Patent classifications
H04N19/197
INTRA PREDICTION METHOD AND APPARATUS IN IMAGE CODING SYSTEM
An image decoding method performed by a decoding apparatus according to the present disclosure comprises the steps of: obtaining a reference sample line index of a current block and most probable mode (MPM)-related information; constructing an alternative MPM list on the basis of the reference sample line index; deriving an intra prediction mode of the current block on the basis of the alternative MPM list and the MPM-related information; and generating a predicted block of the current block on the basis of the intra prediction mode, wherein the alternative MPM list is constructed on the basis of an intra prediction mode of an upper adjacent block of the current block and an intra prediction mode of a left adjacent block of the current block.
REGION MERGING AND CODING PARAMETER REUSE VIA MERGING
A favorable merging or grouping of simply connected regions into which the array of information samples is sub-divided, is coded with a reduced amount of data. To this end, a predetermined relative locational relationship is defined enabling an identifying, for a predetermined simply connected region, of simply connected regions within the plurality of simply connected regions which have the predetermined relative locational relationship to the predetermined simply connected region. Namely, if the number is zero, a merge indicator for the predetermined simply connected region may be absent within the data stream. In other embodiments, spatial sub-division is preformed depending on a first subset of syntax elements, followed by combining spatially neighboring simply connected regions depending on a second subset of syntax elements, to obtain an intermediate sub-division.
IMAGE CODING METHOD, IMAGE CODING APPARATUS, IMAGE DECODING METHOD, IMAGE DECODING APPARATUS, AND IMAGE CODING AND DECODING APPARATUS
A method for transmitting a bitstream via a network is provided. The bitstream is for coding a current block and is generated by: deriving a first candidate from a first motion vector that has been used to code a first block; coding a first index identifying a reference picture to be used for coding the current block; deriving a second candidate having a second motion vector that includes a non-zero value, which is assigned to the reference picture; and coding a second index identifying a selected candidate to be used for coding the current block. The second motion vector is not derived by coding a block adjacent to the current block, and the non-zero value is assigned by offset values which include an OffsetX and an OffsetY and which are located in a picture header.
Conditional Signaling Of Syntax Elements In A Picture Header
A video processing method includes performing a conversion between a video including one or more pictures and a bitstream of the video. The bitstream conforms to a format rule specifying that one or more syntax elements indicative of coding information are selectively included in a picture parameter set of the bitstream responsive to whether it is indicated that each picture referring to the picture parameter set includes a single slice.
GENERATING QUANTIZATION TABLES FOR IMAGE COMPRESSION
Methods, systems, and computer programs encoded on a computer storage medium, that relate to generating quantization tables that are used during digital image compression of a digital image. Multiple training images are obtained. A model can be trained using the training images to generate a quantization table that can be used during encoding of an input image. For each training image, a quantization table can be obtained using the model. Using the quantization table, an encoded digital image is obtained for the training image. Using the encoded digital image and the training image, an image quality loss and a compression loss can be determined. An overall loss of the model can be determined by combining the image quality loss and the compression loss for the training image. The model can be updated based on the overall loss.
Method and apparatus for combined intra prediction modes
Encoders and decoders of digital video signals use combined intra prediction modes for some images. In at least one embodiment, combined intra prediction modes can result from the intra prediction modes of neighboring blocks. The combined intra prediction mode can be added to a most probable modes list. Various embodiments describe techniques for combining the intra prediction modes, comprising a combination of reference samples and a combination of directions to form a prediction. Another embodiment adds a combination mode to the most probable modes list if the two modes that are combined to form it are directional modes with angle difference less than 90 degrees. Another embodiment uses a linear combination of intra prediction modes and another embodiment performs a linear combination which depends on the distance of a prediction from the left and above blocs.
Optimized multipass encoding
An original input video file is encoded using a machine learning approach. The encoder performs a detailed video analysis and selection of encoding parameters that using a machine learning algorithm improves over time. The encoding process is done using a multi-pass approach. During a first pass, the entire video file is scanned to extract video property information that does not require in-depth analyses. The extracted data is then entered into an encoding engine, which uses artificial intelligence to produce optimized encoder settings. The video file is into a set of time-based chunks and, in a second pass, the encoding parameters for each chunk are set and distributed to encoding nodes for parallel processing. These encoder instances probe-encode each chunk determine the level of complexity for the chunk and to derive chunk-specific encoding parameters. Following completion of the second pass, the results of both passes are then merged to obtain the necessary information for the encoder to achieve the best possible result.
IMAGE DECODING METHOD AND DEVICE THEREOF
An image decoding method performed by a decoding device according to the present document comprises the steps of: acquiring a block-based delta pulse code modulation (BDPCM) flag for a current block; on the basis of the BDPCM flag indicating that BDPCM is applied to the current block, acquiring a BDPCM direction flag for the current block; and storing, as an intra-prediction mode of the current block, an intra-prediction mode of a prediction direction derived on the basis of the BDPCM direction flag.
NEAREST NEIGHBOR SEARCH METHOD, APPARATUS, DEVICE, AND STORAGE MEDIUM
Described is a nearest neighbor search method. The method is applicable in a device and comprises: acquiring a Morton code set of point cloud data to be searched; stratifying the point cloud data on the basis of the Morton code set and of a first distance threshold to produce current stratum data; shifting to the right by a first preset digit Morton codes of prediction data other than the stratified data in the point cloud data to produce a corresponding first parent node set; determining, on the basis of Morton codes of the current stratum data, a neighbor area satisfying a criterion in the first parent node set; and determining a nearest neighboring point set of the current stratum data in the neighboring area. Also provided in an exemplary embodiment of the present application are a device and a computer storage medium.
Template matching for JVET intra prediction
A method of decoding JVET video, comprising defining a coding unit (CU) template within a decoded area of a video frame, the CU template being positioned above and/or to the left of a current decoding position for which data was intra predicted, defining a search window within the decoded area, the search window being adjacent to the CU template, generating a plurality of candidate prediction templates based on pixel values in the search window, each of the plurality of candidate prediction templates being generated using different intra prediction modes, calculating a matching cost between the CU template and each of the plurality of candidate prediction templates, selecting an intra prediction mode that generated the candidate prediction template that had the lowest matching cost relative to the CU template, and generating a prediction CU for the current decoding position based on the intra prediction mode.