www.gusucode.com > 一个虹膜识别的Matlab程序源码 > Segmentation/adjgamma.m
% ADJGAMMA - Adjusts image gamma. % % function g = adjgamma(im, g) % % Arguments: % im - image to be processed. % g - image gamma value. % Values in the range 0-1 enhance contrast of bright % regions, values > 1 enhance contrast in dark % regions. % Author: Peter Kovesi % Department of Computer Science & Software Engineering % The University of Western Australia % pk@cs.uwa.edu.au www.cs.uwa.edu.au/~pk % July 2001 function newim = adjgamma(im, g) if g <= 0 error('Gamma value must be > 0'); end if isa(im,'uint8'); newim = double(im); else newim = im; end % rescale range 0-1 newim = newim-min(min(newim)); newim = newim./max(max(newim)); newim = newim.^(1/g); % Apply gamma function