c# - How to 'normalize' a grayscale image? -


my math bit rusty. i'm trying equalize histogram of 2d array represents grayscale values in range 0-255 (values may not whole numbers because of how computed).

i found this article on wikipedia, don't quite understand formulas present.

ni, n , l can compute, i'm not quite sure how implement cdf function. might this function of use?

here's i've got far:

static double[,] normalize(double[,] mat) {     int width = mat.getlength(0);     int height = mat.getlength(1);     int npixels = width*height;      double sum = 0;     double max = double.minvalue;     double min = double.maxvalue;     var graylevels = new dictionary<double, int>();      foreach (var g in mat)     {         sum += g;         if (g > max) max = g;         if (g < min) min = g;         if (!graylevels.containskey(g)) graylevels[g] = 0;         ++graylevels[g];     }     double avg = sum/npixels;     double range = max - min;      var = new double[width,height];      // how normalize?      return i; }

found might find useful

http://sonabstudios.blogspot.in/2011/01/histogram-equalization-algorithm.html

hope helps


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