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src/Source/FreeImageToolkit/Colors.cpp  view on Meta::CPAN

 // snippet 2: brightness, contrast
 FreeImage_AdjustBrightness(dib, 50.0);
 FreeImage_AdjustContrast(dib, 15.0);
 
 Better and even faster would be snippet 3:
 
 // snippet 3:
 FreeImage_AdjustColors(dib, 50.0, 15.0, 1.0, FALSE);
 
 @param dib Input/output image to be processed.
 @param brightness Percentage brightness value where -100 <= brightness <= 100<br>
 A value of 0 means no change, less than 0 will make the image darker and greater
 than 0 will make the image brighter.
 @param contrast Percentage contrast value where -100 <= contrast <= 100<br>
 A value of 0 means no change, less than 0 will decrease the contrast
 and greater than 0 will increase the contrast of the image.
 @param gamma Gamma value to be used for gamma correction. A value of 1.0 leaves
 the image alone, less than one darkens it, and greater than one lightens it.<br>
 This parameter must not be zero or smaller than zero. If so, it will be ignored
 and no gamma correction will be performed on the image.
 @param invert If set to TRUE, the image will be inverted.
 @return Returns TRUE on success, FALSE otherwise (e.g. when the bitdeph of the
 source dib cannot be handled).
 */
BOOL DLL_CALLCONV
FreeImage_AdjustColors(FIBITMAP *dib, double brightness, double contrast, double gamma, BOOL invert) {
	BYTE LUT[256];

	if (!FreeImage_HasPixels(dib) || (FreeImage_GetImageType(dib) != FIT_BITMAP)) {
		return FALSE;
	}

	int bpp = FreeImage_GetBPP(dib);
	if ((bpp != 8) && (bpp != 24) && (bpp != 32)) {
		return FALSE;
	}

	if (FreeImage_GetAdjustColorsLookupTable(LUT, brightness, contrast, gamma, invert)) {
		return FreeImage_AdjustCurve(dib, LUT, FICC_RGB);
	}
	return FALSE;
}

/** @brief Applies color mapping for one or several colors on a 1-, 4- or 8-bit
 palletized or a 16-, 24- or 32-bit high color image.

 This function maps up to <i>count</i> colors specified in <i>srccolors</i> to
 these specified in <i>dstcolors</i>. Thereby, color <i>srccolors[N]</i>,
 if found in the image, will be replaced by color <i>dstcolors[N]</i>. If
 parameter <i>swap</i> is TRUE, additionally all colors specified in
 <i>dstcolors</i> are also mapped to these specified in <i>srccolors</i>. For
 high color images, the actual image data will be modified whereas, for
 palletized images only the palette will be changed.<br>

 The function returns the number of pixels changed or zero, if no pixels were
 changed. 

 Both arrays <i>srccolors</i> and <i>dstcolors</i> are assumed not to hold less
 than <i>count</i> colors.<br>

 For 16-bit images, all colors specified are transparently converted to their 
 proper 16-bit representation (either in RGB555 or RGB565 format, which is
 determined by the image's red- green- and blue-mask).<br>

 <b>Note, that this behaviour is different from what FreeImage_ApplyPaletteIndexMapping()
 does, which modifies the actual image data on palletized images.</b>

 @param dib Input/output image to be processed.
 @param srccolors Array of colors to be used as the mapping source.
 @param dstcolors Array of colors to be used as the mapping destination.
 @param count The number of colors to be mapped. This is the size of both
 <i>srccolors</i> and <i>dstcolors</i>.  
 @param ignore_alpha If TRUE, 32-bit images and colors are treated as 24-bit.
 @param swap If TRUE, source and destination colors are swapped, that is,
 each destination color is also mapped to the corresponding source color.  
 @return Returns the total number of pixels changed. 
 */
unsigned DLL_CALLCONV
FreeImage_ApplyColorMapping(FIBITMAP *dib, RGBQUAD *srccolors, RGBQUAD *dstcolors, unsigned count, BOOL ignore_alpha, BOOL swap) {
	unsigned result = 0;

	if (!FreeImage_HasPixels(dib) || (FreeImage_GetImageType(dib) != FIT_BITMAP)) {
		return 0;
	}

	// validate parameters
	if ((!srccolors) || (!dstcolors)|| (count < 1)) {
		return 0;
	}

	int bpp = FreeImage_GetBPP(dib);
	switch (bpp) {
		case 1:
		case 4:
		case 8: {
			unsigned size = FreeImage_GetColorsUsed(dib);
			RGBQUAD *pal = FreeImage_GetPalette(dib);
			RGBQUAD *a, *b;
			for (unsigned x = 0; x < size; x++) {
				for (unsigned j = 0; j < count; j++) {
					a = srccolors;
					b = dstcolors;
					for (int i = (swap ? 0 : 1); i < 2; i++) {
						if ((pal[x].rgbBlue == a[j].rgbBlue)&&(pal[x].rgbGreen == a[j].rgbGreen) &&(pal[x].rgbRed== a[j].rgbRed)) {
							pal[x].rgbBlue = b[j].rgbBlue;
							pal[x].rgbGreen = b[j].rgbGreen;
							pal[x].rgbRed = b[j].rgbRed;
							result++;
							j = count;
							break;
						}
						a = dstcolors;
						b = srccolors;
					}
				}
			}
			return result;
		}
		case 16: {
			WORD *src16 = (WORD *)malloc(sizeof(WORD) * count);
			if (NULL == src16) {