1
// ==========================================================
2
// XYZ to RGB TIFF conversion routines
4
// Design and implementation by
5
// - Herv� Drolon (drolon@infonie.fr)
7
// This file is part of FreeImage 3
9
// COVERED CODE IS PROVIDED UNDER THIS LICENSE ON AN "AS IS" BASIS, WITHOUT WARRANTY
10
// OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, WITHOUT LIMITATION, WARRANTIES
11
// THAT THE COVERED CODE IS FREE OF DEFECTS, MERCHANTABLE, FIT FOR A PARTICULAR PURPOSE
12
// OR NON-INFRINGING. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE COVERED
13
// CODE IS WITH YOU. SHOULD ANY COVERED CODE PROVE DEFECTIVE IN ANY RESPECT, YOU (NOT
14
// THE INITIAL DEVELOPER OR ANY OTHER CONTRIBUTOR) ASSUME THE COST OF ANY NECESSARY
15
// SERVICING, REPAIR OR CORRECTION. THIS DISCLAIMER OF WARRANTY CONSTITUTES AN ESSENTIAL
16
// PART OF THIS LICENSE. NO USE OF ANY COVERED CODE IS AUTHORIZED HEREUNDER EXCEPT UNDER
19
// Use at your own risk!
20
// ==========================================================
22
#include "FreeImage.h"
23
#include "Utilities.h"
25
void tiff_ConvertLineXYZToRGB(BYTE *target, BYTE *source, double stonits, int width_in_pixels) {
26
FIRGBF *rgbf = (FIRGBF*)target;
27
float *xyz = (float*)source;
29
for (int cols = 0; cols < width_in_pixels; cols++) {
30
// assume CCIR-709 primaries (matrix from tif_luv.c)
31
// LOG Luv XYZ (D65) -> sRGB (CIE Illuminant E)
32
rgbf->red = (float)( 2.690*xyz[0] + -1.276*xyz[1] + -0.414*xyz[2]);
33
rgbf->green = (float)(-1.022*xyz[0] + 1.978*xyz[1] + 0.044*xyz[2]);
34
rgbf->blue = (float)( 0.061*xyz[0] + -0.224*xyz[1] + 1.163*xyz[2]);
38
rgbf->red = (float)(rgbf->red * stonits);
39
rgbf->green = (float)(rgbf->green * stonits);
40
rgbf->blue = (float)(rgbf->blue * stonits);
49
void tiff_ConvertLineRGBToXYZ(BYTE *target, BYTE *source, int width_in_pixels) {
50
FIRGBF *rgbf = (FIRGBF*)source;
51
float *xyz = (float*)target;
53
for (int cols = 0; cols < width_in_pixels; cols++) {
54
// assume CCIR-709 primaries, whitepoint x = 1/3 y = 1/3 (D_E)
55
// "The LogLuv Encoding for Full Gamut, High Dynamic Range Images" <G.Ward>
56
// sRGB ( CIE Illuminant E ) -> LOG Luv XYZ (D65)
57
xyz[0] = (float)(0.497*rgbf->red + 0.339*rgbf->green + 0.164*rgbf->blue);
58
xyz[1] = (float)(0.256*rgbf->red + 0.678*rgbf->green + 0.066*rgbf->blue);
59
xyz[2] = (float)(0.023*rgbf->red + 0.113*rgbf->green + 0.864*rgbf->blue);