Patent ID: 8054374

Claim:
An image brightness correction method, for correcting a brightness gain of a shot image to a uniform level after a camera device shoots the image with a flash lamp turned on, the method comprising: the camera device firing a pre-flash and shooting an image according to the pre-flash; capturing an automatic exposure time of the camera device, and estimating a main flash duration according to the image and the automatic exposure time of the camera device; firing a main flash according to the main flash duration, and shooting a raw image; calculating a brightness gain value of the raw image, and calculating an inadequate brightness gain ratio of the raw image according to a preset gain threshold value; and according to the inadequate brightness gain ratio of the raw image, recalculating a color gain value of the raw image, and outputting the compensated color gain value as a preset image file wherein the inadequate brightness gain ratio of the raw image is denoted by a following mathematical expression: the inadequate brightness gain ratio of the raw image=the preset gain threshold value/the brightness gain value of the raw image.