1 //---------------------------------------------------------------------------------
3 // Little Color Management System
4 // Copyright (c) 1998-2011 Marti Maria Saguer
6 // Permission is hereby granted, free of charge, to any person obtaining
7 // a copy of this software and associated documentation files (the "Software"),
8 // to deal in the Software without restriction, including without limitation
9 // the rights to use, copy, modify, merge, publish, distribute, sublicense,
10 // and/or sell copies of the Software, and to permit persons to whom the Software
11 // is furnished to do so, subject to the following conditions:
13 // The above copyright notice and this permission notice shall be included in
14 // all copies or substantial portions of the Software.
16 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
17 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO
18 // THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
19 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
20 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
21 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
22 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
24 //---------------------------------------------------------------------------------
27 #include "lcms2_internal.h"
30 // Allocates an empty multi profile element
31 cmsStage* CMSEXPORT _cmsStageAllocPlaceholder(cmsContext ContextID,
32 cmsStageSignature Type,
33 cmsUInt32Number InputChannels,
34 cmsUInt32Number OutputChannels,
35 _cmsStageEvalFn EvalPtr,
36 _cmsStageDupElemFn DupElemPtr,
37 _cmsStageFreeElemFn FreePtr,
40 cmsStage* ph = (cmsStage*) _cmsMallocZero(ContextID, sizeof(cmsStage));
42 if (ph == NULL) return NULL;
45 ph ->ContextID = ContextID;
48 ph ->Implements = Type; // By default, no clue on what is implementing
50 ph ->InputChannels = InputChannels;
51 ph ->OutputChannels = OutputChannels;
52 ph ->EvalPtr = EvalPtr;
53 ph ->DupElemPtr = DupElemPtr;
54 ph ->FreePtr = FreePtr;
62 void EvaluateIdentity(const cmsFloat32Number In[],
63 cmsFloat32Number Out[],
66 memmove(Out, In, mpe ->InputChannels * sizeof(cmsFloat32Number));
70 cmsStage* CMSEXPORT cmsStageAllocIdentity(cmsContext ContextID, cmsUInt32Number nChannels)
72 return _cmsStageAllocPlaceholder(ContextID,
73 cmsSigIdentityElemType,
81 // Conversion functions. From floating point to 16 bits
83 void FromFloatTo16(const cmsFloat32Number In[], cmsUInt16Number Out[], cmsUInt32Number n)
87 for (i=0; i < n; i++) {
88 Out[i] = _cmsQuickSaturateWord(In[i] * 65535.0);
92 // From 16 bits to floating point
94 void From16ToFloat(const cmsUInt16Number In[], cmsFloat32Number Out[], cmsUInt32Number n)
98 for (i=0; i < n; i++) {
99 Out[i] = (cmsFloat32Number) In[i] / 65535.0F;
104 // This function is quite useful to analyze the structure of a LUT and retrieve the MPE elements
105 // that conform the LUT. It should be called with the LUT, the number of expected elements and
106 // then a list of expected types followed with a list of cmsFloat64Number pointers to MPE elements. If
107 // the function founds a match with current pipeline, it fills the pointers and returns TRUE
108 // if not, returns FALSE without touching anything. Setting pointers to NULL does bypass
109 // the storage process.
110 cmsBool CMSEXPORT cmsPipelineCheckAndRetreiveStages(const cmsPipeline* Lut, cmsUInt32Number n, ...)
115 cmsStageSignature Type;
118 // Make sure same number of elements
119 if (cmsPipelineStageCount(Lut) != n) return FALSE;
123 // Iterate across asked types
124 mpe = Lut ->Elements;
125 for (i=0; i < n; i++) {
128 Type = (cmsStageSignature)va_arg(args, cmsStageSignature);
129 if (mpe ->Type != Type) {
131 va_end(args); // Mismatch. We are done.
137 // Found a combination, fill pointers if not NULL
138 mpe = Lut ->Elements;
139 for (i=0; i < n; i++) {
141 ElemPtr = va_arg(args, void**);
152 // Below there are implementations for several types of elements. Each type may be implemented by a
153 // evaluation function, a duplication function, a function to free resources and a constructor.
