int cmsDetectBlackPoint(LPcmsCIEXYZ BlackPoint, cmsHPROFILE hProfile, int Intent, DWORD dwFlags)
{
// v4 + perceptual & saturation intents does have its own black point
if ((cmsGetProfileICCversion(hProfile) >= 0x4000000) &&
(Intent == INTENT_PERCEPTUAL || Intent == INTENT_SATURATION)) {
return GetV4PerceptualBlack(BlackPoint, hProfile, dwFlags);
}
#ifdef HONOR_BLACK_POINT_TAG
// v2, v4 rel/abs colorimetric
if (cmsIsTag(hProfile, icSigMediaBlackPointTag) &&
Intent == INTENT_RELATIVE_COLORIMETRIC) {
cmsCIEXYZ BlackXYZ, UntrustedBlackPoint, TrustedBlackPoint, MediaWhite;
cmsCIELab Lab;
// If black point is specified, then use it,
cmsTakeMediaBlackPoint(&BlackXYZ, hProfile);
cmsTakeMediaWhitePoint(&MediaWhite, hProfile);
// Black point is absolute XYZ, so adapt to D50 to get PCS value
cmsAdaptToIlluminant(&UntrustedBlackPoint, &MediaWhite, cmsD50_XYZ(), &BlackXYZ);
// Force a=b=0 to get rid of any chroma
cmsXYZ2Lab(NULL, &Lab, &UntrustedBlackPoint);
Lab.a = Lab.b = 0;
if (Lab.L > 50) Lab.L = 50; // Clip to L* <= 50
cmsLab2XYZ(NULL, &TrustedBlackPoint, &Lab);
// Return BP as D50 relative or absolute XYZ (depends on flags)
if (!(dwFlags & LCMS_BPFLAGS_D50_ADAPTED))
cmsAdaptToIlluminant(BlackPoint, cmsD50_XYZ(), &MediaWhite, &TrustedBlackPoint);
else
*BlackPoint = TrustedBlackPoint;
}
#endif
// If output profile, discount ink-limiting
if (Intent == INTENT_RELATIVE_COLORIMETRIC &&
(cmsGetDeviceClass(hProfile) == icSigOutputClass) &&
(cmsGetColorSpace(hProfile) == icSigCmykData))
return BlackPointUsingPerceptualBlack(BlackPoint, hProfile, dwFlags);
// Nope, compute BP using current intent.
return BlackPointAsDarkerColorant(hProfile, Intent, BlackPoint, dwFlags);
}
static
void ComputeBlackPointCompensationFactors(LPcmsCIEXYZ BlackPointIn,
LPcmsCIEXYZ WhitePointIn,
LPcmsCIEXYZ IlluminantIn,
LPcmsCIEXYZ BlackPointOut,
LPcmsCIEXYZ WhitePointOut,
LPcmsCIEXYZ IlluminantOut,
LPMAT3 m, LPVEC3 of)
{
cmsCIEXYZ RelativeBlackPointIn, RelativeBlackPointOut;
double ax, ay, az, bx, by, bz, tx, ty, tz;
// At first, convert both black points to relative.
