Patent ID: 7542601

Claim:
A method for enhancing an image quality by changing a saturation value through converting analog signals outputted from an pixel array of an image sensor into digital signals and then multiplying a saturation value set by a user with signal values ‘Cr’ and ‘Cb’ except for a brightness component ‘Y’ among the digital signals, wherein the analog signals which are weak are divided into a first to a third ranges based on a minimum gain value ‘SatGainMin’ and a maximum gain value ‘SatGainMax’ of a gain value ‘PGain’ of a pre-amplifier for amplifying the analog signals through changing a gain per brightness level, the method is carried out by a saturation suppression block to perform the following steps: using N which is a positive integer as an actual saturation value ‘ASat’ in the first range where the ‘PGain’ is less than the ‘SatGainMin’; using M which is a positive integer equal to or less than the N as the ‘ASat’ in the third range where the ‘PGain’ is greater than the ‘SatGainMax’; and using a value of a linear function with a slope decreasing linearly from the N to the M as the ‘ASat’ in the second range where the ‘PGain’ is equal to or greater than the ‘SatGainMin’ and equal to or less than the ‘SatGainMax’.