Abstract: An electronic apparatus performs a method of coding video data. The method comprises: receiving, from the bitstream, syntax elements associated with a coding unit, wherein the syntax elements include a first coded block flag (CBF) for residual samples of a first chroma component, a second CBF for residual samples of a second chroma component, and a third syntax element indicating whether adaptive color transform (ACT) is applied to the coding unit; determining whether to perform the chroma residual scaling to the residual samples of the chroma components according to the first CBF, the second CBF, and the third syntax element; in accordance with a determination to perform the chroma residual scaling to the residual samples of the first and second chroma components, scaling the residual samples of the at least one of the first and second chroma components based on a corresponding scaling parameter.

Abstract: An electronic apparatus performs a method of decoding video data, comprising: receiving, from bitstream, a first syntax element in a slice header of a slice that indicates whether luma mapping with chroma scaling (LMCS) is applied to a coding unit in the slice; receiving a second syntax element for the coding unit that indicates whether the coding unit has been coded using adaptive color-space transform (ACT); if the second syntax element has a non-zero value, decoding the coding unit by applying inverse ACT to convert luma and chroma residuals of the coding unit from a transformed color space to an original color space of the video data; and if the first syntax element has a non-zero value, decoding the coding unit by performing inverse luma mapping to the luma samples and inverse scaling to the chroma residuals of the coding unit after performing the inverse ACT.

Abstract: An electronic apparatus performs a method of coding video data. The method comprises: receiving, from the bitstream, syntax elements associated with a coding unit, wherein the syntax elements include a first coded block flag (CBF) for residual samples of a first chroma component, a second CBF for residual samples of a second chroma component, and a third syntax element indicating whether adaptive color transform (ACT) is applied to the coding unit; determining whether to perform the chroma residual scaling to the residual samples of the chroma components according to the first CBF, the second CBF, and the third syntax element; in accordance with a determination to perform the chroma residual scaling to the residual samples of the first and second chroma components, scaling the residual samples of the at least one of the first and second chroma components based on a corresponding scaling parameter.

Abstract: An electronic apparatus performs a method of decoding video data, including receiving, from bitstream, a first syntax element in a slice header of a slice that indicates whether luma mapping with chroma scaling (LMCS) is applied to a coding unit in the slice; receiving a second syntax element for the coding unit that indicates whether the coding unit has been coded using adaptive color-space transform (ACT); if the second syntax element has a non-zero value, decoding the coding unit by applying inverse ACT to convert luma and chroma residuals of the coding unit from a transformed color space to an original color space of the video data; and if the first syntax element has a non-zero value, decoding the coding unit by performing inverse luma mapping to the luma samples and inverse scaling to the chroma residuals of the coding unit after performing the inverse ACT.

Abstract: An electronic apparatus performs a method of decoding video data, including receiving, from bitstream, a first syntax element in a slice header of a slice that indicates whether luma mapping with chroma scaling (LMCS) is applied to a coding unit in the slice; receiving a second syntax element for the coding unit that indicates whether the coding unit has been coded using adaptive color-space transform (ACT); if the second syntax element has a non-zero value, decoding the coding unit by applying inverse ACT to convert luma and chroma residuals of the coding unit from a transformed color space to an original color space of the video data; and if the first syntax element has a non-zero value, decoding the coding unit by performing inverse luma mapping to the luma samples and inverse scaling to the chroma residuals of the coding unit after performing the inverse ACT.

Abstract: An electronic apparatus performs a method of coding video data. The method comprises: receiving, from the bitstream, syntax elements associated with a coding unit, wherein the syntax elements include a first coded block flag (CBF) for residual samples of a first chroma component, a second CBF for residual samples of a second chroma component, and a third syntax element indicating whether adaptive color transform (ACT) is applied to the coding unit; determining whether to perform the chroma residual scaling to the residual samples of the chroma components according to the first CBF, the second CBF, and the third syntax element; in accordance with a determination to perform the chroma residual scaling to the residual samples of the first and second chroma components, scaling the residual samples of the at least one of the first and second chroma components based on a corresponding scaling parameter.