155 // *************************************************************************************************
156 // Type cmsSigCurveSetElemType (curves)
157 // *************************************************************************************************
159 cmsToneCurve** _cmsStageGetPtrToCurveSet(const cmsStage* mpe)
161 _cmsStageToneCurvesData* Data = (_cmsStageToneCurvesData*) mpe ->Data;
163 return Data ->TheCurves;
167 void EvaluateCurves(const cmsFloat32Number In[],
168 cmsFloat32Number Out[],
171 _cmsStageToneCurvesData* Data;
174 _cmsAssert(mpe != NULL);
176 Data = (_cmsStageToneCurvesData*) mpe ->Data;
177 if (Data == NULL) return;
179 if (Data ->TheCurves == NULL) return;
181 for (i=0; i < Data ->nCurves; i++) {
182 Out[i] = cmsEvalToneCurveFloat(Data ->TheCurves[i], In[i]);
187 void CurveSetElemTypeFree(cmsStage* mpe)
189 _cmsStageToneCurvesData* Data;
192 _cmsAssert(mpe != NULL);
194 Data = (_cmsStageToneCurvesData*) mpe ->Data;
195 if (Data == NULL) return;
197 if (Data ->TheCurves != NULL) {
198 for (i=0; i < Data ->nCurves; i++) {
199 if (Data ->TheCurves[i] != NULL)
200 cmsFreeToneCurve(Data ->TheCurves[i]);
203 _cmsFree(mpe ->ContextID, Data ->TheCurves);
204 _cmsFree(mpe ->ContextID, Data);
209 void* CurveSetDup(cmsStage* mpe)
211 _cmsStageToneCurvesData* Data = (_cmsStageToneCurvesData*) mpe ->Data;
212 _cmsStageToneCurvesData* NewElem;
215 NewElem = (_cmsStageToneCurvesData*) _cmsMallocZero(mpe ->ContextID, sizeof(_cmsStageToneCurvesData));
216 if (NewElem == NULL) return NULL;
218 NewElem ->nCurves = Data ->nCurves;
219 NewElem ->TheCurves = (cmsToneCurve**) _cmsCalloc(mpe ->ContextID, NewElem ->nCurves, sizeof(cmsToneCurve*));
221 if (NewElem ->TheCurves == NULL) goto Error;
223 for (i=0; i < NewElem ->nCurves; i++) {
225 // Duplicate each curve. It may fail.
226 NewElem ->TheCurves[i] = cmsDupToneCurve(Data ->TheCurves[i]);
227 if (NewElem ->TheCurves[i] == NULL) goto Error;
231 return (void*) NewElem;
235 if (NewElem ->TheCurves != NULL) {
236 for (i=0; i < NewElem ->nCurves; i++) {
237 if (NewElem ->TheCurves[i])
238 cmsFreeToneCurve(Data ->TheCurves[i]);
241 _cmsFree(mpe ->ContextID, Data ->TheCurves);
242 _cmsFree(mpe ->ContextID, NewElem);
247 // Curves == NULL forces identity curves
248 cmsStage* CMSEXPORT cmsStageAllocToneCurves(cmsContext ContextID, cmsUInt32Number nChannels, cmsToneCurve* const Curves[])
251 _cmsStageToneCurvesData* NewElem;
255 NewMPE = _cmsStageAllocPlaceholder(ContextID, cmsSigCurveSetElemType, nChannels, nChannels,
256 EvaluateCurves, CurveSetDup, CurveSetElemTypeFree, NULL );
257 if (NewMPE == NULL) return NULL;
259 NewElem = (_cmsStageToneCurvesData*) _cmsMallocZero(ContextID, sizeof(_cmsStageToneCurvesData));
260 if (NewElem == NULL) {
261 cmsStageFree(NewMPE);
265 NewMPE ->Data = (void*) NewElem;
267 NewElem ->nCurves = nChannels;
268 NewElem ->TheCurves = (cmsToneCurve**) _cmsCalloc(ContextID, nChannels, sizeof(cmsToneCurve*));
269 if (NewElem ->TheCurves == NULL) {
270 cmsStageFree(NewMPE);
274 for (i=0; i < nChannels; i++) {
276 if (Curves == NULL) {
277 NewElem ->TheCurves[i] = cmsBuildGamma(ContextID, 1.0);
280 NewElem ->TheCurves[i] = cmsDupToneCurve(Curves[i]);
283 if (NewElem ->TheCurves[i] == NULL) {
284 cmsStageFree(NewMPE);
293 // Create a bunch of identity curves
294 cmsStage* _cmsStageAllocIdentityCurves(cmsContext ContextID, int nChannels)
296 cmsStage* mpe = cmsStageAllocToneCurves(ContextID, nChannels, NULL);
298 if (mpe == NULL) return NULL;
299 mpe ->Implements = cmsSigIdentityElemType;
304 // *************************************************************************************************
305 // Type cmsSigMatrixElemType (Matrices)
306 // *************************************************************************************************
309 // Special care should be taken here because precision loss. A temporary cmsFloat64Number buffer is being used
311 void EvaluateMatrix(const cmsFloat32Number In[],
312 cmsFloat32Number Out[],
315 cmsUInt32Number i, j;
316 _cmsStageMatrixData* Data = (_cmsStageMatrixData*) mpe ->Data;
317 cmsFloat64Number Tmp;
319 // Input is already in 0..1.0 notation
320 for (i=0; i < mpe ->OutputChannels; i++) {
323 for (j=0; j < mpe->InputChannels; j++) {
324 Tmp += In[j] * Data->Double[i*mpe->InputChannels + j];
327 if (Data ->Offset != NULL)
328 Tmp += Data->Offset[i];
330 Out[i] = (cmsFloat32Number) Tmp;
334 // Output in 0..1.0 domain
338 // Duplicate a yet-existing matrix element
340 void* MatrixElemDup(cmsStage* mpe)
342 _cmsStageMatrixData* Data = (_cmsStageMatrixData*) mpe ->Data;
343 _cmsStageMatrixData* NewElem;
346 NewElem = (_cmsStageMatrixData*) _cmsMallocZero(mpe ->ContextID, sizeof(_cmsStageMatrixData));
