Several systems, methods and integrated circuits capable of reducing blocking artifacts in video data are disclosed. In an embodiment, a system for reducing blocking artifacts in video data includes a processing module and a deblocking module. The deblocking module comprises a luma deblocking filter and a chroma deblocking filter configured to filter an edge between adjacent blocks associated with the video data, where a block of the adjacent blocks corresponds to one of a prediction block and a transform block. The processing module is communicatively associated with the deblocking module and is operable to configure at least one filter coefficient corresponding to the chroma deblocking filter based on one or more filter coefficients corresponding to the luma deblocking filter. The processing module is further configured to cause the chroma deblocking filter to filter the edge between the adjacent blocks based on the configured at least one filter coefficient.

A method for adaptive MV precision is disclosed. According to one embodiment, whether to use or not to use the adaptive MV precision for a current block is determined according to a prediction mode/partition type of the current block. If the adaptive MV precision is used, a current MV precision is determined for a current MV of the current block, and the current MV is encoded or decoded at the current MV precision. If the adaptive MV precision is not used, the current MV is encoded or decoded at a finer MV precision. In another embodiment, a value of a current adaptive MV precision flag is selected for a current block to indicate whether to use or not to use the adaptive MV precision for a current block according to a prediction mode/partition type of the current block.

A method for adaptive MV precision is disclosed. According to one embodiment, whether to use or not to use the adaptive MV precision for a current block is determined according to a prediction mode/partition type of the current block. If the adaptive MV precision is used, a current MV precision is determined for a current MV of the current block, and the current MV is encoded or decoded at the current MV precision. If the adaptive MV precision is not used, the current MV is encoded or decoded at a finer MV precision. In another embodiment, a value of a current adaptive MV precision flag is selected for a current block to indicate whether to use or not to use the adaptive MV precision for a current block according to a prediction mode/partition type of the current block.

A video decoding method performed by a decoding apparatus according to the present disclosure includes deriving one of a plurality of cross-component linear model (CCLM) prediction mode as a CCLM prediction mode of the current chroma block, deriving a sample number of neighboring chroma samples of the current chroma block based on the CCLM prediction mode of the current chroma block, a size of the current chroma block, and a specific value; deriving the neighboring chroma samples of the sample number, calculating CCLM parameters based on the neighboring chroma samples and the down sampled neighboring luma samples, deriving prediction samples for the current chroma block based on the CCLM parameters and the down sampled luma samples and generating reconstructed samples for the current chroma block based on the prediction samples, wherein the specific value is derived as 2.

Video decoder and/or video encoder, configured to determine a set of search area location candidates in a reference picture of a video; match the set of search area location candidates with a current template area adjacent to a current block of a current picture to obtain a best matching search area location candidate; select, out of a search area positioned in the reference picture at the best matching search area location candidate, a set of one or more predictor blocks by matching the current template area against the search area; and predictively decode/encode the current block from/into a data stream based on the set of one or more predictor blocks.

A method includes performing a conversion between a video including at least one video picture and a bitstream of the video according to a rule, wherein the at least one video picture includes one or more slices and one or more subpictures, and wherein the rule specifies that an order of slice indices of the one or more slices in the at least one video picture is indicated responsive to a syntax element associated with the at least one picture indicative of whether a single slice is included per subpicture of the at least one video picture.

A method includes performing a conversion between a video including at least one video picture and a bitstream of the video according to a rule, wherein the at least one video picture includes one or more slices and one or more subpictures, and wherein the rule specifies that an order of slice indices of the one or more slices in the at least one video picture is indicated responsive to a syntax element associated with the at least one picture indicative of whether a single slice is included per subpicture of the at least one video picture.

An example method includes inferring, for a current transform block of a current video block, a transform type from a plurality of transform types that includes one or more discrete cosine transforms (DCTs) and one or more discrete sine transforms (DSTs), wherein inferring the transform type comprises: determining a size of the current transform block; determining whether the current video block is partitioned using intra-subblock partitioning (ISP); and responsive to determining that the size of the current transform block is less than a threshold and that the current video block is partitioned using ISP, selecting a particular DST of the one or more DSTs as the selected transform type; transforming, using the selected transform type, the current transform block to obtain a block of reconstructed residual data for the video block; and reconstructing, based on the reconstructed residual data for the video block, the video block.

An image coding method includes: writing, into a sequence parameter set, buffer description defining information for defining a plurality of buffer descriptions; writing, into the sequence parameter set, reference list description defining information for defining a plurality of reference list descriptions corresponding to the buffer descriptions; and writing, into a first header of each processing unit which is included in a coded bitstream, buffer description selecting information for specifying a selected buffer description.

An image coding method includes: writing, into a sequence parameter set, buffer description defining information for defining a plurality of buffer descriptions; writing, into the sequence parameter set, reference list description defining information for defining a plurality of reference list descriptions corresponding to the buffer descriptions; and writing, into a first header of each processing unit which is included in a coded bitstream, buffer description selecting information for specifying a selected buffer description.