Abstract: A method of de-blocking an edge of a block of samples of video data is disclosed. A first prediction mode is decoded for a first block of two adjacent blocks of video data, each of the blocks of video data including a primary color channel and at least one secondary color channel. A second prediction mode is decoded for a second block of the two adjacent blocks of video data. A boundary strength value is determined for a block of samples along an edge corresponding to a boundary between said first block of video data and said second block of video data. A weak de-blocking filter is applied to the block of data along said edge if the determined boundary strength value indicates that the first prediction mode is intra prediction and the second prediction mode is intra-block copy prediction. The weak de-blocking filter is different to a filter applied to a block determined to have two, adjacently located, intra prediction mode blocks.

Abstract: Disclosed is a method of decoding residual coefficients of a transform unit from a bitstream of video data. The method receives the transform unit (1500) from the bitstream of video data in which the transform unit has upper (1503) and lower (1502) level square layers. The upper level layer represents a square arrangement of at most four significant coefficient group flags with each of the significant coefficient group flags representing a non-overlapping region of the lower level layer. The method determines determining the significant coefficient group flags of the square upper level layer for the received transform unit, and determines values of residual coefficients of the square lower layer according to the determined significant coefficient group flags to decode the transform unit of the bitstream of video data. Corresponding encoding methods are also disclosed.

Abstract: Disclosed is a method of decoding residual coefficients of a transform unit from a bitstream of video data. The method receives the transform unit (1500) from the bitstream of video data in which the transform unit has upper (1503) and lower (1502) level square layers. The upper level layer represents a square arrangement of at most four significant coefficient group flags with each of the significant coefficient group flags representing a non-overlapping region of the lower level layer. The method determines determining the significant coefficient group flags of the square upper level layer for the received transform unit, and determines values of residual coefficients of the square lower layer according to the determined significant coefficient group flags to decode the transform unit of the bitstream of video data. Corresponding encoding methods are also disclosed.

Abstract: Disclosed is a method of decoding residual coefficients of a transform unit from a bitstream of video data. The method receives the transform unit (1500) from the bitstream of video data in which the transform unit has upper (1503) and lower (1502) level square layers. The upper level layer represents a square arrangement of at most four significant coefficient group flags with each of the significant coefficient group flags representing a non-overlapping region of the lower level layer. The method determines determining the significant coefficient group flags of the square upper level layer for the received transform unit, and determines values of residual coefficients of the square lower layer according to the determined significant coefficient group flags to decode the transform unit of the bitstream of video data. Corresponding encoding methods are also disclosed.

Abstract: Disclosed is a method of decoding residual coefficients of a transform unit from a bitstream of video data. The method receives the transform unit (1500) from the bitstream of video data in which the transform unit has upper (1503) and lower (1502) level square layers. The upper level layer represents a square arrangement of at most four significant coefficient group flags with each of the significant coefficient group flags representing a non-overlapping region of the lower level layer. The method determines determining the significant coefficient group flags of the square upper level layer for the received transform unit, and determines values of residual coefficients of the square lower layer according to the determined significant coefficient group flags to decode the transform unit of the bitstream of video data. Corresponding encoding methods are also disclosed.

Abstract: A method of displaying images on a display. Images from a video playback are displayed on the display with a first luminance profile, the luminance profile mapping video data samples to output luminance of the display. A user initiated modification of a speed of the video playback is detected. A second luminance profile is determined for the display of the video playback, the second luminance profile being determined according to the modified speed of the video playback and a predetermined adaptation speed of a human visual system of a viewer of the video playback. Further images from the video playback are displayed on the display using the determined second luminance profile.

Abstract: A method of decoding a coding unit from a video bitstream determines reconstructed samples for a first coding unit, from the video bitstream, and decodes a dictionary store flag from the video bitstream for the first coding unit. Where the dictionary store flag indicates that reconstructed samples for the first coding unit be stored, the method (i) stores the reconstructed samples for the first coding unit into a memory buffer; (ii) determines reconstructed samples for a second coding unit, the reconstructed samples for the second coding unit being copied from reconstructed samples for the first coding unit from the memory buffer, and (iii) outputs the reconstructed samples for the second coding unit. Also disclosed is a complementary method for encoding, a decoder and an encoder.

