Method and apparatus for motion estimation using combined reference bi-prediction
A method and apparatus are provided for motion estimation using combined reference bi-prediction. The apparatus includes an encoder ( 200 ) for encoding a multi-prediction picture from a combination of two or more reference pictures by respectively predicting a motion vector for a particular one of the two or more reference pictures in a motion estimation process while initializing motion vectors for remaining ones of the two or more reference pictures to a predefined value for use by the motion estimation process.
1. An apparatus, comprising:
an encoder for encoding a multi-prediction picture from a combination of two or more reference pictures by respectively predicting a motion vector for a particular one of the two or more reference pictures in a motion estimation process while initializing motion vectors for remaining ones of the two or more reference pictures to a predefined value for use by the motion estimation process,
wherein the predefined value, to which the motion vectors for the remaining ones of the two or more reference pictures are initialized, is constrained to a value representative of the remaining ones of the two or more reference pictures being stationary, and wherein said encoder jointly computes the motion vectors for the two or more reference pictures based on the two or more reference pictures having identical motion with respect to the multi-prediction picture to be encoded.
2. The apparatus of claim 1 , wherein said encoder jointly computes the motion vectors for the two or more reference pictures by selecting a respective weight there for.
3. A method, comprising:
encoding a multi-prediction picture from a combination of two or more reference pictures by respectively predicting a motion vector for a particular one of the two or more reference pictures in a motion estimation process while initializing motion vectors for remaining ones of the two or more reference pictures to a predefined value for use by the motion estimation process,
wherein the predefined value, to which the motion vectors for the remaining ones of the two or more reference pictures are initialized, is constrained to a value representative of the remaining ones of the two or more reference pictures being stationary, and wherein said encoding jointly computes the motion vectors for the two or more reference pictures based on the two or more reference pictures having identical motion with respect to the multi-prediction picture to be encoded.
4. The method of claim 3 , wherein said encoding jointly computes the motion vectors for the two or more reference pictures by selecting a respective weight there for.
5. The apparatus of claim 1 , wherein said encoder estimates the motion vectors for the two or more reference pictures based on weights used for the two or more reference pictures from a previous weight estimation process.
6. The method of claim 3 , wherein said encoding estimates the motion vectors for the two or more reference pictures based on weights used for the two or more reference pictures from a previous weight estimation process.
7. The apparatus of claim 1 , wherein the particular one of the two or more reference pictures has a highest distortion compared to the multi-prediction picture from among all of the two or more reference pictures.
8. The method of claim 3 , wherein the particular one of the two or more reference pictures has a highest distortion compared to the multi-prediction picture from among all of the two or more reference pictures.