A method by which a decoding device decodes an image, according to the present document, comprises the steps of: acquiring prediction-related information about the current block; acquiring residual information about the current block; deriving a prediction sample of the current block on the basis of the prediction-related information; deriving a residual sample of the current block on the basis of the residual information; and generating a reconstructed picture on the basis of the prediction sample and the residual sample.

Methods, apparatus, systems, and articles of manufacture are disclosed to implement predictor prefetching in video encoding. The example apparatus includes processor circuitry to perform operations to instantiate a predictor list generator circuitry and a predictor prefetch circuitry. The example predictor list generator circuitry to obtain predictor candidates indicating memory locations storing reference blocks from a previous block and sort the predictor candidates in a priority order. The example predictor prefetch circuitry to send cache line requests to the memory corresponding to at least some the predictor candidates that satisfy a threshold priority value. The example predictor prefetch circuitry to send the cache line requests to the memory before a reference block winner of the previous block is determined.

A method of decoding a bitstream by an electronic device is provided. The electronic device receives the bitstream. In addition, the electronic device determines a block unit from an image frame according to the bitstream and determines a linear model prediction mode of the block unit based on a plurality of linear mode candidates. The plurality of linear mode candidates is used to derive a plurality of linear model formulas based on a plurality of sample sets determined from a common reference region. The electronic device further reconstructs the block unit based on the linear model prediction mode

A method of decoding a bitstream by an electronic device is provided. The electronic device receives the bitstream. In addition, the electronic device determines a block unit from an image frame according to the bitstream and determines a linear model prediction mode of the block unit based on a plurality of linear mode candidates. The plurality of linear mode candidates is used to derive a plurality of linear model formulas based on a plurality of sample sets determined from a common reference region. The electronic device further reconstructs the block unit based on the linear model prediction mode

In an example, a method of decoding video data includes generating a residual block of a picture based on a predicted residual block including reconstructing one or more residual values of the residual block based on one or more predicted residual values of the residual block. The method also includes generating a current block of the picture based on a combination of the residual block and a prediction block of the picture.

In an example, a method of decoding video data includes generating a residual block of a picture based on a predicted residual block including reconstructing one or more residual values of the residual block based on one or more predicted residual values of the residual block. The method also includes generating a current block of the picture based on a combination of the residual block and a prediction block of the picture.

A method of signing prediction-coded video data, comprising: obtaining a coded video sequence including at least one I-frame (I), which contains independently decodable image data, and at least one predicted frame (P1, P2, P3, P4), which contains image data decodable by reference to at least one other frame; generating a fingerprint (H.sub.I) of each I-frame; generating a fingerprint (H.sub.P) of each predicted frame by hashing a combination of data derived from the predicted frame and data derived from an I-frame to which the predicted frame refers directly or indirectly, wherein the fingerprint of the predicted frame is independent of any further predicted frame to which the predicted frame refers directly or indirectly; and providing a signature of the video sequence including the generated fingerprints.

A method of signing prediction-coded video data, comprising: obtaining a coded video sequence including at least one I-frame (I), which contains independently decodable image data, and at least one predicted frame (P1, P2, P3, P4), which contains image data decodable by reference to at least one other frame; generating a fingerprint (H.sub.I) of each I-frame; generating a fingerprint (H.sub.P) of each predicted frame by hashing a combination of data derived from the predicted frame and data derived from an I-frame to which the predicted frame refers directly or indirectly, wherein the fingerprint of the predicted frame is independent of any further predicted frame to which the predicted frame refers directly or indirectly; and providing a signature of the video sequence including the generated fingerprints.

Methods, systems and apparatus for video processing are described. One example video processing method includes performing a conversion between a video comprising a video block and a bitstream of the video according to a rule, wherein the video block is a coding tree node that includes one or more coding units, and wherein the rule specifies that a coded information of the video block is indicative of whether a coding mode is enabled for the one or more coding units of the video block.

A macro block size determining unit 1 determines the size of each macro block on a frame-by-frame basis. A macro block dividing unit 2 divides an inputted image into macro blocks each having the size determined by the macro block size determining unit 1. A macro block coding unit 3 determines a coding mode for each of the macro blocks divided by the macro block dividing unit 2, and codes pixel values in each of the macro blocks in the determined coding mode.