#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