Abstract: Disclosed is a method of decoding a luma transform and plurality of chroma transforms from a video bitstream. The chroma transforms contain chroma data for a single colour channel. The method determines a value of a luma transform skip flag for the luma transform indicating whether data of the luma transform is encoded in the video bitstream as a spatial domain representation. A value of a chroma transform skip flag is determined for a first chroma transform of the plurality of chroma transforms indicating whether the data of the chroma transform is encoded in the video bitstream as a spatial domain representation. The method decodes the luma transform according to the determined luma transform skip flag and the plurality of chroma transforms according to the determined chroma transform skip flag for the first chroma transform.

Abstract: Disclosed is a method of decoding a luma transform and plurality of chroma transforms from a video bitstream. The chroma transforms contain chroma data for a single color channel. The method determines a value of a luma transform skip flag for the luma transform indicating whether data of the luma transform is encoded in the video bitstream as a spatial domain representation. A value of a chroma transform skip flag is determined for a first chroma transform of the plurality of chroma transforms indicating whether the data of the chroma transform is encoded in the video bitstream as a spatial domain representation. The method decodes the luma transform according to the determined luma transform skip flag and the plurality of chroma transforms according to the determined chroma transform skip flag for the first chroma transform.

Abstract: A method of decoding a current block encoded using intra-prediction includes determining prediction modes for coding blocks neighboring the current block. The method generates prediction values for edge samples of the decoded block from intra-prediction reference samples of the neighboring coding blocks by applying an intra-prediction process to the intra-prediction encoded current block if a number of the neighboring coding blocks determined to one of use intra-block copy prediction mode and palette mode is greater than or equal to a predetermined threshold. Alternatively the method generates the prediction values for the edge samples of the decoded block from intra-prediction reference samples of the neighboring coding blocks by applying a filter, preferably an intra-boundary filter, to reference samples of the neighboring blocks. The current block is then decoded based on the prediction values.

Abstract: Disclosed is method of decoding, from a video bitstream, a transform unit containing at least one chroma residual coefficient array associated with a single chroma channel. The method determines a size of the transform unit related to a hierarchical level of the transform unit in a corresponding coding unit, and identifies a maximum number of inverse transforms according to the determined size. The method decodes from the video bitstream the at least one chroma residual coefficient array using the identified maximum number of transforms, selects an inverse transform for the decoded chroma residual coefficient arrays, the inverse transform being selected from a predetermined set of inverse transforms, and applies the selected inverse transform to each of the chroma residual coefficient arrays to decode chroma residual samples for the chroma channel of the transform unit. A similar encoding method is also disclosed.

Abstract: A method of encoding a coding tree unit in a video bitstream. A plurality of candidate configurations are formed for the coding tree unit, each of the candidate configurations having a variation of at least one of a set of partitioning modes and encoding parameters. A candidate configuration is selected from the plurality of candidate configurations based on a predetermined maximum bit rate for the coding tree unit, the selected candidate configuration having a size within the predetermined maximum bit rate. The coding tree unit is encoded using the selected candidate configuration.

Abstract: Disclosed is method of decoding, from a video bitstream, a transform unit containing at least one chroma residual coefficient array associated with a single chroma channel. The method determines a size of the transform unit related to a hierarchical level of the transform unit in a corresponding coding unit, and identifies a maximum number of inverse transforms according to the determined size. The method decodes from the video bitstream the at least one chroma residual coefficient array using the identified maximum number of transforms, selects an inverse transform for the decoded chroma residual coefficient arrays, the inverse transform being selected from a predetermined set of inverse transforms, and applies the selected inverse transform to each of the chroma residual coefficient arrays to decode chroma residual samples for the chroma channel of the transform unit. A similar encoding method is also disclosed.

