Abstract: A method, decoder apparatus, and computer programs are provided. A bit stream having a video block encoded with a multiple transform selection (MTS) index is received. The MTS index is parsed to determine a value of it. Responsive to the MTS index value being a predetermined value (or one of a predetermined set of indices), a LFNST index is parsed from the bit stream to determine a value of it, the value providing an indication whether a LFNST transform set is to be used in decoding the video block. Responsive to the MTS index value not being the predetermined value (or one of the set of indices), the value of the LFNST index is set to a default value indicating no LFNST transform is to be used in the decoding. The video block is decoded based on the values of the MTS index and the LFNST index.

Abstract: A method, decoder, and apparatus are provided. Responsive to a current block being a MIP predicted block, it is determined whether it has one or multiple transform blocks. A MIP weight matrix to be used to decode the current block is determined based on a MIP prediction mode. Responsive to the MIP predicted block having one transform block, the MIP predicted block is derived based on the MIP weight matrix and previously decoded elements in the bitstream. Responsive to the MIP predicted block having multiple transform blocks: deriving a first MIP predicted block is derived based on the MIP weight matrix and previously decoded elements in the bitstream and remaining MIP predicted blocks are derived based further on decoded elements in at least one decoded transform block of the current block. The MIP predicted block(s) are output for subsequent processing.

Abstract: Methods and devices for determining video picture resolution. A first source picture is obtained and a first reduced resolution picture is generated based on the first source picture. A first similarity metric is determined for the first reduced resolution picture and the first source picture. A picture resolution is selected based at least in part on the first similarity metric.

Abstract: There is provided a method of encoding a picture. The method comprises selecting a motion vector. MV, for a current block within the picture. The method comprises determining whether a condition is satisfied, wherein determining whether the condition is satisfied comprises: (i) determining if a subblock-based motion refinement is applicable for the current block and (ii) determining if a first subblock within the current block satisfies a criteria. The method comprises, as a result of determining that the condition is satisfied, not using the selected MV for encoding the current block.

Abstract: Methods and apparatuses for applying a deblocking to a coding unit in video pictures a provided. In one aspect, the deblocking is applied to sub-block boundaries in the coding unit and to implicit transform unit boundaries in the coding unit.

Abstract: A method for encoding or decoding an image. The method includes obtaining a coding tree block (CTB) having a vertical size (CtbSizeY) and a horizontal size (CtbSizex), the CTB comprising set of sample values associated with the image, the set of sample values comprising a current sample value having a location (x,y) within the CTB, where x is a horizontal value and y is a vertical value. The method also includes selecting a filter strength value for the current sample based on y and filtering the current sample using the selected filter strength value. Selecting a filter strength value for the current sample based on y comprises: i) determining whether the following first condition is true: (y==(CtbSizeY?5) OR y==(CtbSizeY?4)) AND var==1, where var is a variable that is set equal to 1 as a result of a determination that a second condition is satisfied; and ii) choosing a filter strength value of 10 as a result of determining that the first condition is true.

Abstract: There is provided a method, performed by a temporal filter. The method comprises obtaining a current picture and a set of one or more neighbor pictures comprising a first neighbor picture, wherein each of the one or more neighbor pictures either precedes or follows the current picture in a picture count order. The method comprises, based on a first block of pixel values of the current picture and a first block of pixel values in the first neighbor picture, determining a first filter weight, W1, for at least a first pixel value in the first block of pixel values of the current picture, wherein the first block of pixel values in the first neighbor picture correspond to the first block of pixel values in the current picture.

Abstract: A prediction unit for an encoder or decoder implements matrix based intra prediction. Input boundary samples for a current block are downsampled to obtain reduced boundary samples for matrix multiplication and/or linear interpolation, or both. In one embodiment, downsampling is performed in a manner that aligns the reduced boundary samples with an output of a matrix multiplication unit of the prediction unit. In other embodiments, downsampling is performed without averaging. The embodiments reduce the complexity of the prediction unit and the latency of the encoder or decoder.

Abstract: There are provided mechanisms for methods and apparatuses for transform selection in encoding and decoding of video blocks.

Abstract: In one aspect there is disclosed a method of applying deblocking on implicit vertical TU boundaries when the CU width is larger than the maximum TU width and applying deblocking on implicit horizontal TU boundaries when the CU height is larger than the maximum TU height. Some exemplary embodiments include HEVC deblocking and deblocking using longer filters.

Abstract: A method for decoding a current block in a current picture of a video bitstream includes decoding, from the video bitstream, a first motion vector for the current block relative to a first reference block of a first reference picture having a first picture order count, and decoding, from the video bitstream, a second motion vector for the current block relative to a second reference block of a second reference picture having a second picture order count. A similarity metric is generated based on a comparison of the first motion vector and the second motion vector. The method further includes determining whether to refine the first motion vector based on the similarity metric, generating a first refined motion vector from the first motion vector, and performing motion compensation to derive a first reference block from the first reference picture using the first refined motion vector.

