A method and apparatus of prediction for video coding using MH (Multiple Hypothesis) mode are disclosed. According to this method, a block is partitioned into a first partition and a second partition. A first candidate and a second candidate are derived for the first and second partitions respectively. At least one of the first candidate and the second candidate is derived using a candidate list derived for a regular Merge mode (or also called as normal Merge mode). An MH prediction generated by blending a first prediction corresponding to a first candidate and a second prediction corresponding to a second candidate, and the MH prediction is applied to a part of the current block.

A method for decoding or encoding comprising: determining if an inter prediction mode called weighted prediction is enabled for a current block; and, if weighted prediction is enabled, modifying a part of a reconstruction process of said current block related to the weighted prediction and/or to at least another prediction tool of a first set of prediction tools, the first set comprising a triangle prediction mode, a geometrical prediction mode, a local illumination compensation mode, a combined intra inter prediction mode, and modes in which motion information used for motion compensation may be refined based on an optical flow model.

A method for decoding encoded blocks of pixels from an encoded video bit stream is provided that includes decoding a block vector corresponding to an encoded block of pixels from the encoded bit stream, verifying that the block vector indicates a block of reconstructed pixels in a search area including reconstructed pixels of a largest coding unit (LCU) including the encoded block of pixels and N left neighboring reconstructed LCUs of the LCU, and decoding the encoded block of pixels, wherein the block of reconstructed pixels is used as a predictor for the encoded block of pixels.

A method for decoding encoded blocks of pixels from an encoded video bit stream is provided that includes decoding a block vector corresponding to an encoded block of pixels from the encoded bit stream, verifying that the block vector indicates a block of reconstructed pixels in a search area including reconstructed pixels of a largest coding unit (LCU) including the encoded block of pixels and N left neighboring reconstructed LCUs of the LCU, and decoding the encoded block of pixels, wherein the block of reconstructed pixels is used as a predictor for the encoded block of pixels.

A method is provided for inter-coding video in which transmission bandwidth requirements associated with second motion vectors for bi-directional temporal prediction is reduced. In the method, vector information for one of motion vectors for multi-directional temporal prediction can be transmitted together with information on how to derive or construct the second motion vectors. Thus, rather than sending express information regarding each of the plurality of motion vectors, express information related to only one motion vector along with information related to reconstruction/derivation of the second motion vectors is transmitted, thus reducing bandwidth requirements and increasing coding efficiency.

A method of video decoding including receiving a syntax element from a bitstream of a coded video associated with a current coding block that is partitioned into a first part and a second part along a partition edge for prediction in a geometric partitioning mode, and determining a weight index at a sample position of the current coding block. A stored motion vector type for a first motion storage unit in a motion field of the current coding block is determined based on a motion index of the first motion storage unit. The weight index at the sample position of the current coding block is used as the motion index of the first motion storage unit. The motion field of the current coding block can be stored based on the stored motion vector type determined for the first motion storage unit in the motion field of the current coding block.

Some operations associated with transform decoding may provide coding gains for intra-predicted coding blocks but not for coding blocks predicted using certain inter-prediction tools or techniques. These operations may include, for example, multiple transform selection (MTS) and/or transform skip, and the inter-prediction tools or techniques may include one or more of affine motion compensation, combined inter and intra prediction (CIIP), a triangular partition mode (TPM), or a geometric merge mode (GEO). Thus, systems, methods, and instrumentalities associated with versatile video coding may be configured such that the aforementioned operations associated with transform decoding may be disabled for coding blocks that are predicted using one or more the inter-prediction tools or techniques described herein. Many benefits may be derived from disabling these operations including, for example, reduction of encoding time and/or signaling overhead.

Some operations associated with transform decoding may provide coding gains for intra-predicted coding blocks but not for coding blocks predicted using certain inter-prediction tools or techniques. These operations may include, for example, multiple transform selection (MTS) and/or transform skip, and the inter-prediction tools or techniques may include one or more of affine motion compensation, combined inter and intra prediction (CIIP), a triangular partition mode (TPM), or a geometric merge mode (GEO). Thus, systems, methods, and instrumentalities associated with versatile video coding may be configured such that the aforementioned operations associated with transform decoding may be disabled for coding blocks that are predicted using one or more the inter-prediction tools or techniques described herein. Many benefits may be derived from disabling these operations including, for example, reduction of encoding time and/or signaling overhead.

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.