# US 12,225,179 B2 · Image data encoding/decoding method and apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,225,179 B2 - Document ID: US12225179B2 - Status: Granted - Kind: B2 - Application number: 18/503,877 - Filed: 2023-11-07 - Published: 2024-02-29 - Granted: 2025-02-11 - Earliest claimed: 2016-10-04 - Assignees: B1 Institute of Image Technology, Inc. - Applicants: B1 Institute of Image Technology, Inc. - Inventors: Ki Baek Kim - Web page: https://patentgrep.com/patent/US12225179B2 ## CPC - H04N 13/161: Encoding, multiplexing or demultiplexing different image signal components (for multi-view video sequence encoding H04N19/597) - G06T 3/40: Scaling of whole images or parts thereof, e.g. expanding or contracting - H04N 19/103: Selection of coding mode or of prediction mode - 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 19/11: among a plurality of spatial predictive coding modes - H04N 19/119: Adaptive subdivision aspects, e.g. subdivision of a picture into rectangular or non-rectangular coding blocks - H04N 19/124: Quantisation - H04N 19/129: Scanning of coding units, e.g. zig-zag scan of transform coefficients or flexible macroblock ordering [FMO] - H04N 19/13: Adaptive entropy coding, e.g. adaptive variable length coding [AVLC] or context adaptive binary arithmetic coding [CABAC] - H04N 19/134: characterised by the element, parameter or criterion affecting or controlling the adaptive coding - 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 19/159: Prediction type, e.g. intra-frame, inter-frame or bidirectional frame prediction - H04N 19/167: Position within a video image, e.g. region of interest [ROI] - H04N 19/172: the region being a picture, frame or field - H04N 19/174: the region being a slice, e.g. a line of blocks or a group of blocks - H04N 19/176: the region being a block, e.g. a macroblock - H04N 19/55: Motion estimation with spatial constraints, e.g. at image or region borders - H04N 19/597: specially adapted for multi-view video sequence encoding - H04N 19/625: using discrete cosine transform [DCT] - H04N 19/70: characterised by syntax aspects related to video coding, e.g. related to compression standards - H04N 23/698: for achieving an enlarged field of view, e.g. panoramic image capture - H04N 19/61: in combination with predictive coding - H04N 19/96: Tree coding, e.g. quad-tree coding - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION - G06T: IMAGE DATA PROCESSING OR GENERATION, IN GENERAL ## Abstract Disclosed are methods and apparatuses for decoding an image. A method includes receiving a bitstream obtained by encoding the image; dividing a first coding block into a plurality of second coding blocks; generating a prediction block of a second coding block based on syntax information obtained from the bitstream; and reconstructing the second coding block based on the prediction block and a residual block of the second coding block, the residual block being obtained by performing a dequantization and an inverse-transform on quantized transform coefficients from the bitstream. The first coding block has a recursive division structure. The first coding block is divided based on at least one of a quad tree division, a binary tree division or a triple tree division. ## Claims ### Claim 1 A method of decoding an image with a decoding apparatus, comprising: receiving a bitstream in which the image is encoded; obtaining, from the bitstream, a single index for specifying a block division type of a current block in the image; determining, based on the single index, the block division type of the current block from a candidate group pre-defined in the decoding apparatus, wherein the single index is used to select one candidate division types among a plurality of candidate division types included in the candidate group, wherein the plurality of candidate division types include a non-division, a first quad-division, a second quad-division, a binary-division and a triple-division, and wherein the first quad-division is representative of dividing, based on one horizontal line and one vertical line, one coding block into four coding blocks, the second quad-division is representative of dividing, based on three horizontal lines or three vertical lines, one coding block into four coding blocks, the binary-division is representative of dividing one coding block into two coding blocks, and the triple-division is representative of dividing one coding block into three coding blocks, wherein the binary-division includes a horizontal binary-division and a vertical binary-division, and wherein the bitstream includes a first flag specifying whether to perform the horizontal binary-division and a second flag specifying whether to perform the vertical binary-division, the first flag being different from the second flag; dividing, based on the determined block division type, the current block into a plurality of sub-blocks; and decoding each of the sub-blocks with reference to syntax information obtained from the bitstream; and reconstructing the current block based on the decoded sub-blocks, wherein the four coding blocks obtained by the second quad-division have the same size each other, and wherein the sub-block is decoded by performing a prediction method selected from among a plurality of prediction methods. ### Claim 2 (depends on 1) The method of claim 1, wherein the current block is set equal to a largest coding block or is set a block resulting from dividing the largest coding block, wherein a size of the largest coding block is variably determined based on information on the largest coding block, wherein the information on the largest coding block is signaled from the bitstream. ### Claim 3 (depends on 2) The method of claim 2, wherein the size of the largest coding block is set equal to 128×128 or 64×64 according to the information on the largest coding block. ### Claim 4 (depends on 1) The method of claim 1, wherein a number of the candidate division types available for the current block is different dependent on at least one of a size of the current block or a shape of the current block. ### Claim 5 (depends on 4) The method of claim 4, wherein when the size of the current block is equal to or greater than 