347 if (NewElem == NULL) return NULL;
349 sz = mpe ->InputChannels * mpe ->OutputChannels;
351 NewElem ->Double = (cmsFloat64Number*) _cmsDupMem(mpe ->ContextID, Data ->Double, sz * sizeof(cmsFloat64Number)) ;
354 NewElem ->Offset = (cmsFloat64Number*) _cmsDupMem(mpe ->ContextID,
355 Data ->Offset, mpe -> OutputChannels * sizeof(cmsFloat64Number)) ;
357 return (void*) NewElem;
362 void MatrixElemTypeFree(cmsStage* mpe)
364 _cmsStageMatrixData* Data = (_cmsStageMatrixData*) mpe ->Data;
366 _cmsFree(mpe ->ContextID, Data ->Double);
369 _cmsFree(mpe ->ContextID, Data ->Offset);
371 _cmsFree(mpe ->ContextID, mpe ->Data);
376 cmsStage* CMSEXPORT cmsStageAllocMatrix(cmsContext ContextID, cmsUInt32Number Rows, cmsUInt32Number Cols,
377 const cmsFloat64Number* Matrix, const cmsFloat64Number* Offset)
379 cmsUInt32Number i, n;
380 _cmsStageMatrixData* NewElem;
385 // Check for overflow
386 if (n == 0) return NULL;
387 if (n >= UINT_MAX / Cols) return NULL;
388 if (n >= UINT_MAX / Rows) return NULL;
389 if (n < Rows || n < Cols) return NULL;
391 NewMPE = _cmsStageAllocPlaceholder(ContextID, cmsSigMatrixElemType, Cols, Rows,
392 EvaluateMatrix, MatrixElemDup, MatrixElemTypeFree, NULL );
393 if (NewMPE == NULL) return NULL;
396 NewElem = (_cmsStageMatrixData*) _cmsMallocZero(ContextID, sizeof(_cmsStageMatrixData));
397 if (NewElem == NULL) return NULL;
400 NewElem ->Double = (cmsFloat64Number*) _cmsCalloc(ContextID, n, sizeof(cmsFloat64Number));
402 if (NewElem->Double == NULL) {
403 MatrixElemTypeFree(NewMPE);
407 for (i=0; i < n; i++) {
408 NewElem ->Double[i] = Matrix[i];
412 if (Offset != NULL) {
414 NewElem ->Offset = (cmsFloat64Number*) _cmsCalloc(ContextID, Cols, sizeof(cmsFloat64Number));
415 if (NewElem->Offset == NULL) {
416 MatrixElemTypeFree(NewMPE);
420 for (i=0; i < Cols; i++) {
421 NewElem ->Offset[i] = Offset[i];
426 NewMPE ->Data = (void*) NewElem;
431 // *************************************************************************************************
432 // Type cmsSigCLutElemType
433 // *************************************************************************************************
436 // Evaluate in true floating point
438 void EvaluateCLUTfloat(const cmsFloat32Number In[], cmsFloat32Number Out[], const cmsStage *mpe)
440 _cmsStageCLutData* Data = (_cmsStageCLutData*) mpe ->Data;
442 Data -> Params ->Interpolation.LerpFloat(In, Out, Data->Params);
446 // Convert to 16 bits, evaluate, and back to floating point
448 void EvaluateCLUTfloatIn16(const cmsFloat32Number In[], cmsFloat32Number Out[], const cmsStage *mpe)
450 _cmsStageCLutData* Data = (_cmsStageCLutData*) mpe ->Data;
451 cmsUInt16Number In16[MAX_STAGE_CHANNELS], Out16[MAX_STAGE_CHANNELS];
453 _cmsAssert(mpe ->InputChannels <= MAX_STAGE_CHANNELS);
454 _cmsAssert(mpe ->OutputChannels <= MAX_STAGE_CHANNELS);
456 FromFloatTo16(In, In16, mpe ->InputChannels);
457 Data -> Params ->Interpolation.Lerp16(In16, Out16, Data->Params);
458 From16ToFloat(Out16, Out, mpe ->OutputChannels);
462 // Given an hypercube of b dimensions, with Dims[] number of nodes by dimension, calculate the total amount of nodes
464 cmsUInt32Number CubeSize(const cmsUInt32Number Dims[], cmsUInt32Number b)
466 cmsUInt32Number rv, dim;
468 _cmsAssert(Dims != NULL);
470 for (rv = 1; b > 0; b--) {
473 if (dim == 0) return 0; // Error
477 // Check for overflow
478 if (rv > UINT_MAX / dim) return 0;
485 void* CLUTElemDup(cmsStage* mpe)
487 _cmsStageCLutData* Data = (_cmsStageCLutData*) mpe ->Data;
488 _cmsStageCLutData* NewElem;
491 NewElem = (_cmsStageCLutData*) _cmsMallocZero(mpe ->ContextID, sizeof(_cmsStageCLutData));
492 if (NewElem == NULL) return NULL;
494 NewElem ->nEntries = Data ->nEntries;
495 NewElem ->HasFloatValues = Data ->HasFloatValues;
499 if (Data ->HasFloatValues)
500 NewElem ->Tab.TFloat = (cmsFloat32Number*) _cmsDupMem(mpe ->ContextID, Data ->Tab.TFloat, Data ->nEntries * sizeof (cmsFloat32Number));
502 NewElem ->Tab.T = (cmsUInt16Number*) _cmsDupMem(mpe ->ContextID, Data ->Tab.T, Data ->nEntries * sizeof (cmsUInt16Number));
505 NewElem ->Params = _cmsComputeInterpParamsEx(mpe ->ContextID,
506 Data ->Params ->nSamples,
507 Data ->Params ->nInputs,
508 Data ->Params ->nOutputs,
510 Data ->Params ->dwFlags);
512 return (void*) NewElem;
517 void CLutElemTypeFree(cmsStage* mpe)
520 _cmsStageCLutData* Data = (_cmsStageCLutData*) mpe ->Data;
523 if (Data == NULL) return;
525 // This works for both types
527 _cmsFree(mpe ->ContextID, Data -> Tab.T);
529 _cmsFreeInterpParams(Data ->Params);
530 _cmsFree(mpe ->ContextID, mpe ->Data);
534 // Allocates a 16-bit multidimensional CLUT. This is evaluated at 16-bit precision. Table may have different
535 // granularity on each dimension.
