Disclosed herein are a video processing method, apparatus and storage medium using the resolution of a reference picture. Filtering is performed based on resolutions of reference pictures of blocks forming a boundary. The resolutions of the reference pictures may define filtering. Depending on whether the resolutions of the reference pictures are different from each other, one or more filter selection parameters for filtering may be determined or updated. Further, based on whether the resolutions of the reference pictures are different from each other, the boundary strength of the filter may be determined. Because filtering is defined using the resolutions of reference pictures, performance of encoding and/or decoding may be improved.

A method includes performing a conversion between a video that includes at least a video tile and a bitstream of the video according to a rule. The rule specifies that a height of a slice in the video tile in units of coding tree units is derived based on a value of a first syntax element in the bitstream indicating a number of explicitly provided slice heights for slices in the video tile that includes the slice.

Non-transform blocks of video content may be coded by selectively changing a scanning order. In some implementations, an encoder or decoder may perform a scanning process on a block according to a scanning order. When the block has not been transformed, the encoder or decoder may selectively change the scanning order to a different order. For example, if the block is associated with a particular type of prediction, the scanning order may be changed to a different order. In another example, if the non-transform block has a size that is smaller than a predetermined size, the scanning order may be changed to a different order.

Non-transform blocks of video content may be coded by selectively changing a scanning order. In some implementations, an encoder or decoder may perform a scanning process on a block according to a scanning order. When the block has not been transformed, the encoder or decoder may selectively change the scanning order to a different order. For example, if the block is associated with a particular type of prediction, the scanning order may be changed to a different order. In another example, if the non-transform block has a size that is smaller than a predetermined size, the scanning order may be changed to a different order.

According to the disclosure of this document, it is possible to signal information related to a chroma quantization parameter offset through a palette coding syntax, and to efficiently parse and signal index information for a chroma quantization parameter offset list on the basis of information about the number of entries in the chroma quantization parameter offset list. Accordingly, bits that need to be signaled for video/image coding can be reduced, and coding efficiency can be improved.

An image decoding method according to the present document comprises the steps of: determining whether or not an effective coefficient is present in a second area not including an upper-left first area of a current block; parsing an MTS index from a bitstream on the basis that the effective coefficient is not present in the second area; and deriving residual samples for the current block by applying a transform kernel, which is derived on the basis of the MTS index, to transform coefficients in the first area, wherein the MTS index can be parsed on the basis that the effective coefficient, which is present in a scan sub-block which is scanned for the effective coefficient, is not present in the second area.

Embodiments of the present invention provide a video signal processing method and device. Particularly, a method for decoding a video signal, may comprise the steps of: checking whether a transfer skip is applied to a current block; obtaining, from a video signal, a transform index for indicating a transform type set applied to the current block when the transform skip is not applied to the current block, wherein the transform type set includes transform types applied to the current block in horizontal and vertical directions; checking whether the transform type set includes DCT2; determining a region to which a primary transform is applied based on a checking result; and performing an inverse transform on the region to which the primary transform is applied in the horizontal and vertical directions using the transform types included in the transform type set.

Embodiments of the present invention provide a video signal processing method and device. Particularly, a method for decoding a video signal, may comprise the steps of: checking whether a transfer skip is applied to a current block; obtaining, from a video signal, a transform index for indicating a transform type set applied to the current block when the transform skip is not applied to the current block, wherein the transform type set includes transform types applied to the current block in horizontal and vertical directions; checking whether the transform type set includes DCT2; determining a region to which a primary transform is applied based on a checking result; and performing an inverse transform on the region to which the primary transform is applied in the horizontal and vertical directions using the transform types included in the transform type set.

Decoding a coding unit of a coding tree from a coding tree unit, the coding unit having a luma colour channel and at least one chroma colour channel. Decoding a luma transform skip flag for a luma transform block; decoding at least one chroma transform skip flag, each chroma transform skip flag corresponding to one of at least one chroma transform block; determining a secondary transform index by decoding a secondary transform index if at least one of the luma transform skip flag and the at least one chroma transform skip flags indicates that a transform of the transform block is not to be skipped, and determining the secondary transform index to indicate that a secondary transform is not to be applied if all of the luma transform skip flag and the at least one chroma transform skip flags indicate transforms of the respective transform blocks are to be skipped.

An encoder includes circuitry and memory coupled to the circuitry. The circuitry: executes a second process of applying a second filter to the first image to generate a second image, not holding the second image as a reference image, holding the first image as a reference image, and displaying the second image; writes coefficients of each of one or more filter candidates that are candidates for the second filter into a bitstream, wherein the coefficients are included in a first storage location when written into the bitstream; and writes a parameter that specifies, for each image, one of the one or more filter candidates as the second filter into the bitstream, wherein the parameter is included in a second storage location when written into the bitstream, and the second storage location is different from the first storage location.