A video signal processing method may include: a step for determining whether a secondary inverse transform is applied to the current block; a step for deriving a secondary transform kernel set which is applied to the current block from among predefined secondary transform kernel sets on the basis of an intra prediction mode of the current block when the secondary inverse transform is applied to the current block; a step for selecting a secondary transform kernel, which is applied to the current block, in the selected secondary transform kernel set; a step for generating a secondary inverse transformed block by performing a secondary inverse transform on a specified upper-left region of the current block by using the secondary transform kernel; and a step for generating a residual block of the current block by performing a primary inverse transform on the secondary inverse transformed block.

An electronic apparatus performs a method of coding video data. The method comprises: receiving, from the bitstream, the video data corresponding to a coding unit, wherein the coding unit is coded by intra-prediction mode or inter-prediction mode; receiving a first syntax element from the video data, wherein the first syntax element indicates whether the coding unit has been coded using adaptive color-space transform (ACT); processing the video data to generate residuals of the coding unit; in accordance with a determination based on the first syntax element that the coding unit has been coded using the ACT, performing a clipping operation that confines a dynamic range of the residuals of the coding unit within a predefined range; and applying an inverse ACT to the residuals of the coding unit after the clipping operation.

Methods, apparatus, and computer readable storage medium for processing video data. The method includes extracting a data block from the video data; scanning a first number of data items in the data block following a first scan order to generate a first data sequence; performing a non-separable transform to the first data sequence to obtain a second data sequence having a second number of data items; and replacing at least a portion of the first number of data items in the data block with a portion or all of the second data sequence following a second scan order.

An apparatus for block-wise decoding a picture from a data stream and/or encoding a picture into a data stream, the apparatus supporting at least one intra-prediction mode according to which the intra-prediction signal for a block of a predetermined size of the picture is determined by applying a first template of samples which neighbours the current block onto a neural network. The apparatus may be configured, for a current block differing from the predetermined size, to: resample a second template of samples neighboring the current block, so as to conform with the first template so as to obtain a resampled template; apply the resampled template of samples onto the neural network so as to obtain a preliminary intra-prediction signal; and resample the preliminary intra-prediction signal so as to conform with the current block so as to obtain the intra-prediction signal for the current block.

An image decoding method performed by a decoding apparatus according to the present disclosure includes receiving a bitstream including residual information; deriving quantized transform coefficients for a current block based on the residual information included in the bitstream; deriving residual samples for the current block based on the quantized transform coefficients; and generating a reconstructed picture based on the residual samples for the current block.

An image decoding device (200) includes: an inverse transform unit (220B/220C) configured to generate a prediction residual signal by inverse transform, the inverse transform unit (220B/220C) is configured to control a method of decoding a secondary transform index of a target block according to information indicating a position where a non-zero coefficient is generated in the target block.

A method of video encoding includes determining whether a first block associated with a second block is to be predicted according to a block differential pulse code modulation (BDPCM) mode, and, in response to determining that the first block is to be predicted according to the BDPCM mode, associating the first block with an intra prediction mode value based on a BDPCM direction for the first block. The intra prediction mode value is selected from a plurality of intra prediction modes that include angular intra prediction modes. The method also includes determining an intra prediction mode value for the second block using the intra prediction mode value associated with the first block, and encoding the second block using the determined intra prediction mode value for the second block.

A video signal processing device includes a processor. The processor is configured to obtain a secondary transform kernel for a current block based on an intra prediction mode of the current block to which a secondary transform is applied, to obtain a secondary inverse transformed block by performing a secondary inverse transform on a top-left specific region of the current block using the secondary transform kernel, wherein the secondary inverse transform is an inverse transform of the secondary transform, and the secondary transform is a low frequency non-separable transform, to obtain a residual block of the current block by performing a primary inverse transform on the secondary inverse transformed block, wherein one or more coefficients of the top-left specific region of the current block are derived in a preset scan order and the preset scan order is a 4×4 up-right diagonal scan order regardless of a size of the current block.

A super-resolution coding mode is described. An encoded image can be decoded from an encoded bitstream stored on a non-transitory computer-readable storage medium. A flag can indicate whether an image was encoded using the super-resolution mode at a first resolution. Responsive to the flag indicating that the image was encoded using the super-resolution mode, bits indicating an amount of scaling of the image are included. The image is decoded from the encoded bitstream to obtain a reconstructed image at the first resolution, and the reconstructed image is upscaled to a second resolution using the amount of scaling to obtain an upscaled reconstructed image. The second resolution is higher than the first resolution. Loop restoration parameters within the bitstream can used for look restoration filtering of the upscaled reconstructed image to obtain a loop restored image at the second resolution.

The present specification discloses a method of decoding an image. The method of decoding an image according to the method includes: obtaining transform skip information of a current block from a bitstream; obtaining multiple transform selection information of the current block on the basis of the transform skip information from the bitstream; and performing inverse transform on the current block on the basis of the multiple transform selection information, wherein the multiple transform selection information is used to set each of a horizontal transform type and a vertical transform type.