An encoder is provided that comprises a partitioner and an entropy coder. The partitioner is configured to receive a current block of the frame and obtain a list of candidate geometric partitioning (GP) lines. Each of the candidate GP lines is generated based on information of one or more candidate neighbor blocks of the current block. The partitioner is further configured to determine a final GP line that partitions the current block into two segments, select a GP line from the list of GP lines to obtain a selected GP line, and generate a GP parameter for the current block. The GP parameter includes an offset information indicating an offset between the final GP line and the selected GP line. The entropy coder is configured to encode the GP parameter.

A method of decoding video data includes determining that a geometric partition mode is enabled for a current block of the video data and determining a split line dividing the current block into a first partition and a second partition, where determining the split line comprises selecting an angle for the split line from a plurality of angles, Each angle of the plurality of angles corresponding to an N:M ratio of samples of the current block, where N and M are integers. The split line is not at a corner of the current block. The method further includes determining geometric mode weights for the current block using the angle of the split line, generating a first prediction block using motion information for the first partition, and generating a second prediction block using motion information for the second partition.

A video decoding method performed by a video decoding apparatus according to the present document may comprise the steps of: parsing a prediction weighted table syntax from a bitstream; parsing number information about weighted reference pictures in a reference picture list from the prediction weighted table syntax; deriving a weighting factor-related flag about the reference picture list on the basis of the number information; performing weighted prediction on a current block on the basis of the weighting factor-related flag so as to derive prediction samples of the current block; generating residual samples on the basis of residual information obtained from the bitstream; and reconstructing a current picture on the basis of the prediction samples and the residual samples, wherein the prediction weighted table syntax is parsed from a picture header of the bitstream.

A video decoding method performed by a video decoding apparatus according to the present document may comprise the steps of: parsing a prediction weighted table syntax from a bitstream; parsing number information about weighted reference pictures in a reference picture list from the prediction weighted table syntax; deriving a weighting factor-related flag about the reference picture list on the basis of the number information; performing weighted prediction on a current block on the basis of the weighting factor-related flag so as to derive prediction samples of the current block; generating residual samples on the basis of residual information obtained from the bitstream; and reconstructing a current picture on the basis of the prediction samples and the residual samples, wherein the prediction weighted table syntax is parsed from a picture header of the bitstream.

A method for motion estimation, a non-transitory computer-readable storage medium, and an electronic device are provided. The method includes the following. An error between a block to be matched and each of reference blocks is determined to obtain multiple errors. At least one candidate block is determined from the reference blocks according to the multiple errors. A random number range is determined according to a displacement between the block to be matched and each of the reference blocks. Random motion vectors are obtained by using a motion vector between the block to be matched and each of the at least one candidate block as a basic motion vector and random numbers within the random number range as increments. A target motion vector corresponding to the block to be matched is determined according to the random motion vectors.

A method for motion estimation, a non-transitory computer-readable storage medium, and an electronic device are provided. The method includes the following. An error between a block to be matched and each of reference blocks is determined to obtain multiple errors. At least one candidate block is determined from the reference blocks according to the multiple errors. A random number range is determined according to a displacement between the block to be matched and each of the reference blocks. Random motion vectors are obtained by using a motion vector between the block to be matched and each of the at least one candidate block as a basic motion vector and random numbers within the random number range as increments. A target motion vector corresponding to the block to be matched is determined according to the random motion vectors.

A video decoding method performed by a video decoding apparatus, according to the present document, comprises the steps of: parsing a flag for weighted prediction from a bitstream; parsing a prediction weighted table syntax from the bitstream on the basis of the flag; generating prediction samples by performing weighted prediction on a current block within a current picture on the basis of the prediction weighted table syntax; and generating reconstructed samples for the current block on the basis of the prediction samples, wherein the prediction weighted table syntax may be parsed from a picture header or slice header of the bitstream on the basis of a value of the flag.

A video decoding method performed by a video decoding apparatus, according to the present document, comprises the steps of: parsing a flag for weighted prediction from a bitstream; parsing a prediction weighted table syntax from the bitstream on the basis of the flag; generating prediction samples by performing weighted prediction on a current block within a current picture on the basis of the prediction weighted table syntax; and generating reconstructed samples for the current block on the basis of the prediction samples, wherein the prediction weighted table syntax may be parsed from a picture header or slice header of the bitstream on the basis of a value of the flag.

An image encoding method for encoding an image includes: a prediction image generation step of generating a synthesis-prediction image by performing synthesis processing of synthesizing an inter-prediction image and an intra-prediction image to an encoding-target block; and an encoding step of encoding a difference between the prediction image generated in the prediction image generation step and a pixel value of an image of the encoding-target block, the synthesis processing includes weighting processing performed to the inter-prediction image and the intra-prediction image, a weighting parameter in the weighting processing is determined in accordance with a type of the intra prediction of the encoding-target block and a combination of prediction modes of a plurality of adjacent blocks adjacent to the encoding-target block, and types of the intra prediction of the encoding-target block include a matrix weighting intra prediction.

Motion vectors of a first reference frame are permitted to point to a plurality of further reference frames. A method of storing the motion vectors comprises, when a block of the first reference frame has two motion vectors (V2A, V2B) initially, selecting one of the two motion vectors, the non-selected motion vector not being stored. The selected motion vector may be scaled. This can reduce the motion vector memory size.