GAMMA CORRECTION CIRCUIT AND KNEE CORRECTION CIRCUIT

摘要

PROBLEM TO BE SOLVED: To obtain a smooth characteristic at junction of broken lines when approximating gamma correction and knee correction by using a plurality of broken lines. SOLUTION: A 1st gamma-processing circuit 5 or a 1st knee processing circuit and a 2nd gamma-processing circuit or a 2nd knee-processing circuit process in parallel a signal obtained, by adding an input offset value (k) to a digitized video input signal (x) and a signal obtained by subtracting the value (k) from the signal (x), and the mean value of the two signals is defined as a video output signal (y). Thus, a correction processing is performed by a broken line which uses the mean value of inclinations of adjacent broken lines as its inclination at the junction of the broken lines, and adverse effects due to discontinuity of inclination at the junction of the broken lines on an image can be prevented.