Patent ID: 7801355

Claim:
A method of processing an image performed by an image processing device, the image being output from a single-chip color image capturing sensor having a first color pixel, a second color pixel, and a third color pixel, the method comprising: calculating, with a processor of the image processing device, first color data including a first color value, a second color value, and a third color value by an interpolation process, the first color data being color data of the first color pixel; converting, with the processor, the first color data to a first brightness signal Y and a first color-difference signal C, the first brightness signal Y being calculated by a first transformation formula selected from a plurality of transformation formulas based on a threshold value condition determined by a difference between the first color value and a value proportionate to the second color value and by a difference between the third color value and the value proportionate to the second color value, and the first color-difference signal C calculated by a difference between the first color value and the first brightness signal Y, the converting of the first color data including converting the first color data into a second brightness signal Y and a second color-difference signal C, the second brightness signal Y being calculated by a second transformation formula selected from the plurality of transformation formulas based on the threshold value condition, and the second color-difference signal C calculated by a difference between the first color value and the second brightness signal Y; synthesizing, with the processor, the first brightness signal Y and the second brightness signal Y to generate a third brightness signal Y and synthesizing the first color-difference signal C and the second color-difference signal C to generate a third color-difference signal C; and performing, with the processor, a filtering process on the third brightness signal Y to enhance a high spatial frequency component and on the third color-difference signal C to enhance a low spatial frequency component.