536 cmsStage* CMSEXPORT cmsStageAllocCLut16bitGranular(cmsContext ContextID,
537 const cmsUInt32Number clutPoints[],
538 cmsUInt32Number inputChan,
539 cmsUInt32Number outputChan,
540 const cmsUInt16Number* Table)
542 cmsUInt32Number i, n;
543 _cmsStageCLutData* NewElem;
546 NewMPE = _cmsStageAllocPlaceholder(ContextID, cmsSigCLutElemType, inputChan, outputChan,
547 EvaluateCLUTfloatIn16, CLUTElemDup, CLutElemTypeFree, NULL );
549 if (NewMPE == NULL) return NULL;
551 NewElem = (_cmsStageCLutData*) _cmsMallocZero(ContextID, sizeof(_cmsStageCLutData));
552 if (NewElem == NULL) {
553 cmsStageFree(NewMPE);
557 NewMPE ->Data = (void*) NewElem;
559 NewElem -> nEntries = n = outputChan * CubeSize(clutPoints, inputChan);
560 NewElem -> HasFloatValues = FALSE;
563 cmsStageFree(NewMPE);
568 NewElem ->Tab.T = (cmsUInt16Number*) _cmsCalloc(ContextID, n, sizeof(cmsUInt16Number));
569 if (NewElem ->Tab.T == NULL) {
570 cmsStageFree(NewMPE);
575 for (i=0; i < n; i++) {
576 NewElem ->Tab.T[i] = Table[i];
580 NewElem ->Params = _cmsComputeInterpParamsEx(ContextID, clutPoints, inputChan, outputChan, NewElem ->Tab.T, CMS_LERP_FLAGS_16BITS);
581 if (NewElem ->Params == NULL) {
582 cmsStageFree(NewMPE);
589 cmsStage* CMSEXPORT cmsStageAllocCLut16bit(cmsContext ContextID,
590 cmsUInt32Number nGridPoints,
591 cmsUInt32Number inputChan,
592 cmsUInt32Number outputChan,
593 const cmsUInt16Number* Table)
595 cmsUInt32Number Dimensions[MAX_INPUT_DIMENSIONS];
598 // Our resulting LUT would be same gridpoints on all dimensions
599 for (i=0; i < MAX_INPUT_DIMENSIONS; i++)
600 Dimensions[i] = nGridPoints;
603 return cmsStageAllocCLut16bitGranular(ContextID, Dimensions, inputChan, outputChan, Table);
607 cmsStage* CMSEXPORT cmsStageAllocCLutFloat(cmsContext ContextID,
608 cmsUInt32Number nGridPoints,
609 cmsUInt32Number inputChan,
610 cmsUInt32Number outputChan,
611 const cmsFloat32Number* Table)
613 cmsUInt32Number Dimensions[MAX_INPUT_DIMENSIONS];
616 // Our resulting LUT would be same gridpoints on all dimensions
617 for (i=0; i < MAX_INPUT_DIMENSIONS; i++)
618 Dimensions[i] = nGridPoints;
620 return cmsStageAllocCLutFloatGranular(ContextID, Dimensions, inputChan, outputChan, Table);
625 cmsStage* CMSEXPORT cmsStageAllocCLutFloatGranular(cmsContext ContextID, const cmsUInt32Number clutPoints[], cmsUInt32Number inputChan, cmsUInt32Number outputChan, const cmsFloat32Number* Table)
627 cmsUInt32Number i, n;
628 _cmsStageCLutData* NewElem;
631 _cmsAssert(clutPoints != NULL);
633 NewMPE = _cmsStageAllocPlaceholder(ContextID, cmsSigCLutElemType, inputChan, outputChan,
634 EvaluateCLUTfloat, CLUTElemDup, CLutElemTypeFree, NULL);
635 if (NewMPE == NULL) return NULL;
638 NewElem = (_cmsStageCLutData*) _cmsMallocZero(ContextID, sizeof(_cmsStageCLutData));
639 if (NewElem == NULL) {
640 cmsStageFree(NewMPE);
644 NewMPE ->Data = (void*) NewElem;
646 // There is a potential integer overflow on conputing n and nEntries.
