# US 2024/0205441 A1 · Image decoding device, image decoding method, and program > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2024/0205441 A1 - Document ID: US20240205441A1 - Status: Published application - Kind: A1 - Application number: 18/591,270 - Filed: 2024-02-29 - Published: 2024-06-20 - Earliest claimed: 2022-04-12 - Assignees: Kddi Corporation - Applicants: Kddi Corporation - Inventors: Haruhisa KATO; Yoshitaka KIDANI - Web page: https://patentgrep.com/patent/US20240205441A1 ## CPC - H04N 19/44: Decoders specially adapted therefor, e.g. video decoders which are asymmetric with respect to the encoder - H04N 19/105: Selection of the reference unit for prediction within a chosen coding or prediction mode, e.g. adaptive choice of position and number of pixels used for prediction - H04N 19/124: Quantisation - H04N 19/132: Sampling, masking or truncation of coding units, e.g. adaptive resampling, frame skipping, frame interpolation or high-frequency transform coefficient masking - H04N 19/134: characterised by the element, parameter or criterion affecting or controlling the adaptive coding - H04N 19/136: Incoming video signal characteristics or properties - H04N 19/139: Analysis of motion vectors, e.g. their magnitude, direction, variance or reliability - H04N 19/157: Assigned coding mode, i.e. the coding mode being predefined or preselected to be further used for selection of another element or parameter - H04N 19/176: the region being a block, e.g. a macroblock - H04N 19/18: the unit being a set of transform coefficients - H04N 19/196: being specially adapted for the computation of encoding parameters, e.g. by averaging previously computed encoding parameters (processing of motion vectors H04N19/513) - H04N 19/463: by compressing encoding parameters before transmission - H04N 19/50: using predictive coding (H04N19/61 takes precedence) - H04N 19/51: Motion estimation or motion compensation - H04N 19/593: involving spatial prediction techniques - H04N 19/61: in combination with predictive coding - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION ## Abstract In an image decoding device according to the present invention, a circuit: decodes control information and a quantized value; obtains a decoded transform coefficient by performing inverse quantization on the decoded quantized value; obtains a decoded prediction residual by performing inverse transform on the decoded transform coefficient; generates a first predicted sample based on a decoded sample and the decoded control information; accumulates the decoded sample; generates a second predicted sample based on the accumulated decoded sample and the decoded control information; generates a third predicted sample by weighted averaging using one of weighting coefficients limited based on the decoded control information for at least one of the first predicted sample or the second predicted sample; and obtains the decoded sample by adding the decoded prediction residual and the third predicted sample. ## Claims ### Claim 1 An image decoding device comprising a circuit, wherein the circuit: decodes control information and a quantized value; obtains a decoded transform coefficient by performing inverse quantization on the decoded quantized value; obtains a decoded prediction residual by performing inverse transform on the decoded transform coefficient; generates a first predicted sample based on a decoded sample and the decoded control information; accumulates the decoded sample; generates a second predicted sample based on the accumulated decoded sample and the decoded control information; generates a third predicted sample by weighted averaging using one of weighting coefficients limited based on the decoded control information for at least one of the first predicted sample or the second predicted sample; and obtains the decoded sample by adding the decoded prediction residual and the third predicted sample. ### Claim 2 (depends on 1) The image decoding device according to claim 1, wherein the circuit prepares the plurality of weighting coefficients by which a width of a division boundary of a small area is different and selects the weighting coefficients. ### Claim 3 (depends on 1) The image decoding device according to claim 1, wherein the circuit limits combinations of the selectable weighting coefficients according to a shape of a decoding target block. ### Claim 4 (depends on 3) The image decoding device according to claim 3, wherein the circuit limits combinations of the selectable weighting coefficients according to at least one of a short side of the decoding target block, a long side of the decoding target block, an aspect ratio of the decoding target block, a division mode of the decoding target block, or the number of samples of the decoding target block. ### Claim 5 (depends on 1) The image decoding device according to claim 1, wherein the circuit limits combinations of the selectable weighting coefficients according to a motion vector. ### Claim 6 (depends on 5) The image decoding device according to claim 5, wherein the circuit limits combinations of the selectable weighting coefficients according to a length of a motion vector of a small area or resolution of the motion vector. ### Claim 7 (depends on 5) The image decoding device according to claim 5, wherein the circuit limits combinations of the selectable weighting coefficients according to an angle relationship between the motion vector and a division boundary. ### Claim 8 (depends on 1) The image decoding device according to claim 1, wherein the circuit limits the selectable weighting coefficients according to an exposure time or a frame rate. ### Claim 9 (depends on 1) The image decoding device according to claim 1, wherein the circuit limits the selectable weighting coefficients according to a method of predicting a small area. ### Claim 10 (depends on 1) The image decoding device according to claim 1, wherein the circuit limits the selectable weighting coefficients according to a quantized parameter. ### Claim 11 (depends on 1) The image decoding device according to claim 1, wherein the circuit limits combinations of a selectable weighting coefficients of a decoding target block according to control information of a block near the decoding target block. ### Claim 12 (depends on 11) The image decoding device according to claim 11, wherein the circuit limits combinations of the selectable weighting coefficients of the decoding target block according to weighting coefficients of an adjacent decoded block. ### Claim 13 (depends on 12) The image decoding device according to claim 12, wherein the circuit adopts a width of a division boundary of a block having a continuous division boundary, as a combination of the decoding target block. ### Claim 14 (depends on 1) The image decoding device according to claim 1, wherein the circuit performs decoding by allocating a different code length according to a selection probability of the weighting coefficients. ### Claim 15 An image decoding method comprising: decoding control information and a quantized value; obtaining a decoded transform coefficient by performing inverse quantization on the decoded quantized value; obtaining a decoded prediction residual by performing inverse transform on the decoded transform coefficient; generating a first predicted sample based on a decoded sample and the decoded control information; accumulating the decoded sample; generating a second predicted sample based on the accumulated decoded sample and the decoded control information; generating a third predicted sample by weighted averaging using one of weighting coefficients limited based on the decoded control information for at least one of the first predicted sample or the second predicted sample; and obtaining the decoded sample by adding the decoded prediction residual and the third predicted sample. ### Claim 16 A program stored on a non-transitory computer-readable medium for causing a computer to function as an image decoding device including a circuit, wherein the circuit: decodes control information and a quantized value; obtains a decoded transform coefficient by performing inverse quantization on the decoded quantized value; obtains a decoded prediction residual by performing inverse transform on the decoded transform coefficient; generates a first predicted sample based on a decoded sample and the decoded control information; accumulates the decoded sample; generates a second predicted sample based on the accumulated decoded sample and the decoded control information; generates a third predicted sample by weighted averaging using one of weighting coefficients limited based on the decoded control information for at least one of the first predicted sample or the second predicted sample; and obtains the decoded sample by adding the decoded prediction residual and the third predicted sample.