Patent ID: 9344605
Filing Date: 2016-05-17
CPC Classification: G06F,H04N

Claim Text:
1. A method for closed-loop color correction based on a multidimensional table, characterized in that the method comprises a step of performing by a processor loop color correction for color conversion based on a multidimensional table, wherein the color conversion establishes a mapping relationship between a set of input points and a set of output points using a multidimensional table, and the multidimensional table is represented by the following expressions wherein, In represents the input of the multidimensional table, each row of the matrix representing an input point and each column representing a color channel of an input point; n represents the number of color channels of an input point, indicating that the multidimensional table is a n dimensional look-up table; m represents the number of input points, indicating the number of nodes in the look-up table; Inpi Out represents the output of the multidimensional table, each row of the matrix representing an output point, and each column representing a color channel of an output point; the j-th row represents output values corresponding to input points represented by the j-th row of In; t represents the number of color channels of an output point; OutPi wherein performing loop color correction for color conversion based on the multidimensional table by the processor includes: Step 1: extracting sample points by the processor to form a color target pattern, the sample points on the color target pattern are used for data collection and calculation; Step 2: using color values by the processor in the color target pattern of step 1 as an input, retrieving device-independent output data from a target characteristic look-up table as target chromatic data, wherein the target chromatic data uses L*a*b* values specified by the International Commission on illumination; Step 3: printing the color target pattern produced in step 1 by a printer in communication with the processor, and then measuring color blocks in the color target pattern using a measurement instrument comprising an optical sensor to obtain measurement data, wherein the measurement data is L*a*b* value of each color block, the optical sensor being in communication with the processor; Step 4: calculating by the processor a degree of color difference between the measurement data and the target data, and correcting the target data according to the difference; Step 5: reproducing a color conversion table by the processor: Step 6: closed-loop correction by the processor, wherein steps 3 to 5 are repeated to perform closed-loop correction on the color conversion table, until satisfied or the occurrence of a rebound in average chromatic aberration.