Patent ID: 7081921
Filing Date: 2006-07-25
Classification: H04N

Abstract:
1. A front end signal processing method for processing a signal from an image sensor comprising the steps of: detecting luminance information included in a sensor output signal by receiving said image sensor output signal at a signal input of a correlated double sampler having a reference voltage terminal, detecting the luminance information included in said sensor output signal by means of said correlated double sampler, to generate an analog luminance signal representative of the detected luminance information; converting said analog luminance signal to a digital form to generate a digital luminance signal representative of the detected luminance information; clamping a black level of said luminance signal to a constant value based on said digital luminance signal by supplying a feedback signal produced from said digital luminance signal to said reference voltage terminal of said correlated double sampler; and digitally multiplying said digital luminance signal by a predetermined gain code to generate a front end processed signal output, wherein said step of digitally multiplying includes the steps of generating the predetermined gain code; digitally multiplying said digital luminance signal by said gain code to generate an amplified digital luminance signal; generating a pedestal code representative of a pedestal level; and adding said pedestal code to said amplified digital luminance signal to offset the multiplied digital luminance signal toward the positive side to generate the addition result as said front end processed signal output.