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#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "gd.h"
#include "gd_color.h"
/**
* The threshold method works relatively well but it can be improved.
* Maybe L*a*b* and Delta-E will give better results (and a better
* granularity).
*/
int gdColorMatch(gdImagePtr im, int col1, int col2, float threshold)
{
const int dr = gdImageRed(im, col1) - gdImageRed(im, col2);
const int dg = gdImageGreen(im, col1) - gdImageGreen(im, col2);
const int db = gdImageBlue(im, col1) - gdImageBlue(im, col2);
const int da = gdImageAlpha(im, col1) - gdImageAlpha(im, col2);
const int dist = dr * dr + dg * dg + db * db + da * da;
return (100.0 * dist / 195075) < threshold;
}
/*
* To be implemented when we have more image formats.
* Buffer like gray8 gray16 or rgb8 will require some tweak
* and can be done in this function (called from the autocrop
* function. (Pierre)
*/
#if 0
static int colors_equal (const int col1, const in col2)
{
}
#endif
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