cmsAdaptToIlluminant(&RelativeBlackPointIn, WhitePointIn, IlluminantIn, BlackPointIn);
cmsAdaptToIlluminant(&RelativeBlackPointOut, WhitePointOut, IlluminantOut, BlackPointOut);
// Now we need to compute a matrix plus an offset m and of such of
// [m]*bpin + off = bpout
// [m]*D50 + off = D50
//
// This is a linear scaling in the form ax+b, where
// a = (bpout - D50) / (bpin - D50)
// b = - D50* (bpout - bpin) / (bpin - D50)
tx = RelativeBlackPointIn.X - IlluminantIn ->X;
ty = RelativeBlackPointIn.Y - IlluminantIn ->Y;
tz = RelativeBlackPointIn.Z - IlluminantIn ->Z;
ax = (RelativeBlackPointOut.X - IlluminantOut ->X) / tx;
ay = (RelativeBlackPointOut.Y - IlluminantOut ->Y) / ty;
az = (RelativeBlackPointOut.Z - IlluminantOut ->Z) / tz;
bx = - IlluminantOut -> X * (RelativeBlackPointOut.X - RelativeBlackPointIn.X) / tx;
by = - IlluminantOut -> Y * (RelativeBlackPointOut.Y - RelativeBlackPointIn.Y) / ty;
bz = - IlluminantOut -> Z * (RelativeBlackPointOut.Z - RelativeBlackPointIn.Z) / tz;
MAT3identity(m);
m->v[VX].n[0] = ax;
m->v[VY].n[1] = ay;
m->v[VZ].n[2] = az;
VEC3init(of, bx, by, bz);
}
static
int BlackPointUsingPerceptualBlack(LPcmsCIEXYZ BlackPoint,
cmsHPROFILE hProfile,
DWORD dwFlags)
{
cmsHTRANSFORM hPercLab2CMYK, hRelColCMYK2Lab;
cmsHPROFILE hLab;
cmsCIELab LabIn, LabOut;
WORD CMYK[MAXCHANNELS];
cmsCIEXYZ BlackXYZ, MediaWhite;
if (!cmsIsIntentSupported(hProfile, INTENT_PERCEPTUAL, LCMS_USED_AS_INPUT)) {
BlackPoint -> X = BlackPoint ->Y = BlackPoint -> Z = 0.0;
return 0;
}
hLab = cmsCreateLabProfile(NULL);
hPercLab2CMYK = cmsCreateTransform(hLab, TYPE_Lab_DBL,
hProfile, TYPE_CMYK_16,
INTENT_PERCEPTUAL, cmsFLAGS_NOTPRECALC);
hRelColCMYK2Lab = cmsCreateTransform(hProfile, TYPE_CMYK_16,
hLab, TYPE_Lab_DBL,
INTENT_RELATIVE_COLORIMETRIC, cmsFLAGS_NOTPRECALC);
LabIn.L = LabIn.a = LabIn.b = 0;
cmsDoTransform(hPercLab2CMYK, &LabIn, CMYK, 1);
cmsDoTransform(hRelColCMYK2Lab, CMYK, &LabOut, 1);
if (LabOut.L > 50) LabOut.L = 50;
LabOut.a = LabOut.b = 0;
cmsDeleteTransform(hPercLab2CMYK);
cmsDeleteTransform(hRelColCMYK2Lab);
cmsCloseProfile(hLab);
cmsLab2XYZ(NULL, &BlackXYZ, &LabOut);
if (!(dwFlags & LCMS_BPFLAGS_D50_ADAPTED)){
cmsTakeMediaWhitePoint(&MediaWhite, hProfile);
cmsAdaptToIlluminant(BlackPoint, cmsD50_XYZ(), &MediaWhite, &BlackXYZ);
}
else
*BlackPoint = BlackXYZ;
return 1;
}
// Get Perceptual black of v4 profiles.
static
int GetV4PerceptualBlack(LPcmsCIEXYZ BlackPoint, cmsHPROFILE hProfile, DWORD dwFlags)
{
if (dwFlags & LCMS_BPFLAGS_D50_ADAPTED) {
BlackPoint->X = PERCEPTUAL_BLACK_X;
BlackPoint->Y = PERCEPTUAL_BLACK_Y;
BlackPoint->Z = PERCEPTUAL_BLACK_Z;
}
else {
cmsCIEXYZ D50BlackPoint, MediaWhite;
cmsTakeMediaWhitePoint(&MediaWhite, hProfile);
D50BlackPoint.X = PERCEPTUAL_BLACK_X;
D50BlackPoint.Y = PERCEPTUAL_BLACK_Y;
D50BlackPoint.Z = PERCEPTUAL_BLACK_Z;
cmsAdaptToIlluminant(BlackPoint, cmsD50_XYZ(), &MediaWhite, &D50BlackPoint);
}
return 1;
}
bool LcmsColorProfileContainer::init()
{
if (d->profile) {
cmsCloseProfile(d->profile);
}
d->profile = cmsOpenProfileFromMem((void *)d->data->rawData().constData(), d->data->rawData().size());
#ifndef NDEBUG
if (d->data->rawData().size() == 4096) {
qWarning() << "Profile has a size of 4096, which is suspicious and indicates a possible misuse of QIODevice::read(int), check your code.";
}
#endif
if (d->profile) {
wchar_t buffer[_BUFFER_SIZE_];
d->colorSpaceSignature = cmsGetColorSpace(d->profile);
d->deviceClass = cmsGetDeviceClass(d->profile);
cmsGetProfileInfo(d->profile, cmsInfoDescription, cmsNoLanguage, cmsNoCountry, buffer, _BUFFER_SIZE_);
d->name = QString::fromWCharArray(buffer);
//apparantly this should give us a localised string??? Not sure about this.