647 NewElem -> nEntries = n = outputChan * CubeSize(clutPoints, inputChan);
648 NewElem -> HasFloatValues = TRUE;
651 cmsStageFree(NewMPE);
655 NewElem ->Tab.TFloat = (cmsFloat32Number*) _cmsCalloc(ContextID, n, sizeof(cmsFloat32Number));
656 if (NewElem ->Tab.TFloat == NULL) {
657 cmsStageFree(NewMPE);
662 for (i=0; i < n; i++) {
663 NewElem ->Tab.TFloat[i] = Table[i];
669 NewElem ->Params = _cmsComputeInterpParamsEx(ContextID, clutPoints, inputChan, outputChan, NewElem ->Tab.TFloat, CMS_LERP_FLAGS_FLOAT);
670 if (NewElem ->Params == NULL) {
671 cmsStageFree(NewMPE);
682 int IdentitySampler(register const cmsUInt16Number In[], register cmsUInt16Number Out[], register void * Cargo)
684 int nChan = *(int*) Cargo;
687 for (i=0; i < nChan; i++)
693 // Creates an MPE that just copies input to output
694 cmsStage* _cmsStageAllocIdentityCLut(cmsContext ContextID, int nChan)
696 cmsUInt32Number Dimensions[MAX_INPUT_DIMENSIONS];
700 for (i=0; i < MAX_INPUT_DIMENSIONS; i++)
703 mpe = cmsStageAllocCLut16bitGranular(ContextID, Dimensions, nChan, nChan, NULL);
704 if (mpe == NULL) return NULL;
706 if (!cmsStageSampleCLut16bit(mpe, IdentitySampler, &nChan, 0)) {
711 mpe ->Implements = cmsSigIdentityElemType;
717 // Quantize a value 0 <= i < MaxSamples to 0..0xffff
718 cmsUInt16Number _cmsQuantizeVal(cmsFloat64Number i, int MaxSamples)
722 x = ((cmsFloat64Number) i * 65535.) / (cmsFloat64Number) (MaxSamples - 1);
723 return _cmsQuickSaturateWord(x);
727 // This routine does a sweep on whole input space, and calls its callback
728 // function on knots. returns TRUE if all ok, FALSE otherwise.
729 cmsBool CMSEXPORT cmsStageSampleCLut16bit(cmsStage* mpe, cmsSAMPLER16 Sampler, void * Cargo, cmsUInt32Number dwFlags)
731 int i, t, nTotalPoints, index, rest;
732 int nInputs, nOutputs;
733 cmsUInt32Number* nSamples;
734 cmsUInt16Number In[cmsMAXCHANNELS], Out[MAX_STAGE_CHANNELS];
735 _cmsStageCLutData* clut;
737 if (mpe == NULL) return FALSE;
739 clut = (_cmsStageCLutData*) mpe->Data;
741 if (clut == NULL) return FALSE;
743 nSamples = clut->Params ->nSamples;
744 nInputs = clut->Params ->nInputs;
745 nOutputs = clut->Params ->nOutputs;
747 if (nInputs >= cmsMAXCHANNELS) return FALSE;
748 if (nOutputs >= MAX_STAGE_CHANNELS) return FALSE;
750 nTotalPoints = CubeSize(nSamples, nInputs);
751 if (nTotalPoints == 0) return FALSE;
754 for (i = 0; i < nTotalPoints; i++) {
757 for (t = nInputs-1; t >=0; --t) {
759 cmsUInt32Number Colorant = rest % nSamples[t];
763 In[t] = _cmsQuantizeVal(Colorant, nSamples[t]);
766 if (clut ->Tab.T != NULL) {
767 for (t=0; t < nOutputs; t++)
768 Out[t] = clut->Tab.T[index + t];
771 if (!Sampler(In, Out, Cargo))
774 if (!(dwFlags & SAMPLER_INSPECT)) {
776 if (clut ->Tab.T != NULL) {
777 for (t=0; t < nOutputs; t++)
778 clut->Tab.T[index + t] = Out[t];
788 // Same as anterior, but for floting point
789 cmsBool CMSEXPORT cmsStageSampleCLutFloat(cmsStage* mpe, cmsSAMPLERFLOAT Sampler, void * Cargo, cmsUInt32Number dwFlags)
791 int i, t, nTotalPoints, index, rest;
792 int nInputs, nOutputs;
793 cmsUInt32Number* nSamples;
794 cmsFloat32Number In[cmsMAXCHANNELS], Out[MAX_STAGE_CHANNELS];
795 _cmsStageCLutData* clut = (_cmsStageCLutData*) mpe->Data;
797 nSamples = clut->Params ->nSamples;
798 nInputs = clut->Params ->nInputs;
799 nOutputs = clut->Params ->nOutputs;
801 if (nInputs >= cmsMAXCHANNELS) return FALSE;
802 if (nOutputs >= MAX_STAGE_CHANNELS) return FALSE;
804 nTotalPoints = CubeSize(nSamples, nInputs);
805 if (nTotalPoints == 0) return FALSE;
808 for (i = 0; i < nTotalPoints; i++) {
811 for (t = nInputs-1; t >=0; --t) {
813 cmsUInt32Number Colorant = rest % nSamples[t];
817 In[t] = (cmsFloat32Number) (_cmsQuantizeVal(Colorant, nSamples[t]) / 65535.0);
820 if (clut ->Tab.TFloat != NULL) {
821 for (t=0; t < nOutputs; t++)
822 Out[t] = clut->Tab.TFloat[index + t];
825 if (!Sampler(In, Out, Cargo))
828 if (!(dwFlags & SAMPLER_INSPECT)) {
830 if (clut ->Tab.TFloat != NULL) {
831 for (t=0; t < nOutputs; t++)
832 clut->Tab.TFloat[index + t] = Out[t];
844 // This routine does a sweep on whole input space, and calls its callback
845 // function on knots. returns TRUE if all ok, FALSE otherwise.
