Method for decoder-side motion vector derivation using spatial correlation
AssigneesHyundai Motor Company, Kia Corporation
InventorsJin Heo, Seung Wook Park
Life of this patent
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Abstract
A method for decoder-side motion vector derivation utilizes a spatial correlation. A video coding method and apparatus minimize discontinuities at block boundaries, in order to overcome disadvantages of motion prediction that performs motion compensation on a per block basis. The video coding method and the apparatus derive, during decoder-side motion vector derivation, motion vectors by taking into account spatial correlation of the current block with surrounding blocks rather than deriving motion vectors by considering only the cost of a current and prediction block.
Claims19
A method performed by a video decoding device for refining a motion vector of a current block, the method comprising:
- obtaining an initial motion vector according to an inter-prediction mode of the current block;
- calculating a template matching cost by applying a template matching method to the current block and a plurality of reference blocks present in a search range of a reference picture with the initial motion vector as a reference;
- calculating a discontinuity measure at a boundary of each of the reference blocks;
- calculating a combined cost by a weighted summation with weights on the template matching cost and the discontinuity measure;
- selecting from the search range a reference block having a minimum of the combined cost;
- and
- generating a final motion vector by refining the initial motion vector based on motion information between the selected reference block and the current block,
- wherein a sum of the weights is equal to 1, and the weights each have a value in a range from 0 to 1.
A method performed by a video encoding device for refining a motion vector of a current block, the method comprising:
- determining an inter-prediction mode of the current block and an initial motion vector according to the inter-prediction mode;
- calculating a template matching cost by applying a template matching method to the current block and a plurality of reference blocks present in a search range of a reference picture with the initial motion vector as a reference;
- calculating a discontinuity measure at a boundary of each of the reference blocks;
- calculating a combined cost by a weighted summation with weights on the template matching cost and the discontinuity measure;
- and
- selecting from the search range a reference block having a minimum of the combined cost;
- and
- generating a final motion vector by refining the initial motion vector based on motion information between the selected reference block and the current block,
- wherein a sum of the weights is equal to 1, and the weights each have a value in a range from 0 to 1.
A non-transitory computer-recording medium storing instructions, when executed by a processor, to perform an encoding method for generating a bitstream comprising:
- determining an inter-prediction mode of a current block and an initial motion vector according to the inter-prediction mode;
- calculating a template matching cost by applying a template matching method to the current block and a plurality of reference blocks present in a search range of a reference picture with the initial motion vector as a reference;
- calculating a discontinuity measure at a boundary of each of the reference blocks;
- calculating a combined cost by a weighted summation with weights on the template matching cost and the discontinuity measure;
- selecting from the search range a reference block having a minimum of the combined cost;
- and generating a final motion vector by refining the initial motion vector based on motion information between the selected reference block and the current block,
- wherein a sum of the weights is equal to 1, and the weights each have a value in a range from 0 to 1.
Dependencies are inferred from the claim text.