cmsGetProfileInfo(d->profile, cmsInfoModel, cmsNoLanguage, cmsNoCountry, buffer, _BUFFER_SIZE_);
d->productDescription = QString::fromWCharArray(buffer);
cmsGetProfileInfo(d->profile, cmsInfoManufacturer, cmsNoLanguage, cmsNoCountry, buffer, _BUFFER_SIZE_);
d->manufacturer = QString::fromWCharArray(buffer);
cmsGetProfileInfo(d->profile, cmsInfoCopyright, cmsNoLanguage, cmsNoCountry, buffer, _BUFFER_SIZE_);
d->copyright = QString::fromWCharArray(buffer);
cmsProfileClassSignature profile_class;
profile_class = cmsGetDeviceClass(d->profile);
d->valid = (profile_class != cmsSigNamedColorClass);
//This is where obtain the whitepoint, and convert it to the actual white point of the profile in the case a Chromatic adaption tag is
//present. This is necessary for profiles following the v4 spec.
cmsCIEXYZ baseMediaWhitePoint;//dummy to hold copy of mediawhitepoint if this is modified by chromatic adaption.
if (cmsIsTag(d->profile, cmsSigMediaWhitePointTag)) {
d->mediaWhitePoint = *((cmsCIEXYZ *)cmsReadTag(d->profile, cmsSigMediaWhitePointTag));
baseMediaWhitePoint = d->mediaWhitePoint;
cmsXYZ2xyY(&d->whitePoint, &d->mediaWhitePoint);
if (cmsIsTag(d->profile, cmsSigChromaticAdaptationTag)) {
//the chromatic adaption tag represent a matrix from the actual white point of the profile to D50.
cmsCIEXYZ *CAM1 = (cmsCIEXYZ *)cmsReadTag(d->profile, cmsSigChromaticAdaptationTag);
//We first put all our data into structures we can manipulate.
double d3dummy [3] = {d->mediaWhitePoint.X, d->mediaWhitePoint.Y, d->mediaWhitePoint.Z};
QGenericMatrix<1, 3, double> whitePointMatrix(d3dummy);
QTransform invertDummy(CAM1[0].X, CAM1[0].Y, CAM1[0].Z, CAM1[1].X, CAM1[1].Y, CAM1[1].Z, CAM1[2].X, CAM1[2].Y, CAM1[2].Z);
//we then abuse QTransform's invert function because it probably does matrix invertion 20 times better than I can program.
//if the matrix is uninvertable, invertedDummy will be an identity matrix, which for us means that it won't give any noticeble
//effect when we start multiplying.
QTransform invertedDummy = invertDummy.inverted();
//we then put the QTransform into a generic 3x3 matrix.
double d9dummy [9] = {invertedDummy.m11(), invertedDummy.m12(), invertedDummy.m13(),
invertedDummy.m21(), invertedDummy.m22(), invertedDummy.m23(),
invertedDummy.m31(), invertedDummy.m32(), invertedDummy.m33()
};
QGenericMatrix<3, 3, double> chromaticAdaptionMatrix(d9dummy);
//multiplying our inverted adaption matrix with the whitepoint gives us the right whitepoint.
QGenericMatrix<1, 3, double> result = chromaticAdaptionMatrix * whitePointMatrix;
//and then we pour the matrix into the whitepoint variable. Generic matrix does row/column for indices even though it
//uses column/row for initialising.
d->mediaWhitePoint.X = result(0, 0);
d->mediaWhitePoint.Y = result(1, 0);
d->mediaWhitePoint.Z = result(2, 0);
cmsXYZ2xyY(&d->whitePoint, &d->mediaWhitePoint);
}
}
//This is for RGB profiles, but it only works for matrix profiles. Need to design it to work with non-matrix profiles.
if (cmsIsTag(d->profile, cmsSigRedColorantTag)) {
cmsCIEXYZTRIPLE tempColorants;
tempColorants.Red = *((cmsCIEXYZ *)cmsReadTag(d->profile, cmsSigRedColorantTag));
tempColorants.Green = *((cmsCIEXYZ *)cmsReadTag(d->profile, cmsSigGreenColorantTag));
tempColorants.Blue = *((cmsCIEXYZ *)cmsReadTag(d->profile, cmsSigBlueColorantTag));
//convert to d65, this is useless.
