In all the image analysis packages I've seen, the basic brightness and contrast adjustment functions use a simple straight-line relationship between the old and the new intensity - basically z = a + b.z0 where z0 is the old intensity and z is the new intensity value. 0 < b < 1 would give reduced contrast, b > 1 would increase contrast; to change brightness but not contrast keep b = 1 and change a. For RGB images you just process R, G and B identically. A fairly easy task IMHO!
- Re: Changing the brightness and contrast of an image displayed in ... Ben