H04N11/02

Resilient image compression and decompression

An image processing method includes selecting an image in fixed storage of a computer and loading the selected image into memory of the computer. The method further includes representing the loaded image by a processor of the computer in the memory as an initial two-dimensional array of pixel values. Thereafter, the initial two-dimensional array of pixel values may be transformed into a hierarchy of progressively axially decremented two-dimensional arrays of signs and a pair of one-dimensional values for each 2×2 array of signs amongst the decremented two-dimensional arrays of signs. Finally, each of the two-dimensional arrays of signs and each pair of one-dimensional values may be stored in the fixed storage as a compressed form of the selected image.

Method and an apparatus for processing a video signal

The present invention relates to a video signal decoding method for adding an intra prediction mode as a sub-macroblock type to prediction of a macroblock in coding a video signal. Some implementations may include obtaining a macroblock type, when a macroblock includes the intra prediction coded sub-macroblock and the inter prediction coded sub-macroblock based on the macroblock type, obtaining prediction mode flag information indicating whether the sub-macroblock is the intra prediction coded or the inter prediction coded, and obtaining a prediction value of the sub-macroblock. Accordingly, implementations disclosed herein may raise coding efficiency of video signal by adding an intra prediction mode as a sub-macroblock type in predicting a macroblock.

Transformations for signal enhancement coding

Measures are provided to encode a signal. An input frame is received and down-sampled to obtain a down-sampled frame. The down-sampled frame is passed to an encoding module which encodes the down-sampled frame to generate an encoded frame. A decoded frame is obtained from a decoding module which generates the decoded frame by decoding the encoded frame. A set of residual data is generated by taking a difference between the decoded frame and the down-sampled frame and is encoded to generate a set of encoded residual data. The encoding comprises transforming the set of residual data into a transformed set of residual data. The set of encoded residual data is output to a decoder to enable the decoder to reconstruct the input frame. Measures are also provided to decode a signal.

Method and device for encoding/decoding motion vector

A motion vector encoding apparatus includes: a predictor configured to obtain motion vector predictor candidates of a plurality of predetermined motion vector resolutions by using a spatial candidate block and a temporal candidate block of a current block, and to determine motion vector predictor of the current block, a motion vector of the current block, and a motion vector resolution of the current block by using the motion vector predictor candidates; and an encoder configured to encode information representing the motion vector predictor of the current block, a residual motion vector between the motion vector of the current block and the motion vector predictor of the current block, and information representing the motion vector resolution of the current block, wherein the plurality of predetermined motion vector resolutions include a resolution of a pixel unit that is greater than a resolution of one-pel unit.

Method and apparatus for video coding
11483551 · 2022-10-25 · ·

Aspects of the disclosure provide a method and an apparatus for video coding. In some examples, the apparatus includes processing circuitry. The processing circuitry decodes prediction information of a current block in a current picture from a coded video bitstream and the prediction information is indicative of inter prediction. The processing circuitry determines, for the current block, motion information including a first motion vector (MV) that has a x component and a y component where each of the x and y components has a fractional MV precision that is 2.sup.−N of a sample size in the current block and has one of 2.sup.L+1 MV values with the fractional MV precision. N is an integer larger than 2 and L is a positive integer. The processing circuitry reconstructs at least one sample of the current block based on the motion information.

Image coding method based on quadratic transform, and apparatus therefor
11483589 · 2022-10-25 · ·

An image decoding method according to the present document comprises the steps of: receiving a quantized transform coefficient for a target block and a transform index for non-separable quadratic transform; deriving transform coefficients by inversely quantizing the quantized transform coefficient; deriving corrected transform coefficients on the basis of a transform kernel matrix in a predetermined transform set indicated by the transform index; and deriving residual samples for the target block on the basis of inverse linear transform for the corrected transform coefficients, wherein when the target block is divided into a predetermined number of sub-blocks and is coded by intra prediction, the corrected transform coefficients are derived in units of the sub-blocks, and the transform index is received for the target block.

Video Coding Device And Method
20230070021 · 2023-03-09 ·

A video encoding method includes (i) determining a current bit rate of a communication channel between a destination device and a source device that stores an input video frame, and (ii) generating a current reconstructed frame and an encoded bitstream at least in part via inter-frame coding of a current input video frame of a sequence of input video frames using a previously-generated reconstructed frame generated at least in part via inter-frame coding of a previous input video frame. The current reconstructed frame is a compressed version of the current input video frame. When both (i) a subsequent bit rate, determined after said inter-frame coding, is less than a threshold and (ii) the current bit rate exceeds the threshold, the method includes: (a) generating a downscaled reconstructed frame at least in part by downscaling the current reconstructed frame; and (b) appending the encoded bitstream with a bit sequence representing the downscaled reconstructed frame.

Methods and apparatus for multi-hypothesis mode reference and constraints
11477474 · 2022-10-18 · ·

The techniques described herein relate to methods, apparatus, and computer readable media configured to decode and/or encode video data. If the current coding block was using more than one hypotheses of prediction data to generate the prediction data, first prediction data is determined for a current coding block of a picture generated using a first prediction mode, and second prediction data is determined for the current coding block generated using a second prediction mode. Information derived from at least one of the first prediction mode and the second prediction mode can be stored. The stored information can be referenced by the subsequent coding blocks.

Spatially varying transform with adaptive transform type

A video decoding method includes determining a usage of an SVT-vertical (V) or an SVT-horizontal (H) for a residual block; determining a transform block position of a transform block of the residual block; determining a transform type of the transform block, wherein the transform type indicates a horizontal transform and a vertical transform for the transform block, wherein at least one of the horizontal transform or the vertical transform is a discrete sine transform (DST)-7; and reconstructing the residual block based on the transform type, the transform block position, and transform coefficients of the transform block.

Inter prediction method and related apparatus

This application provides an example inter prediction method and a related example apparatus. One example method includes parsing a bitstream to determine prediction information of a to-be-processed picture block, where the prediction information indicates that a prediction direction of the to-be-processed picture block is bidirectional prediction, where the bitstream does not include target identification information, and where the target identification information indicates to perform local illumination compensation (LIC) on the to-be-processed picture block; and obtaining a prediction value of the to-be-processed picture block based on the prediction information.