A method for intra-prediction of a current block includes selecting peripheral pixels of the current block, where the peripheral pixels are used to generate a prediction block for the current block; for each prediction pixel of the prediction block, performing steps including selecting two respective pixels of the peripheral pixels; and calculating the prediction pixel by interpolating at least the two respective pixels; and coding a residual block corresponding to a difference between the current block and the prediction block.

A method for intra-prediction of a current block includes selecting peripheral pixels of the current block, where the peripheral pixels are used to generate a prediction block for the current block; for each prediction pixel of the prediction block, performing steps including selecting two respective pixels of the peripheral pixels; and calculating the prediction pixel by interpolating at least the two respective pixels; and coding a residual block corresponding to a difference between the current block and the prediction block.

Described is picture segmentation through columns and slices in video encoding and decoding. A video picture is divided into a plurality of columns, each column covering only a part of the video picture in a horizontal dimension. All coded tree blocks (“CTBs”) belonging to a slice may belong to one or more columns. The columns may be used to break the same or different prediction or in-loop filtering mechanisms of the video coding, and the CTB scan order used for encoding and/or decoding may be local to a column. Column widths may be indicated in a parameter set and/or may be adjusted at the slice level. At the decoder, column width may be parsed from the bitstream, and slice decoding may occur in one or more columns.

Described is picture segmentation through columns and slices in video encoding and decoding. A video picture is divided into a plurality of columns, each column covering only a part of the video picture in a horizontal dimension. All coded tree blocks (“CTBs”) belonging to a slice may belong to one or more columns. The columns may be used to break the same or different prediction or in-loop filtering mechanisms of the video coding, and the CTB scan order used for encoding and/or decoding may be local to a column. Column widths may be indicated in a parameter set and/or may be adjusted at the slice level. At the decoder, column width may be parsed from the bitstream, and slice decoding may occur in one or more columns.

The present disclosure provides a method and an apparatus for determining an intra-frame prediction mode of a current video block. The method includes determining, in an image area including a to-be-coded current video block, reference modes of the current video block based on a plurality of intra-frame prediction modes of a plurality of second video blocks, the image area being in an area defined by an adjacent coding unit (CU) and a father CU corresponding to the current video block in a video frame or slice including the current video block; determining an alternative prediction mode set from preset intra-frame prediction modes, the alternative prediction mode set comprising a plurality of alternative prediction modes, including the reference modes; and determining, in the alternative prediction mode set, a prediction mode having optimal intra-frame prediction coding performance on the current video block as an intra-frame prediction mode of the current video block.

The present disclosure provides a method and an apparatus for determining an intra-frame prediction mode of a current video block. The method includes determining, in an image area including a to-be-coded current video block, reference modes of the current video block based on a plurality of intra-frame prediction modes of a plurality of second video blocks, the image area being in an area defined by an adjacent coding unit (CU) and a father CU corresponding to the current video block in a video frame or slice including the current video block; determining an alternative prediction mode set from preset intra-frame prediction modes, the alternative prediction mode set comprising a plurality of alternative prediction modes, including the reference modes; and determining, in the alternative prediction mode set, a prediction mode having optimal intra-frame prediction coding performance on the current video block as an intra-frame prediction mode of the current video block.

A method for processing a video includes performing a conversion between a current block of visual media data and a corresponding coded representation of the visual media data, wherein the conversion of the current block includes determining whether a use of one or both of a bi-directional optical flow (BIO) technique or a decoder-side motion vector refinement (DMVR) technique to the current block is enabled or disabled, and wherein the determining the use of the BIO technique or the DMVR technique is based on a cost criterion associated with the current block.

A method for processing a video includes performing a conversion between a current block of visual media data and a corresponding coded representation of the visual media data, wherein the conversion of the current block includes determining whether a use of one or both of a bi-directional optical flow (BIO) technique or a decoder-side motion vector refinement (DMVR) technique to the current block is enabled or disabled, and wherein the determining the use of the BIO technique or the DMVR technique is based on a cost criterion associated with the current block.

A video decoder, encoder, and corresponding methods for processing video data for an image block and a particular reference picture index to predict the image block are disclosed that utilize adaptive weighting of reference pictures to enhance video compression, where a decoder includes a reference picture weighting factor unit for determining a weighting factor corresponding to the particular reference picture index; an encoder includes a reference picture weighting factor assignor for assigning a weighting factor corresponding to the particular reference picture index; and a method for decoding includes receiving a reference picture index with the data that corresponds to the image block, determining a weighting factor for each received reference picture index, retrieving a reference picture for each index, motion compensating the retrieved reference picture, and multiplying the motion compensated reference picture by the corresponding weighting factor to form a weighted motion compensated reference picture.

A video decoder, encoder, and corresponding methods for processing video data for an image block and a particular reference picture index to predict the image block are disclosed that utilize adaptive weighting of reference pictures to enhance video compression, where a decoder includes a reference picture weighting factor unit for determining a weighting factor corresponding to the particular reference picture index; an encoder includes a reference picture weighting factor assignor for assigning a weighting factor corresponding to the particular reference picture index; and a method for decoding includes receiving a reference picture index with the data that corresponds to the image block, determining a weighting factor for each received reference picture index, retrieving a reference picture for each index, motion compensating the retrieved reference picture, and multiplying the motion compensated reference picture by the corresponding weighting factor to form a weighted motion compensated reference picture.