846 cmsBool CMSEXPORT cmsSliceSpace16(cmsUInt32Number nInputs, const cmsUInt32Number clutPoints[],
847 cmsSAMPLER16 Sampler, void * Cargo)
849 int i, t, nTotalPoints, rest;
850 cmsUInt16Number In[cmsMAXCHANNELS];
852 if (nInputs >= cmsMAXCHANNELS) return FALSE;
854 nTotalPoints = CubeSize(clutPoints, nInputs);
855 if (nTotalPoints == 0) return FALSE;
857 for (i = 0; i < nTotalPoints; i++) {
860 for (t = nInputs-1; t >=0; --t) {
862 cmsUInt32Number Colorant = rest % clutPoints[t];
864 rest /= clutPoints[t];
865 In[t] = _cmsQuantizeVal(Colorant, clutPoints[t]);
869 if (!Sampler(In, NULL, Cargo))
876 cmsInt32Number CMSEXPORT cmsSliceSpaceFloat(cmsUInt32Number nInputs, const cmsUInt32Number clutPoints[],
877 cmsSAMPLERFLOAT Sampler, void * Cargo)
879 int i, t, nTotalPoints, rest;
880 cmsFloat32Number In[cmsMAXCHANNELS];
882 if (nInputs >= cmsMAXCHANNELS) return FALSE;
884 nTotalPoints = CubeSize(clutPoints, nInputs);
885 if (nTotalPoints == 0) return FALSE;
887 for (i = 0; i < nTotalPoints; i++) {
890 for (t = nInputs-1; t >=0; --t) {
892 cmsUInt32Number Colorant = rest % clutPoints[t];
894 rest /= clutPoints[t];
895 In[t] = (cmsFloat32Number) (_cmsQuantizeVal(Colorant, clutPoints[t]) / 65535.0);
899 if (!Sampler(In, NULL, Cargo))
906 // ********************************************************************************
907 // Type cmsSigLab2XYZElemType
908 // ********************************************************************************
912 void EvaluateLab2XYZ(const cmsFloat32Number In[],
913 cmsFloat32Number Out[],
918 const cmsFloat64Number XYZadj = MAX_ENCODEABLE_XYZ;
921 Lab.L = In[0] * 100.0;
922 Lab.a = In[1] * 255.0 - 128.0;
923 Lab.b = In[2] * 255.0 - 128.0;
925 cmsLab2XYZ(NULL, &XYZ, &Lab);
927 // From XYZ, range 0..19997 to 0..1.0, note that 1.99997 comes from 0xffff
928 // encoded as 1.15 fixed point, so 1 + (32767.0 / 32768.0)
930 Out[0] = (cmsFloat32Number) ((cmsFloat64Number) XYZ.X / XYZadj);
931 Out[1] = (cmsFloat32Number) ((cmsFloat64Number) XYZ.Y / XYZadj);
932 Out[2] = (cmsFloat32Number) ((cmsFloat64Number) XYZ.Z / XYZadj);
935 cmsUNUSED_PARAMETER(mpe);
939 // No dup or free routines needed, as the structure has no pointers in it.
940 cmsStage* _cmsStageAllocLab2XYZ(cmsContext ContextID)
942 return _cmsStageAllocPlaceholder(ContextID, cmsSigLab2XYZElemType, 3, 3, EvaluateLab2XYZ, NULL, NULL, NULL);
945 // ********************************************************************************
947 // v2 L=100 is supposed to be placed on 0xFF00. There is no reasonable
948 // number of gridpoints that would make exact match. However, a prelinearization
949 // of 258 entries, would map 0xFF00 exactly on entry 257, and this is good to avoid scum dot.
950 // Almost all what we need but unfortunately, the rest of entries should be scaled by
951 // (255*257/256) and this is not exact.