Abstract: Disclosed is a method of decoding residual coefficients of a transform unit from a bitstream of video data. The method receives the transform unit (1500) from the bitstream of video data in which the transform unit has upper (1503) and lower (1502) level square layers. The upper level layer represents a square arrangement of at most four significant coefficient group flags with each of the significant coefficient group flags representing a non-overlapping region of the lower level layer. The method determines determining the significant coefficient group flags of the square upper level layer for the received transform unit, and determines values of residual coefficients of the square lower layer according to the determined significant coefficient group flags to decode the transform unit of the bitstream of video data. Corresponding encoding methods are also disclosed.

Abstract: A method of decoding a bit-stream of encoded video data in a video decoder is disclosed. The method determines if the bit-stream of encoded video data has extended precision processing enabled and has a bit-depth greater than nine bits, when a profile of the bit-stream of the encoded video data is determined to be unsupported by the video decoder. The bit-stream of the encoded video data is decoded to determine decoded video data, using a profile supported by the video decoder, if the bit stream has extended precision processing enabled and a bit depth greater than nine (9) bits. The decoded video data has differences to the video data encoded in the bit-stream due to the unsupported profile being different to the supported profile.

Abstract: Disclosed is a method of decoding a plurality of coding units from a bitstream of video data. The method determines a coding unit structure of the plurality of coding units from a first data block of the bitstream. The coding unit structure describes a division of a coding unit into the plurality of coding units. The method decodes, according to the determined coding unit structure, bypass encoded data for the plurality of coding units from a second data block of the bitstream. The method decodes, according to the determined coding unit structure, residual data for the plurality of coding units from a third data block of the bitstream. The method then forms the plurality of coding units from the bitstream using the residual data and the bypass encoded data. A method of encoding is also disclosed.

Abstract: Disclosed is a method of decoding residual coefficients of a transform unit from a bitstream of video data. The method receives the transform unit (1500) from the bitstream of video data in which the transform unit has upper (1503) and lower (1502) level square layers. The upper level layer represents a square arrangement of at most four significant coefficient group flags with each of the significant coefficient group flags representing a non-overlapping region of the lower level layer. The method determines determining the significant coefficient group flags of the square upper level layer for the received transform unit, and determines values of residual coefficients of the square lower layer according to the determined significant coefficient group flags to decode the transform unit of the bitstream of video data. Corresponding encoding methods are also disclosed.

Abstract: A decoding method of selecting a value for a video parameter based on a portion of video data encoded in a video bitstream. The method receives the portion of encoded video data from the video bitstream and determines an aggregate value based on the received portion of the video data. The method determines a remainder by dividing the aggregate value with a predetermined value and then selects a value for the video parameter from a set of predefined values according to a mapping from the determined remainder, wherein the mapping has at least a plurality of values for a remainder corresponding to a single value for the video parameter. Associated methods for encoding are also disclosed.

Abstract: Disclosed is a method of decoding a plurality of coding units from a bitstream of video data. The method determines a coding unit structure of the plurality of coding units from a first data block of the bitstream. The coding unit structure describes a division of a coding unit into the plurality of coding units. The method decodes, according to the determined coding unit structure, bypass encoded data for the plurality of coding units from a second data block of the bitstream. The method decodes, according to the determined coding unit structure, residual data for the plurality of coding units from a third data block of the bitstream. The method then forms the plurality of coding units from the bitstream using the residual data and the bypass encoded data. A method of encoding is also disclosed.

Abstract: Decoding includes identifying a scan pattern by which the bitstream is decoded. A set index value is decoded from the bitstream that specifies a set of flags according to the scan pattern that contains a last significant coefficient flag of the significance map, and individual significance flags are decoded and the decoded values written into the significance map according to the scan pattern and including the specified set of flags. Encoding a significance map includes identifying a scan pattern by which the significance map is scanned to form a list of significant coefficient flags. Encoding identifies a group of significant coefficient flags including a last significant coefficient flag and referencing the identified group with a scan index value. The significance map is then scanned in accordance with the scan pattern up to and including an entirety of the identified group and the scanned flag values then encoded.