# US 2014/0153642 A1 · Image coding apparatus, image coding 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 2014/0153642 A1 - Document ID: US20140153642A1 - Status: Published application - Kind: A1 - Application number: 14/092,075 - Filed: 2013-11-27 - Published: 2014-06-05 - Earliest claimed: 2012-11-30 - Applicants: Canon Kabushiki Kaisha - Inventors: Hideaki Hattori - Web page: https://patentgrep.com/patent/US20140153642A1 ## CPC - H04N 19/159: Prediction type, e.g. intra-frame, inter-frame or bidirectional frame prediction - H04N 19/11: among a plurality of spatial predictive coding modes - H04N 19/176: the region being a block, e.g. a macroblock - H04N 19/186: the unit being a colour or a chrominance component - H04N 19/147: according to rate distortion criteria (rate-distortion as a criterion for motion estimation H04N19/567) - H04N 19/194: involving only two passes - H04N 19/59: involving spatial sub-sampling or interpolation, e.g. alteration of picture size or resolution - H04N 19/593: involving spatial prediction techniques - H04N 19/61: in combination with predictive coding - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION ## Abstract An image coding apparatus includes an acquisition unit configured to acquire a plurality of first values indicating an evaluation of each of a plurality of chrominance prediction modes which can be selected in coding of a chrominance component of a block to be coded and a plurality of second values indicating an evaluation of each of a plurality of luminance prediction modes which can be selected in coding of a luminance component of the block to be coded, and a determination unit configured to determine a luminance prediction mode to be used for the coding of the luminance component out of the plurality of luminance prediction modes, based on the plurality of first values and the plurality of second values acquired by the acquisition unit. ## Claims ### Claim 1 An image coding apparatus comprising: an acquisition unit configured to acquire a plurality of first values indicating an evaluation of each of a plurality of chrominance prediction modes which can be selected in coding of a chrominance component of a block to be coded and a plurality of second values indicating an evaluation of each of a plurality of luminance prediction modes which can be selected in coding of a luminance component of the block to be coded, and a determination unit configured to determine a luminance prediction mode to be used for the coding of the luminance component out of the plurality of luminance prediction modes based on the plurality of first values and the plurality of second values acquired by the acquisition unit. ### Claim 2 (depends on 1) The image coding apparatus according to claim 1, wherein each of the plurality of first values is associated with a coding amount calculated by coding of the chrominance component of the block to be coded using a respective one of the plurality of chrominance prediction modes. ### Claim 3 (depends on 1) The image coding apparatus according to claim 1, wherein each of the plurality of second values is associated with a coding amount calculated by coding of the luminance component of the block to be coded using a respective one of the plurality of luminance prediction modes. ### Claim 4 (depends on 1) The image coding apparatus according to claim 1, wherein the determination unit is configured to determine a luminance prediction mode to be used for the coding of the luminance component out of the plurality of luminance prediction modes based on a third value obtained by multiplying each of the plurality of first values acquired by the acquisition unit by a first weight, and a fourth value obtained by multiplying each of the plurality of second values acquired by the acquisition unit by a second weight. ### Claim 5 (depends on 4) The image coding apparatus according to claim 4, wherein the first weight is determined based on a quantization parameter in the coding of the chrominance component of the block to be coded, and the second weight is determined based on a quantization parameter in the coding of the luminance component of the block to be coded. ### Claim 6 (depends on 4) The image coding apparatus according to claim 4, wherein the first weight is determined based on a sample number of the chrominance component of the block to be coded; and the second weight is determined based on a sample number of the luminance component of the block to be coded. ### Claim 7 (depends on 1) The image coding apparatus according to claim 1, wherein the determination unit is configured to determine the chrominance prediction mode to be used for the coding of the chrominance component of the block to be coded out of the plurality of chrominance prediction modes based on the luminance prediction mode determined by the determination unit and the first value acquired by the acquisition unit. ### Claim 8 (depends on 1) The image coding apparatus according to claim 1, wherein the acquisition unit is configured to acquire a first value indicating an evaluation value of a predetermined mode out of the plurality of chrominance prediction modes and a plurality of second values indicating the evaluation of each of the plurality of luminance prediction modes, and the determination unit is configured to, if a value equal to a predetermined value or less than the predetermined value exists among the first values, determine the luminance prediction mode to be used for the coding of the luminance component out of the plurality of luminance prediction modes based on the plurality of second values acquired by the acquisition unit. ### Claim 9 (depends on 8) The image coding apparatus according to claim 8, wherein the predetermined mode is a mode which can be used for the coding of the chrominance component of the block to be coded even if the luminance prediction mode to be used for the coding of the luminance component of the block to be coded is any of the plurality of luminance prediction modes. ### Claim 10 (depends on 8) The image coding apparatus according to claim 8, wherein the predetermined mode is at least one of a horizontal mode, a vertical mode, a DC mode, and a planar mode. ### Claim 11 An image coding method comprising: acquiring a plurality of first values indicating an evaluation of each of a plurality of prediction modes which can be selected in coding of a chrominance component of a block to be coded and a plurality of second values indicating an evaluation of each of a plurality of modes which can be selected in coding of a luminance component of the block to be coded, and determining a luminance prediction mode to be used for the coding of the luminance component out of the plurality of luminance prediction modes, based on the acquired plurality of first values and the plurality of second values. ### Claim 12 (depends on 11) The image coding method according to claim 11, wherein determining the luminance prediction mode is determining the luminance prediction mode to be used for the coding of the luminance component out of the plurality of luminance prediction modes based on a third value obtained by multiplying each of the acquired plurality of first values by a first weight and a fourth value obtained by multiplying each of the acquired plurality of second values acquired by a second weight. ### Claim 13 A non-transitory computer-readable storage medium storing a program for causing a computer to execute image coding, the program comprising: computer-executable instructions to acquire a plurality of first values indicating an evaluation of each of a plurality of chrominance prediction modes which can be selected in coding of a chrominance component of a block to be coded and a plurality of second values indicating an evaluation of each of a plurality of luminance prediction modes which can be selected in coding of a luminance component of the block to be coded, and computer-executable instructions to determine a luminance prediction mode to be used for the coding of the luminance component out of the plurality of luminance prediction modes, based on the plurality of first values and the plurality of second values acquired by the acquisition unit.