/**
* gimp_color_profile_new_srgb:
*
* This function is a replacement for cmsCreate_sRGBProfile() and
* returns an sRGB profile that is functionally the same as the
* ArgyllCMS sRGB.icm profile. "Functionally the same" means it has
* the same red, green, and blue colorants and the V4 "chad"
* equivalent of the ArgyllCMS V2 white point. The profile TRC is also
* functionally equivalent to the ArgyllCMS sRGB.icm TRC and is the
* same as the LCMS sRGB built-in profile TRC.
*
* The actual primaries in the sRGB specification are
* red xy: {0.6400, 0.3300, 1.0}
* green xy: {0.3000, 0.6000, 1.0}
* blue xy: {0.1500, 0.0600, 1.0}
*
* The sRGB primaries given below are "pre-quantized" to compensate
* for hexadecimal quantization during the profile-making process.
* Unless the profile-making code compensates for this quantization,
* the resulting profile's red, green, and blue colorants will deviate
* slightly from the correct XYZ values.
*
* LCMS2 doesn't compensate for hexadecimal quantization. The
* "pre-quantized" primaries below were back-calculated from the
* ArgyllCMS sRGB.icm profile. The resulting sRGB profile's colorants
* exactly matches the ArgyllCMS sRGB.icm profile colorants.
*
* Return value: the sRGB #GimpColorProfile.
*
* Since: 2.10
**/
GimpColorProfile *
gimp_color_profile_new_srgb (void)
{
static GimpColorProfile *profile = NULL;
const guint8 *data;
gsize length;
if (G_UNLIKELY (profile == NULL))
{
cmsHPROFILE lcms_profile = gimp_color_profile_new_srgb_internal ();
profile = gimp_color_profile_new_from_lcms_profile (lcms_profile, NULL);
cmsCloseProfile (lcms_profile);
#if 0
/* for testing the code to get the colorants and make a new profile */
{
GimpMatrix3 matrix;
if (gimp_color_profile_get_rgb_matrix_colorants (profile, &matrix))
{
GimpColorProfile *test;
g_printerr ("Profile Red colorant XYZ: %1.8f, %1.8f, %1.8f \n",
matrix.coeff[0][0],
matrix.coeff[0][1],
matrix.coeff[0][2]);
g_printerr ("Profile Green colorant XYZ: %1.8f, %1.8f, %1.8f \n",
matrix.coeff[1][0],
matrix.coeff[1][1],
matrix.coeff[1][2]);
g_printerr ("Profile Blue colorant XYZ: %1.8f, %1.8f, %1.8f \n",
matrix.coeff[2][0],
matrix.coeff[2][1],
matrix.coeff[2][2]);
test = gimp_color_profile_new_foobar (profile);
g_object_unref (test);
}
}
#endif
}
data = gimp_color_profile_get_icc_profile (profile, &length);
return gimp_color_profile_new_from_icc_profile (data, length, NULL);
}
static GimpColorProfile *
gimp_color_profile_new_from_color_profile (GimpColorProfile *profile,
gboolean linear)
{
GimpColorProfile *new_profile;
cmsHPROFILE target_profile;
GimpMatrix3 matrix = { 0, };
cmsCIEXYZ *whitepoint;
cmsToneCurve *curve;
const gchar *model;
gchar *new_model;
g_return_val_if_fail (GIMP_IS_COLOR_PROFILE (profile), NULL);
if (gimp_color_profile_is_rgb (profile))
{
if (! gimp_color_profile_get_rgb_matrix_colorants (profile, &matrix))
return NULL;
}
else if (! gimp_color_profile_is_gray (profile))
{
return NULL;
}
whitepoint = cmsReadTag (profile->priv->lcms_profile,
cmsSigMediaWhitePointTag);
target_profile = cmsCreateProfilePlaceholder (0);
cmsSetProfileVersion (target_profile, 4.3);
cmsSetDeviceClass (target_profile, cmsSigDisplayClass);
cmsSetPCS (target_profile, cmsSigXYZData);
cmsWriteTag (target_profile, cmsSigMediaWhitePointTag, whitepoint);
if (linear)
{
/* linear light */
curve = cmsBuildGamma (NULL, 1.00);
gimp_color_profile_set_tag (target_profile, cmsSigProfileDescriptionTag,
"linear TRC variant generated by GIMP");
}
else
{
cmsFloat64Number srgb_parameters[5] =
{ 2.4, 1.0 / 1.055, 0.055 / 1.055, 1.0 / 12.92, 0.04045 };
/* sRGB curve */
curve = cmsBuildParametricToneCurve (NULL, 4, srgb_parameters);
gimp_color_profile_set_tag (target_profile, cmsSigProfileDescriptionTag,
"sRGB TRC variant generated by GIMP");
}
if (gimp_color_profile_is_rgb (profile))
{
cmsCIEXYZ red;
cmsCIEXYZ green;
cmsCIEXYZ blue;
cmsSetColorSpace (target_profile, cmsSigRgbData);
red.X = matrix.coeff[0][0];
red.Y = matrix.coeff[0][1];
red.Z = matrix.coeff[0][2];
green.X = matrix.coeff[1][0];
green.Y = matrix.coeff[1][1];
green.Z = matrix.coeff[1][2];
blue.X = matrix.coeff[2][0];
blue.Y = matrix.coeff[2][1];
blue.Z = matrix.coeff[2][2];
cmsWriteTag (target_profile, cmsSigRedColorantTag, &red);
cmsWriteTag (target_profile, cmsSigGreenColorantTag, &green);
cmsWriteTag (target_profile, cmsSigBlueColorantTag, &blue);
cmsWriteTag (target_profile, cmsSigRedTRCTag, curve);
cmsWriteTag (target_profile, cmsSigGreenTRCTag, curve);
cmsWriteTag (target_profile, cmsSigBlueTRCTag, curve);
}
else
{
cmsSetColorSpace (target_profile, cmsSigGrayData);
cmsWriteTag (target_profile, cmsSigGrayTRCTag, curve);
}
cmsFreeToneCurve (curve);
model = gimp_color_profile_get_model (profile);
if (model && g_str_has_prefix (model, "Generated from '"))
{
/* don't add multiple "Generated from 'foo'" */
new_model = g_strdup (model);
}
else
{
new_model = g_strdup_printf ("Generated from '%s'",
gimp_color_profile_get_description (profile));
}
gimp_color_profile_set_tag (target_profile, cmsSigDeviceMfgDescTag,
"GIMP");
gimp_color_profile_set_tag (target_profile, cmsSigDeviceModelDescTag,
new_model);
gimp_color_profile_set_tag (target_profile, cmsSigCopyrightTag,
"Public Domain");
g_free (new_model);
new_profile = gimp_color_profile_new_from_lcms_profile (target_profile, NULL);
cmsCloseProfile (target_profile);
return new_profile;
}