Abstract: Methods, apparatuses, and non-transitory computer-readable storage mediums are provided for decoding a video signal. A method may include obtain a first reference picture and a second reference picture associated with a video block, wherein the first reference picture is before a current picture and the second reference picture is after the current picture in display order; obtain first prediction samples of the video block from the first reference picture; obtain second prediction samples of the video block from the second reference picture; obtain padded prediction samples, and obtain horizontal and vertical gradient values of the first prediction samples and the second prediction samples based on the padded prediction samples; obtain motion refinements for samples in the video block based on the horizontal and vertical gradient values; and obtain bi-prediction samples of the video block based on the motion refinements.

Abstract: An electronic apparatus performs a method for video decoding. The method comprises: receiving, from a bitstream, a coding unit and determining a mode type condition of the coding unit; if the coding unit is encoded in a first chroma format, setting the mode type condition of the coding unit to a first mode type condition; if the coding unit is encoded in a second chroma format and the coding unit is a smallest chroma intra prediction unit, setting the mode type condition of the coding unit to a second mode type condition if a luma block of the coding unit and the splitting method satisfy a first criterion; setting the mode type condition of the coding unit to a third mode type condition if the luma block of the coding unit and the splitting method satisfy a second criterion, and decoding the coding unit based on the mode type condition.

Abstract: Methods, apparatuses, and non-transitory computer-readable storage mediums are provided for encoding a video signal. A method may include obtain a first reference picture associated with a video block in a current picture within the video signal and a first motion vector (MV) from the video block in the current picture to a reference block in the first reference picture; obtain first prediction samples I(i,j) of the video block generated from the reference block in the first reference picture; control internal bit-depths of internal prediction refinement with optical flow (PROF) parameters; obtain a prediction refinement value for the first prediction sample I(i,j); obtain second prediction samples I?(i,j) associated with a second MV and a corresponding prediction refinement value for a second prediction sample I?(i,j); and obtain a final prediction sample of the video block based on the first prediction sample I(i,j), the second prediction sample I?(i,j), and the prediction refinement values.

Abstract: An electronic apparatus performs a method for video decoding. The method comprises: receiving, from a bitstream, a coding unit and determining a mode type condition of the coding unit; if the coding unit is encoded in a first chroma format, setting the mode type condition of the coding unit to a first mode type condition; if the coding unit is encoded in a second chroma format and the coding unit is a smallest chroma intra prediction unit, setting the mode type condition of the coding unit to a second mode type condition if a luma block of the coding unit and the splitting method satisfy a first criterion; setting the mode type condition of the coding unit to a third mode type condition if the luma block of the coding unit and the splitting method satisfy a second criterion, and decoding the coding unit based on the mode type condition.

Abstract: Methods, apparatuses, and non-transitory computer-readable storage mediums are provided for encoding a video signal. A method may include obtain a first reference picture and a second reference picture associated with a video block, wherein the first reference picture is before a current picture and the second reference picture is after the current picture in display order; obtain first prediction samples of the video block from the first reference picture; obtain second prediction samples of the video block from the second reference picture; obtain padded prediction samples; obtain horizontal and vertical gradient values of the first prediction samples and the second prediction samples based on the padded prediction samples; obtain motion refinements for samples in the video block based on the horizontal and vertical gradient values; and obtain bi-prediction samples of the video block based on the motion refinements.

Abstract: Methods, apparatuses, and non-transitory computer-readable storage mediums are provided for coding a video signal. A method includes obtaining a first reference picture and a second reference picture associated with a video block; obtaining first prediction samples of the video block from the first reference picture; obtaining second prediction samples of the video block from the second reference picture; obtaining padded prediction samples, and obtaining horizontal and vertical gradient values of the first prediction samples and the second prediction samples based on the padded prediction samples; obtaining motion refinements for samples in the video block based on the horizontal and vertical gradient values; and obtaining bi-prediction samples of the video block based on the motion refinements.

Abstract: Methods, apparatuses, and non-transitory computer-readable storage mediums are provided for encoding a video signal.