cmsAdaptToIlluminant(&d->colorants.Red, &baseMediaWhitePoint, &d->mediaWhitePoint, &tempColorants.Red);
cmsAdaptToIlluminant(&d->colorants.Green, &baseMediaWhitePoint, &d->mediaWhitePoint, &tempColorants.Green);
cmsAdaptToIlluminant(&d->colorants.Blue, &baseMediaWhitePoint, &d->mediaWhitePoint, &tempColorants.Blue);
//d->colorants = tempColorants;
d->hasColorants = true;
} else {
//qDebug()<<d->name<<": has no colorants";
d->hasColorants = false;
}
//retrieve TRC.
if (cmsIsTag(d->profile, cmsSigRedTRCTag) && cmsIsTag(d->profile, cmsSigBlueTRCTag) && cmsIsTag(d->profile, cmsSigGreenTRCTag)) {
d->redTRC = ((cmsToneCurve *)cmsReadTag (d->profile, cmsSigRedTRCTag));
d->greenTRC = ((cmsToneCurve *)cmsReadTag (d->profile, cmsSigGreenTRCTag));
d->blueTRC = ((cmsToneCurve *)cmsReadTag (d->profile, cmsSigBlueTRCTag));
d->redTRCReverse = cmsReverseToneCurve(d->redTRC);
d->greenTRCReverse = cmsReverseToneCurve(d->greenTRC);
d->blueTRCReverse = cmsReverseToneCurve(d->blueTRC);
d->hasTRC = true;
} else if (cmsIsTag(d->profile, cmsSigGrayTRCTag)) {
d->grayTRC = ((cmsToneCurve *)cmsReadTag (d->profile, cmsSigGrayTRCTag));
d->grayTRCReverse = cmsReverseToneCurve(d->grayTRC);
d->hasTRC = true;
} else {
d->hasTRC = false;
}
// Check if the profile can convert (something->this)
d->suitableForOutput = cmsIsMatrixShaper(d->profile)
|| (cmsIsCLUT(d->profile, INTENT_PERCEPTUAL, LCMS_USED_AS_INPUT) &&
cmsIsCLUT(d->profile, INTENT_PERCEPTUAL, LCMS_USED_AS_OUTPUT));
d->version = cmsGetProfileVersion(d->profile);
d->defaultIntent = cmsGetHeaderRenderingIntent(d->profile);
d->isMatrixShaper = cmsIsMatrixShaper(d->profile);
d->isPerceptualCLUT = cmsIsCLUT(d->profile, INTENT_PERCEPTUAL, LCMS_USED_AS_INPUT);
d->isSaturationCLUT = cmsIsCLUT(d->profile, INTENT_SATURATION, LCMS_USED_AS_INPUT);
d->isAbsoluteCLUT = cmsIsCLUT(d->profile, INTENT_SATURATION, LCMS_USED_AS_INPUT);
d->isRelativeCLUT = cmsIsCLUT(d->profile, INTENT_RELATIVE_COLORIMETRIC, LCMS_USED_AS_INPUT);
return true;
}
return false;
}
static
int BlackPointAsDarkerColorant(cmsHPROFILE hInput,
int Intent,
LPcmsCIEXYZ BlackPoint,
DWORD dwFlags)
{
WORD *Black, *White;
cmsHTRANSFORM xform;
icColorSpaceSignature Space;
int nChannels;
DWORD dwFormat;
cmsHPROFILE hLab;
cmsCIELab Lab;
cmsCIEXYZ BlackXYZ, MediaWhite;
// If the profile does not support input direction, assume Black point 0
if (!cmsIsIntentSupported(hInput, Intent, LCMS_USED_AS_INPUT)) {
BlackPoint -> X = BlackPoint ->Y = BlackPoint -> Z = 0.0;
return 0;
}
// Try to get black by using black colorant
Space = cmsGetColorSpace(hInput);
if (!_cmsEndPointsBySpace(Space, &White, &Black, &nChannels)) {
BlackPoint -> X = BlackPoint ->Y = BlackPoint -> Z = 0.0;
return 0;
}
dwFormat = CHANNELS_SH(nChannels)|BYTES_SH(2);
hLab = cmsCreateLabProfile(NULL);
xform = cmsCreateTransform(hInput, dwFormat,