953 cmsStage* _cmsStageAllocLabV2ToV4curves(cmsContext ContextID)
956 cmsToneCurve* LabTable[3];
959 LabTable[0] = cmsBuildTabulatedToneCurve16(ContextID, 258, NULL);
960 LabTable[1] = cmsBuildTabulatedToneCurve16(ContextID, 258, NULL);
961 LabTable[2] = cmsBuildTabulatedToneCurve16(ContextID, 258, NULL);
963 for (j=0; j < 3; j++) {
965 if (LabTable[j] == NULL) {
966 cmsFreeToneCurveTriple(LabTable);
970 // We need to map * (0xffff / 0xff00), thats same as (257 / 256)
971 // So we can use 258-entry tables to do the trick (i / 257) * (255 * 257) * (257 / 256);
972 for (i=0; i < 257; i++) {
974 LabTable[j]->Table16[i] = (cmsUInt16Number) ((i * 0xffff + 0x80) >> 8);
977 LabTable[j] ->Table16[257] = 0xffff;
980 mpe = cmsStageAllocToneCurves(ContextID, 3, LabTable);
981 cmsFreeToneCurveTriple(LabTable);
983 mpe ->Implements = cmsSigLabV2toV4;
987 // ********************************************************************************
989 // Matrix-based conversion, which is more accurate, but slower and cannot properly be saved in devicelink profiles
990 cmsStage* _cmsStageAllocLabV2ToV4(cmsContext ContextID)
992 static const cmsFloat64Number V2ToV4[] = { 65535.0/65280.0, 0, 0,
993 0, 65535.0/65280.0, 0,
994 0, 0, 65535.0/65280.0
997 cmsStage *mpe = cmsStageAllocMatrix(ContextID, 3, 3, V2ToV4, NULL);
999 if (mpe == NULL) return mpe;
1000 mpe ->Implements = cmsSigLabV2toV4;
1005 // Reverse direction
1006 cmsStage* _cmsStageAllocLabV4ToV2(cmsContext ContextID)
1008 static const cmsFloat64Number V4ToV2[] = { 65280.0/65535.0, 0, 0,
1009 0, 65280.0/65535.0, 0,
1010 0, 0, 65280.0/65535.0
1013 cmsStage *mpe = cmsStageAllocMatrix(ContextID, 3, 3, V4ToV2, NULL);
1015 if (mpe == NULL) return mpe;
1016 mpe ->Implements = cmsSigLabV4toV2;
1021 // To Lab to float. Note that the MPE gives numbers in normal Lab range
1022 // and we need 0..1.0 range for the formatters
1023 // L* : 0...100 => 0...1.0 (L* / 100)
1024 // ab* : -128..+127 to 0..1 ((ab* + 128) / 255)
1026 cmsStage* _cmsStageNormalizeFromLabFloat(cmsContext ContextID)
1028 static const cmsFloat64Number a1[] = {
1034 static const cmsFloat64Number o1[] = {
1040 return cmsStageAllocMatrix(ContextID, 3, 3, a1, o1);
1043 cmsStage* _cmsStageNormalizeFromXyzFloat(cmsContext ContextID)
1045 static const cmsFloat64Number a1[] = {
1052 return cmsStageAllocMatrix(ContextID, 3, 3, a1, NULL);
1055 cmsStage* _cmsStageNormalizeToLabFloat(cmsContext ContextID)
1057 static const cmsFloat64Number a1[] = {
1063 static const cmsFloat64Number o1[] = {
1069 return cmsStageAllocMatrix(ContextID, 3, 3, a1, o1);
1072 cmsStage* _cmsStageNormalizeToXyzFloat(cmsContext ContextID)
1074 static const cmsFloat64Number a1[] = {
1080 return cmsStageAllocMatrix(ContextID, 3, 3, a1, NULL);
1085 // ********************************************************************************
1086 // Type cmsSigXYZ2LabElemType
1087 // ********************************************************************************
1090 void EvaluateXYZ2Lab(const cmsFloat32Number In[], cmsFloat32Number Out[], const cmsStage *mpe)
1094 const cmsFloat64Number XYZadj = MAX_ENCODEABLE_XYZ;
1096 // From 0..1.0 to XYZ
1098 XYZ.X = In[0] * XYZadj;
1099 XYZ.Y = In[1] * XYZadj;
1100 XYZ.Z = In[2] * XYZadj;
1102 cmsXYZ2Lab(NULL, &Lab, &XYZ);
1104 // From V4 Lab to 0..1.0
1106 Out[0] = (cmsFloat32Number) (Lab.L / 100.0);
1107 Out[1] = (cmsFloat32Number) ((Lab.a + 128.0) / 255.0);
1108 Out[2] = (cmsFloat32Number) ((Lab.b + 128.0) / 255.0);
1111 cmsUNUSED_PARAMETER(mpe);
1114 cmsStage* _cmsStageAllocXYZ2Lab(cmsContext ContextID)
1116 return _cmsStageAllocPlaceholder(ContextID, cmsSigXYZ2LabElemType, 3, 3, EvaluateXYZ2Lab, NULL, NULL, NULL);
1120 // ********************************************************************************
1122 // For v4, S-Shaped curves are placed in a/b axis to increase resolution near gray
1124 cmsStage* _cmsStageAllocLabPrelin(cmsContext ContextID)
1126 cmsToneCurve* LabTable[3];
1127 cmsFloat64Number Params[1] = {2.4} ;
1129 LabTable[0] = cmsBuildGamma(ContextID, 1.0);
1130 LabTable[1] = cmsBuildParametricToneCurve(ContextID, 108, Params);
1131 LabTable[2] = cmsBuildParametricToneCurve(ContextID, 108, Params);
1133 return cmsStageAllocToneCurves(ContextID, 3, LabTable);
1137 // Free a single MPE
1138 void CMSEXPORT cmsStageFree(cmsStage* mpe)
1143 _cmsFree(mpe ->ContextID, mpe);
1147 cmsUInt32Number CMSEXPORT cmsStageInputChannels(const cmsStage* mpe)
1149 return mpe ->InputChannels;
1152 cmsUInt32Number CMSEXPORT cmsStageOutputChannels(const cmsStage* mpe)
1154 return mpe ->OutputChannels;
1157 cmsStageSignature CMSEXPORT cmsStageType(const cmsStage* mpe)
1162 void* CMSEXPORT cmsStageData(const cmsStage* mpe)
1167 cmsStage* CMSEXPORT cmsStageNext(const cmsStage* mpe)
1173 // Duplicates an MPE
1174 cmsStage* CMSEXPORT cmsStageDup(cmsStage* mpe)
1178 if (mpe == NULL) return NULL;
1179 NewMPE = _cmsStageAllocPlaceholder(mpe ->ContextID,
1181 mpe ->InputChannels,
1182 mpe ->OutputChannels,
1187 if (NewMPE == NULL) return NULL;
1189 NewMPE ->Implements = mpe ->Implements;
1191 if (mpe ->DupElemPtr)
1192 NewMPE ->Data = mpe ->DupElemPtr(mpe);
1194 NewMPE ->Data = NULL;
1200 // ***********************************************************************************************************
1202 // This function sets up the channel count
1205 void BlessLUT(cmsPipeline* lut)
1207 // We can set the input/ouput channels only if we have elements.
