Patent ID: 7663678
Filing Date: 2010-02-16
Classification: G09G,H04N

Abstract:
1. A gamma correction method, comprising: inputting via a computer a value of a tone input signal Tin of X bits having non-linear tone-luminance characteristic; outputting via the computer a tone signal Tout of Y bits (X<Y) having the tone-luminance characteristic converted to a linear characteristic, producing an inverse gamma correction; and inputting via the computer said Tout and outputting the tone output signal of (N+M) bits formed of a set of Tn and Tm which is nearest to said Tout upon said Tout being expressed as A^Tn×Tm with a constant A, an index number indicated by the signal Tn of N bits and a mantissa indicated by the signal Tm of M bits, producing a format conversion; wherein A is a natural number power of 2, M satisfies the relationship M≦Y−N, the minimum value of N is 2 when A is 2 and 1 when A is larger than 2, and the maximum value of N which is determined on the basis of A and M is the maximum value resulting in that a set of the values of Tn and Tm becomes a set of different values for all values of Tin.