Abstract: Methods and apparatus for encoding or decoding a first structure within a picture in a video sequence are provided. The method comprises, for a second structure within the first structure, determining an initial motion vector, MV, and MV candidates. The method comprises, for each of the MV candidates, using the MV candidate to derive first and second reference blocks, and a size of the first and second reference blocks may not be equal to a size of the second structure. The method comprises deriving a cost value based on samples from the first and second reference blocks. The method comprises using the cost values from the MV candidates to derive a best MV candidate and using the best MV candidate to derive prediction samples for the second structure.

Abstract: A method performed by an apparatus to determine compression parameters to choose when compressing images or videos for use in a machine vision task is provided. The method includes compressing an uncompressed original image or video at a plurality of different quality levels and/or bit rates to create a plurality of compressed images or videos. The method further includes, for each compressed image or video compressed at the different quality levels and/or bit rates: decompressing the compressed image or video to create a decompressed image or video, executing a machine vision algorithm on the decompressed image or video to generate machine vision results for the decompressed image or video and deriving a performance value indicating a performance of the decompressed image or video based on comparing the machine vision results to an assumed truth.

Abstract: A method for decoding a picture from a bitstream. The method includes decoding a tile partition structure from one or more syntax elements in the bitstream. The method includes determining a number of tiles N in the picture. The method includes decoding a number of partitions in the picture, wherein each partition comprises an integer number of tiles. The method includes deriving a size and/or location for a current partition, wherein deriving the size and/or location for the current partition comprises: decoding one or more location syntax elements for the current partition from the bitstream, deriving a top-left position of the current partition as a location of a first tile in raster scan order that is not included in one or more previously derived partition, and deriving the size and/or the location of the current partition from a value of the one or more location syntax element together with a size and/or location of the one or more previously derived partition.

Abstract: The present embodiments introduce a new type of random access point in video bitstreams that can be used for random access operations but can be represented in encoded form at a lower bit-cost as compared to IRAP pictures. The random access point is a dependent random access point (DRAP) picture that is encoded and decoded using an IRAP picture and/or a previous, according to a decoding order, DRAP picture as sole reference picture(s) for the DRAP picture. The DRAP picture is encoded as a trailing picture that may be used for reference and constitutes a random access point in a video bitstream.

Abstract: There are provided mechanisms for methods and apparatuses for transform selection in encoding and decoding of video blocks.

Abstract: There is provided a method for encoding one or more images. The method comprises filtering, with a first filter, input samples I(x,y) to generate a first filtered output Ifirst(x,y)=I(x,y)+?Ifirst(x,y). The method comprises estimating parameters for a second filter based at least in part on the first filtered output Ifirst(x,y), the input samples I(x,y), and original samples Iorig(x,y). The method comprises filtering, with the second filter, input samples I(x,y) to generate a second filtered output Isecond(x,y)=I(x,y)+?Isecond(x,y), wherein filtering, with the second filter, is based at least in part on the parameters estimated for the second filter. The method comprises generating a combined output ICOMB(x,y)=I(x,y)+?Ifirst(x,y)+?Isecond(x,y).

Abstract: A prediction unit (60) for an encoder (24) or decoder (44) implements matrix based intra prediction Input boundary samples for a current block are downsampled to obtain reduced boundary samples for matrix multiplication and/or linear interpolation, or both. In one embodiment, downsampling is performed in a manner that aligns the reduced boundary samples with an output of a matrix multiplication unit of the prediction unit. In other embodiments, downsampling is performed without averaging. The embodiments reduce the complexity of the prediction unit and the latency of the encoder (24) or decoder (44).

Abstract: There is provided a method for encoding a picture. The method comprises, for each picture on either side of the current picture with a distance of one or two away from the current picture, computing a first error value, E, wherein the first error value, E, is computed for each block of a set of blocks of a first block size of the current picture and is based on the respective block of the current picture and a corresponding block in the picture. The method comprises, for each picture on either side of the current picture with a distance of one or two away from the current picture, aggregating the first error value, E, over a block of a second block size for each block of the set of blocks of the first block size contained in the block of the second block size to generate a second error value, E?, corresponding to the picture.

Abstract: A method, decoder, and apparatus are provided. Responsive to a current block being a MIP predicted block, it is determined whether it has one or multiple transform blocks. A MIP weight matrix to be used to decode the current block is determined based on a MIP prediction mode. Responsive to the MIP predicted block having one transform block, the MIP predicted block is derived based on the MIP weight matrix and previously decoded elements in the bitstream. Responsive to the MIP predicted block having multiple transform blocks: deriving a first MIP predicted block is derived based on the MIP weight matrix and previously decoded elements in the bitstream and remaining MIP predicted blocks are derived based further on decoded elements in at least one decoded transform block of the current block. The MIP predicted block(s) are output for subsequent processing.