Abstract: Methods, devices, and storage mediums are provided for decoding video signals. A decoder receives at least one versatile video coding (VVC) syntax flag. The decoder receives, in response to a syntax element indicating that inter prediction is allowed, inter related syntax elements. The decoder obtains a first reference picture I(0) and a second reference picture I(1) associated with a video block in a bitstream. The decoder obtains first prediction samples I(0)(i,j) of the video block from a reference block in the first reference picture I(0). The decoder obtains second prediction samples I(1)(i,j) of the video block from a reference block in the second reference picture I(1). The decoder obtains bi-prediction samples based on the at least one VVC syntax flag, the inter related syntax elements, the first prediction samples I(0)(i,j), and the second prediction samples I(1)(i,j).

Abstract: An electronic apparatus performs a method of decoding video data. The method comprises: receiving, from a bitstream, a first control flag that indicates merge mode with motion vector difference (MMVD) is enabled for one or more coding units in a video sequence; receiving a first syntax from the video data that identifies a set of motion vector difference (MVD) offsets from a plurality sets of MVD offsets; receiving, a second control flag corresponding to a respective coding unit of the one or more coding units, which indicates the MMVD is applied to the coding unit; receiving a second syntax that selects an MVD offset from the identified set of MVD offsets, and a third syntax that selects an MVD direction; forming MVD based on the selected MVD offset and MVD direction; and reconstructing the coding unit by applying the formed MVD to generate motion vectors to the coding unit.

Abstract: An electronic apparatus performs a method of decoding video data. The method comprises: receiving, from a bitstream, a first control flag that indicates merge mode with motion vector difference (MMVD) is enabled for one or more coding units in a video sequence; receiving a first syntax from the video data that identifies a set of motion vector difference (MVD) offsets from a plurality sets of MVD offsets; receiving, a second control flag corresponding to a respective coding unit of the one or more coding units, which indicates the MMVD is applied to the coding unit; receiving a second syntax that selects an MVD offset from the identified set of MVD offsets, and a third syntax that selects an MVD direction; forming MVD based on the selected MVD offset and MVD direction; and reconstructing the coding unit by applying the formed MVD to generate motion vectors to the coding unit.

Abstract: A computing device performs a method of decoding video data by receiving a bitstream corresponding to video data encoding one or more pictures, wherein the one or more pictures are recursively partitioned into a plurality of groups at different partition levels; determining a first syntax element that corresponds to a first group of the plurality of groups; in accordance with a determination that the first syntax element has a first value: decoding the first group in a first mode and in accordance with a determination that the first syntax element has a second value: determining a respective second syntax element for each of one or more second groups within the first groups, wherein the one or more second groups are at a second partition level below the first partition level and decoding each of the one or more second groups in accordance with a value of the respective second syntax element.

Abstract: An electronic apparatus performs a method of decoding video data. The method comprises: receiving, from a bitstream, a first control flag that indicates merge mode with motion vector difference (MMVD) is enabled for one or more coding units in a video sequence; receiving a first syntax from the video data that identifies a set of motion vector difference (MVD) offsets from a plurality sets of MVD offsets; receiving, a second control flag corresponding to a respective coding unit of the one or more coding units, which indicates the MMVD is applied to the coding unit; receiving a second syntax that selects an MVD offset from the identified set of MVD offsets, and a third syntax that selects an MVD direction; forming MVD based on the selected MVD offset and MVD direction; and reconstructing the coding unit by applying the formed MVD to generate motion vectors to the coding unit.

Abstract: An electronic apparatus performs a method of decoding video data. The method comprises: receiving the video signal that includes a first component and a second component; receiving a plurality of offsets associated with the second component; utilizing a characteristic measurement of the first component to obtain a classification category associated with the second component; selecting an offset from the plurality of offsets for the second component according to the classification category; and modifying the second component based on the selected offset. In some embodiments, the first component is a luma video component and the second component is a chroma video component.

Abstract: A computing device performs a method of decoding video data by determining a co-located picture of the current coding unit; locating a spatial neighbor block of the current coding unit that corresponds to the co-located picture; determining a motion shift vector for the current coding unit from one or more motion vectors associated with the spatial neighbor block according to a predefined fixed order; and reconstructing a sub-block-based temporal motion vector for a respective sub-block of a plurality of sub-blocks in the current coding unit from a corresponding sub-block in the collocated picture based on the motion shift vector.