-zero DV is used as the estimated DV;
deriving a second candidate referring to one reference picture corresponding to a non-inter-view reference picture,
constructing an AMVP candidate list comprising the first candidate and the second candidate, wherein the first candidate is set to a lower priority position in the AMVP candidate list than the second candidate; and
applying three-dimensional or multi-view video encoding or decoding to the input data associated with the current block using the AMVP candidate list.
2. The method of claim 1 , wherein said deriving the estimated DV generates the estimated DV by searching through the neighboring DVs associated with the neighboring blocks of the current block and selects a first available DV as the estimated DV.
3. The method of claim 1 , wherein said deriving the estimated DV generates the estimated DV and also generates candidate members of the AMVP candidate list by searching through neighboring motion information associated with the neighboring blocks of the current block.
4. The method of claim 3 , wherein each of the neighboring motion information associated with one neighboring block is searched at most once.
5. The method of claim 1 , wherein information associated with the default non-zero DV is signaled in a bitstream generated by the three-dimensional video coding or the multi-view video coding.
6. The method of claim 5 , wherein the information associated with the default non-zero DV is signaled in the bitstream for a sequence, picture, or a slice or region of the picture.
7. The method of claim 1 , wherein the second candidate comprises a motion vector (MV) associated with a corresponding block in a reference view derived from a disparity vector (DV), and the second candidate is placed at first position in the AMVP candidate list.
8. An apparatus for three-dimensional and multi-view video coding, comprising:
one or more electronic circuits, wherein said one or more electronic circuits are configured to:
receive input data associated with a current block in a dependent view;
derive a first candidate referring to one reference picture corresponding to an inter-view reference picture, wherein said deriving the first candidate comprises deriving an estimated disparity vector (DV) from neighboring disparity vectors (DVs) associated with neighboring blocks of the current block, and wherein if the estimated DV is not available, a default non-zero DV is used as the estimated DV;
derive a second candidate referring to one reference picture corresponds to a non-inter-view reference picture;
construct a AMVP candidate list comprising the first candidate and the second candidates, wherein the first candidate is set to a lower priority position in the AMVP candidate list than the second candidate; and
apply three-dimensional/multi-view video encoding or decoding to the input data associated with the current block using the AMVP candidate list.