hLab, TYPE_Lab_DBL, Intent, cmsFLAGS_NOTPRECALC);
cmsDoTransform(xform, Black, &Lab, 1);
// Force it to be neutral, clip to max. L* of 50
Lab.a = Lab.b = 0;
if (Lab.L > 50) Lab.L = 50;
cmsCloseProfile(hLab);
cmsDeleteTransform(xform);
cmsLab2XYZ(NULL, &BlackXYZ, &Lab);
if (Intent == INTENT_ABSOLUTE_COLORIMETRIC) {
*BlackPoint = BlackXYZ;
}
else {
if (!(dwFlags & LCMS_BPFLAGS_D50_ADAPTED)) {
cmsTakeMediaWhitePoint(&MediaWhite, hInput);
cmsAdaptToIlluminant(BlackPoint, cmsD50_XYZ(), &MediaWhite, &BlackXYZ);
}
else
*BlackPoint = BlackXYZ;
}
return 1;
}
cmsBool CMSEXPORT cmsDetectBlackPoint(cmsCIEXYZ* BlackPoint, cmsHPROFILE hProfile, cmsUInt32Number Intent, cmsUInt32Number dwFlags)
{
// Zero for black point
if (cmsGetDeviceClass(hProfile) == cmsSigLinkClass) {
BlackPoint -> X = BlackPoint ->Y = BlackPoint -> Z = 0.0;
return FALSE;
}
// v4 + perceptual & saturation intents does have its own black point, and it is
// well specified enough to use it. Black point tag is deprecated in V4.
if ((cmsGetEncodedICCversion(hProfile) >= 0x4000000) &&
(Intent == INTENT_PERCEPTUAL || Intent == INTENT_SATURATION)) {
// Matrix shaper share MRC & perceptual intents
if (cmsIsMatrixShaper(hProfile))
return BlackPointAsDarkerColorant(hProfile, INTENT_RELATIVE_COLORIMETRIC, BlackPoint, 0);
// Get Perceptual black out of v4 profiles. That is fixed for perceptual & saturation intents
BlackPoint -> X = cmsPERCEPTUAL_BLACK_X;
BlackPoint -> Y = cmsPERCEPTUAL_BLACK_Y;
BlackPoint -> Z = cmsPERCEPTUAL_BLACK_Z;
return TRUE;
}
#ifdef CMS_USE_PROFILE_BLACK_POINT_TAG
// v2, v4 rel/abs colorimetric
if (cmsIsTag(hProfile, cmsSigMediaBlackPointTag) &&
Intent == INTENT_RELATIVE_COLORIMETRIC) {
cmsCIEXYZ *BlackPtr, BlackXYZ, UntrustedBlackPoint, TrustedBlackPoint, MediaWhite;
cmsCIELab Lab;
// If black point is specified, then use it,
BlackPtr = cmsReadTag(hProfile, cmsSigMediaBlackPointTag);
if (BlackPtr != NULL) {
BlackXYZ = *BlackPtr;
_cmsReadMediaWhitePoint(&MediaWhite, hProfile);
// Black point is absolute XYZ, so adapt to D50 to get PCS value
cmsAdaptToIlluminant(&UntrustedBlackPoint, &MediaWhite, cmsD50_XYZ(), &BlackXYZ);
// Force a=b=0 to get rid of any chroma
cmsXYZ2Lab(NULL, &Lab, &UntrustedBlackPoint);
Lab.a = Lab.b = 0;
if (Lab.L > 50) Lab.L = 50; // Clip to L* <= 50
cmsLab2XYZ(NULL, &TrustedBlackPoint, &Lab);
if (BlackPoint != NULL)
*BlackPoint = TrustedBlackPoint;
return TRUE;
}
}
#endif
// That is about v2 profiles.
// If output profile, discount ink-limiting and that's all
if (Intent == INTENT_RELATIVE_COLORIMETRIC &&
(cmsGetDeviceClass(hProfile) == cmsSigOutputClass) &&
(cmsGetColorSpace(hProfile) == cmsSigCmykData))
return BlackPointUsingPerceptualBlack(BlackPoint, hProfile);
// Nope, compute BP using current intent.
return BlackPointAsDarkerColorant(hProfile, Intent, BlackPoint, dwFlags);
}