16×16, the candidate group for the current block includes the non-division, the first quad-division, the second quad-division, the binary-division, and the triple-division, and when the size of the current block is less than 16×16, the candidate group for the current block does not include at least one of the second quad-division or the triple-division. ### Claim 6 A method of encoding an image with an encoding apparatus, comprising: determining a block division type of a current block in the image from a candidate group pre-defined in the encoding apparatus; encoding single index for specifying the determined block division type of the current block; and encoding each of sub-blocks resulting from dividing the current block based on the determined block division type, wherein the encoded sub-blocks are decoded to reconstruct the current block, wherein the single index is used to select one candidate division types among a plurality of candidate division types included in the candidate group, wherein the plurality of candidate division types include a non-division, a first quad-division, a second quad-division, a binary-division and a triple-division, and wherein the first quad-division is representative of dividing, based on one horizontal line and one vertical line, one coding block into four coding blocks, the second quad-division is representative of dividing, based on three horizontal lines or three vertical lines, one coding block into four coding blocks, the binary-division is representative of dividing one coding block into two coding blocks, and the triple-division is representative of dividing one coding block into three coding blocks, wherein the binary-division includes a horizontal binary-division and a vertical binary-division, wherein the bitstream includes a first flag specifying whether to perform the horizontal binary-division and a second flag specifying whether to perform the vertical binary-division, the first flag being different from the second flag, wherein the four coding blocks obtained by the second quad-division have the same size each other, and wherein the sub-block is encoded by performing a prediction method selected from among a plurality of prediction methods. ### Claim 7 A non-transitory computer-readable recording medium storing a bitstream that is generated by a method of encoding an image with an encoding apparatus, the method comprising: determining a block division type of a current block in the image from a candidate group pre-defined in the encoding apparatus; encoding single index for specifying the determined block division type of the current block; and encoding each of sub-blocks resulting from dividing the current block based on the determined block division type, wherein the encoded sub-blocks are decoded to reconstruct the current block, wherein the single index is used to select one candidate division types among a plurality of candidate division types included in the candidate group, wherein the plurality of candidate division types include a non-division, a first quad-division, a second quad-division, a binary-division and a triple-division, wherein the first quad-division is representative of dividing, based on one horizontal line and one vertical line, one coding block into four coding blocks, the second quad-division is representative of dividing, based on three horizontal lines or three vertical lines, one coding block into four coding blocks, the binary-division is representative of dividing one coding block into two coding blocks, and the triple-division is representative of dividing one coding block into three coding blocks, wherein the binary-division includes a horizontal binary-division and a vertical binary-division, wherein the bitstream includes a first flag specifying whether to perform the horizontal binary-division and a second flag specifying whether to perform the vertical binary-division, the first flag being different from the second flag, wherein the four coding blocks obtained by the second quad-division have the same size each other, and wherein the sub-block is encoded by performing a prediction method selected from among a plurality of prediction methods. ### Claim 8 A method for transmitting a bitstream, the method comprising: obtaining the bitstream that is generated by a method of encoding an image with an encoding apparatus; and transmitting the bitstream, wherein the method of encoding the image comprises determining a block division type of a current block in the image from a candidate group pre-defined in the encoding apparatus; encoding single index for specifying the determined block division type of the current block; and encoding each of sub-blocks resulting from dividing the current block based on the determined block division type, wherein the encoded sub-blocks are decoded to reconstruct the current block, wherein the single index is used to select one candidate division types among a plurality of candidate division types included in the candidate group, wherein the plurality of candidate division types include a non-division, a first quad-division, a second quad-division, a binary-division and a triple-division, wherein the first quad-division is representative of dividing, based on one horizontal line and one vertical line, one coding block into four coding blocks, the second quad-division is representative of dividing, based on three horizontal lines or three vertical lines, one coding block into four coding blocks, the binary-division is representative of dividing one coding block into two coding blocks, and the triple-division is representative of dividing one coding block into three coding blocks, wherein the binary-division includes a horizontal binary-division and a vertical binary-division, wherein the bitstream includes a first flag specifying whether to perform the horizontal binary-division and a second flag specifying whether to perform the vertical binary-division, the first flag being different from the second flag, wherein the four coding blocks obtained by the second quad-division have the same size each other, and wherein the sub-block is encoded by performing a prediction method selected from among a plurality of prediction methods.