# US 12,192,523 B2 · Method and apparatus for image encoding/decoding > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,192,523 B2 - Document ID: US12192523B2 - Status: Granted - Kind: B2 - Application number: 18/365,601 - Filed: 2023-08-04 - Published: 2023-11-23 - Granted: 2025-01-07 - Earliest claimed: 2013-02-28 - Assignees: Research & Business Foundation Sungkyunkwan University - Applicants: Research & Business Foundation Sungkyunkwan University - Inventors: Byeung Woo Jeon; Kwang Hyun Won - Web page: https://patentgrep.com/patent/US12192523B2 ## CPC - H04N 19/61: in combination with predictive coding - H04N 19/12: Selection from among a plurality of transforms or standards, e.g. selection between discrete cosine transform [DCT] and sub-band transform or selection between H.263 and H.264 - H04N 19/14: Coding unit complexity, e.g. amount of activity or edge presence estimation (H04N19/146 takes precedence) - H04N 19/154: Measured or subjectively estimated visual quality after decoding, e.g. measurement of distortion (use of rate-distortion criteria H04N19/147) - 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 19/625: using discrete cosine transform [DCT] - H04N 19/91: Entropy coding, e.g. variable length coding [VLC] or arithmetic coding - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION ## Abstract Disclosed are a method and an apparatus for image encoding/decoding. The method for image decoding includes comparing whether a size of a current transform block and a size of a smallest transform block (smallest transform unit (STU)) are the same as each other, and decoding information indicating whether transformation is performed on the current transform block and determining whether to perform inverse transformation on the current transform block based on the decoded information indicating whether the transformation is performed when the size of the current transform block and the size of a smallest transform block are the same as each other. ## Claims ### Claim 1 A method of decoding an image, the method comprising: performing inter prediction for a current block using a motion vector and a reference picture to generate a prediction block for the current block; decoding information of a first block size to determine the first block size, wherein the first block size is determined by an encoder; decoding information indicating whether the skip of the transform process is applied, in response to the comparison of the first block size with the current block size; determining whether to perform an inverse transform on the current block based on the decoded information indicating whether the skip of the transform process is applied; performing or skipping the inverse transform on the current block to generate a residual block for the current block; and reconstructing the current block by adding the prediction block and the residual block. ### Claim 2 (depends on 1) The method of claim 1, wherein in response to the decoded information indicating that the transform process is not performed, the inverse transform on the current block is skipped. ### Claim 3 (depends on 1) The method of claim 1, wherein in response to the decoded information indicating that the transform process is performed, the inverse transform on the current block is performed. ### Claim 4 (depends on 1) The method of claim 1, wherein in response to a value of transform_skip_flag being 1, the transform process is not performed and is skipped on the current block, and in response to the value of transform_skip_flag being 0, the transform process is performed on the current block. ### Claim 5 (depends on 4) The method of claim 4, wherein the information indicating whether the skip of the transform process is applied comprises a flag indicating whether to perform the inverse transform on the current block based on the first block size. ### Claim 6 (depends on 1) The method of claim 1, further comprising performing an inverse transform on the current block according to the current block size, in response to the current block size satisfying a condition in which the skip of the transform process is not applied. ### Claim 7 (depends on 6) The method of claim 6, wherein the skip of the transform process is applied when the current block size is larger than 4×4 pixels. ### Claim 8 A method of encoding an image, the method comprising: performing inter prediction for a current block using a motion vector and a reference picture to generate a prediction block for the current block; generating a residual block for the current block by subtracting the prediction block from the current block; and encoding the residual block, wherein the encoding of the residual block comprises determining a first block size and encoding information of the first block size; determining whether to apply the skip of the transform process on the current block based on a comparison of the first block size with a current block size; and performing or skipping a transform on the current block to encode the residual block. ### Claim 9 (depends on 8) The method of claim 8, wherein in response to a value of transform_skip_flag being 1, the transform process is not performed and is skipped on the current block, and in response to the value of transform_skip_flag being 0, the transform process is performed on the current block. ### Claim 10 (depends on 8) The method of claim 8, further comprising encoding information indicating whether the skip of the transform process is applied to the current block. ### Claim 11 (depends on 10) The method of claim 10, wherein in response to a determination that the skip of the transform process is applied to the current block, the information indicating whether the skip of the transform process is applied to the current block indicates that the transform on the current block is skipped. ### Claim 12 (depends on 10) The method of claim 10, wherein in response to a determination that the skip of the transform process is not applied to the current block, the information indicating whether the skip of the transform process is applied to the current block indicates that the transform on the current block is performed. ### Claim 13 (depends on 11) The method of claim 11, further comprising performing the transform on the current block according to the current block size, in response to the current block size satisfying a condition in which the skip of the transform process is not applied. ### Claim 14 (depends on 10) The method of claim 10, wherein the information indicating whether the skip of the transform process is applied comprises a flag indicating whether to perform the transform on the current block based on the first block size. ### Claim 15 (depends on 14) The method of claim 14, wherein the skip of the transform process is applied when the current block size is larger than 4×4 pixels. ### Claim 16 A method of transmitting a bitstream which is generated by an image encoding method, the image encoding method comprising: performing inter prediction for a current block using a motion vector and a reference picture to generate a prediction block for the current block; generating a residual block for the current block by subtracting the prediction block from the current block; and encoding the residual block, wherein the encoding of the residual block comprises determining a first block size and encoding information of the first block size; determining whether to apply the skip of the transform process on the current block based on a comparison of the first block size with a current block size; and performing or skipping a transform on the current block to encode the residual block.