// Float xform converts floats. Since there are no performance issues, one routine does all job, including gamut check.
// Note that because extended range, we can use a -1.0 value for out of gamut in this case.
static
void FloatXFORM(_cmsTRANSFORM* p,
const void* in,
void* out, cmsUInt32Number Size, cmsUInt32Number Stride)
{
cmsUInt8Number* accum;
cmsUInt8Number* output;
cmsFloat32Number fIn[cmsMAXCHANNELS], fOut[cmsMAXCHANNELS];
cmsFloat32Number OutOfGamut;
cmsUInt32Number i, j;
accum = (cmsUInt8Number*) in;
output = (cmsUInt8Number*) out;
for (i=0; i < Size; i++) {
accum = p -> FromInputFloat(p, fIn, accum, Stride);
// Any gamut chack to do?
if (p ->GamutCheck != NULL) {
// Evaluate gamut marker.
cmsPipelineEvalFloat( fIn, &OutOfGamut, p ->GamutCheck);
// Is current color out of gamut?
if (OutOfGamut > 0.0) {
// Certainly, out of gamut
for (j=0; j < cmsMAXCHANNELS; j++)
fOut[j] = -1.0;
}
else {
// No, proceed normally
cmsPipelineEvalFloat(fIn, fOut, p -> Lut);
}
}
else {
// No gamut check at all
cmsPipelineEvalFloat(fIn, fOut, p -> Lut);
}
// Back to asked representation
output = p -> ToOutputFloat(p, fOut, output, Stride);
}
}
// The CLUT will be stored at 16 bits, but calculations are performed at cmsFloat32Number precision
static
int BlackPreservingSampler(register const cmsUInt16Number In[], register cmsUInt16Number Out[], register void* Cargo)
{
int i;
cmsFloat32Number Inf[4], Outf[4];
cmsFloat32Number LabK[4];
cmsFloat64Number SumCMY, SumCMYK, Error, Ratio;
cmsCIELab ColorimetricLab, BlackPreservingLab;
PreserveKPlaneParams* bp = (PreserveKPlaneParams*) Cargo;
// Convert from 16 bits to floating point
for (i=0; i < 4; i++)
Inf[i] = (cmsFloat32Number) (In[i] / 65535.0);
// Get the K across Tone curve
LabK[3] = cmsEvalToneCurveFloat(bp ->KTone, Inf[3]);
// If going across black only, keep black only
if (In[0] == 0 && In[1] == 0 && In[2] == 0) {
Out[0] = Out[1] = Out[2] = 0;
Out[3] = _cmsQuickSaturateWord(LabK[3] * 65535.0);
return TRUE;
}
// Try the original transform,
cmsPipelineEvalFloat( Inf, Outf, bp ->cmyk2cmyk);
// Store a copy of the floating point result into 16-bit
for (i=0; i < 4; i++)
Out[i] = _cmsQuickSaturateWord(Outf[i] * 65535.0);
// Maybe K is already ok (mostly on K=0)
if ( fabs(Outf[3] - LabK[3]) < (3.0 / 65535.0) ) {
return TRUE;
}
// K differ, mesure and keep Lab measurement for further usage
// this is done in relative colorimetric intent
cmsDoTransform(bp->hProofOutput, Out, &ColorimetricLab, 1);
// Is not black only and the transform doesn't keep black.
// Obtain the Lab of output CMYK. After that we have Lab + K
cmsDoTransform(bp ->cmyk2Lab, Outf, LabK, 1);
// Obtain the corresponding CMY using reverse interpolation
// (K is fixed in LabK[3])
if (!cmsPipelineEvalReverseFloat(LabK, Outf, Outf, bp ->LabK2cmyk)) {
// Cannot find a suitable value, so use colorimetric xform
// which is already stored in Out[]
return TRUE;
}
// Make sure to pass thru K (which now is fixed)
Outf[3] = LabK[3];
// Apply TAC if needed
SumCMY = Outf[0] + Outf[1] + Outf[2];
SumCMYK = SumCMY + Outf[3];
if (SumCMYK > bp ->MaxTAC) {
Ratio = 1 - ((SumCMYK - bp->MaxTAC) / SumCMY);
if (Ratio < 0)
Ratio = 0;
}
else
Ratio = 1.0;
Out[0] = _cmsQuickSaturateWord(Outf[0] * Ratio * 65535.0); // C
Out[1] = _cmsQuickSaturateWord(Outf[1] * Ratio * 65535.0); // M
Out[2] = _cmsQuickSaturateWord(Outf[2] * Ratio * 65535.0); // Y
Out[3] = _cmsQuickSaturateWord(Outf[3] * 65535.0);
// Estimate the error (this goes 16 bits to Lab DBL)
cmsDoTransform(bp->hProofOutput, Out, &BlackPreservingLab, 1);
Error = cmsDeltaE(&ColorimetricLab, &BlackPreservingLab);
if (Error > bp -> MaxError)
bp->MaxError = Error;
return TRUE;
}
// Float xform converts floats. Since there are no performance issues, one routine does all job, including gamut check.
// Note that because extended range, we can use a -1.0 value for out of gamut in this case.
static
void FloatXFORM(_cmsTRANSFORM* p,
const void* in,
void* out,
cmsUInt32Number PixelsPerLine,
cmsUInt32Number LineCount,
const cmsStride* Stride)
{
cmsUInt8Number* accum;
cmsUInt8Number* output;
cmsFloat32Number fIn[cmsMAXCHANNELS], fOut[cmsMAXCHANNELS];
cmsFloat32Number OutOfGamut;
cmsUInt32Number i, j, c, strideIn, strideOut;
_cmsHandleExtraChannels(p, in, out, PixelsPerLine, LineCount, Stride);
strideIn = 0;
strideOut = 0;
for (i = 0; i < LineCount; i++) {
accum = (cmsUInt8Number*)in + strideIn;
output = (cmsUInt8Number*)out + strideOut;
for (j = 0; j < PixelsPerLine; j++) {
accum = p->FromInputFloat(p, fIn, accum, Stride->BytesPerPlaneIn);
// Any gamut chack to do?
if (p->GamutCheck != NULL) {
// Evaluate gamut marker.
cmsPipelineEvalFloat(fIn, &OutOfGamut, p->GamutCheck);
// Is current color out of gamut?
if (OutOfGamut > 0.0) {
// Certainly, out of gamut
for (c = 0; c < cmsMAXCHANNELS; c++)
fOut[c] = -1.0;
}
else {
// No, proceed normally
cmsPipelineEvalFloat(fIn, fOut, p->Lut);
}
}
else {
// No gamut check at all
cmsPipelineEvalFloat(fIn, fOut, p->Lut);
}
output = p->ToOutputFloat(p, fOut, output, Stride->BytesPerPlaneOut);
}
strideIn += Stride->BytesPerLineIn;
strideOut += Stride->BytesPerLineOut;
}
}