1208 if (lut ->Elements != NULL) {
1210 cmsStage *First, *Last;
1212 First = cmsPipelineGetPtrToFirstStage(lut);
1213 Last = cmsPipelineGetPtrToLastStage(lut);
1215 if (First != NULL)lut ->InputChannels = First ->InputChannels;
1216 if (Last != NULL) lut ->OutputChannels = Last ->OutputChannels;
1221 // Default to evaluate the LUT on 16 bit-basis. Precision is retained.
1223 void _LUTeval16(register const cmsUInt16Number In[], register cmsUInt16Number Out[], register const void* D)
1225 cmsPipeline* lut = (cmsPipeline*) D;
1227 cmsFloat32Number Storage[2][MAX_STAGE_CHANNELS];
1228 int Phase = 0, NextPhase;
1230 From16ToFloat(In, &Storage[Phase][0], lut ->InputChannels);
1232 for (mpe = lut ->Elements;
1236 NextPhase = Phase ^ 1;
1237 mpe ->EvalPtr(&Storage[Phase][0], &Storage[NextPhase][0], mpe);
1242 FromFloatTo16(&Storage[Phase][0], Out, lut ->OutputChannels);
1247 // Does evaluate the LUT on cmsFloat32Number-basis.
1249 void _LUTevalFloat(register const cmsFloat32Number In[], register cmsFloat32Number Out[], const void* D)
1251 cmsPipeline* lut = (cmsPipeline*) D;
1253 cmsFloat32Number Storage[2][MAX_STAGE_CHANNELS];
1254 int Phase = 0, NextPhase;
1256 memmove(&Storage[Phase][0], In, lut ->InputChannels * sizeof(cmsFloat32Number));
1258 for (mpe = lut ->Elements;
1262 NextPhase = Phase ^ 1;
1263 mpe ->EvalPtr(&Storage[Phase][0], &Storage[NextPhase][0], mpe);
1267 memmove(Out, &Storage[Phase][0], lut ->OutputChannels * sizeof(cmsFloat32Number));
1273 // LUT Creation & Destruction
1275 cmsPipeline* CMSEXPORT cmsPipelineAlloc(cmsContext ContextID, cmsUInt32Number InputChannels, cmsUInt32Number OutputChannels)
1277 cmsPipeline* NewLUT;
1279 if (InputChannels >= cmsMAXCHANNELS ||
1280 OutputChannels >= cmsMAXCHANNELS) return NULL;
1282 NewLUT = (cmsPipeline*) _cmsMallocZero(ContextID, sizeof(cmsPipeline));
1283 if (NewLUT == NULL) return NULL;
1286 NewLUT -> InputChannels = InputChannels;
1287 NewLUT -> OutputChannels = OutputChannels;
1289 NewLUT ->Eval16Fn = _LUTeval16;
1290 NewLUT ->EvalFloatFn = _LUTevalFloat;
1291 NewLUT ->DupDataFn = NULL;
1292 NewLUT ->FreeDataFn = NULL;
1293 NewLUT ->Data = NewLUT;
1294 NewLUT ->ContextID = ContextID;
1302 cmsUInt32Number CMSEXPORT cmsPipelineInputChannels(const cmsPipeline* lut)
1304 return lut ->InputChannels;
1307 cmsUInt32Number CMSEXPORT cmsPipelineOutputChannels(const cmsPipeline* lut)
1309 return lut ->OutputChannels;
1312 // Free a profile elements LUT
1313 void CMSEXPORT cmsPipelineFree(cmsPipeline* lut)
1315 cmsStage *mpe, *Next;
1317 if (lut == NULL) return;
1319 for (mpe = lut ->Elements;
1327 if (lut ->FreeDataFn) lut ->FreeDataFn(lut ->ContextID, lut ->Data);
1329 _cmsFree(lut ->ContextID, lut);
1333 // Default to evaluate the LUT on 16 bit-basis.
1334 void CMSEXPORT cmsPipelineEval16(const cmsUInt16Number In[], cmsUInt16Number Out[], const cmsPipeline* lut)
1336 lut ->Eval16Fn(In, Out, lut->Data);
1340 // Does evaluate the LUT on cmsFloat32Number-basis.
1341 void CMSEXPORT cmsPipelineEvalFloat(const cmsFloat32Number In[], cmsFloat32Number Out[], const cmsPipeline* lut)
1343 lut ->EvalFloatFn(In, Out, lut);
1349 cmsPipeline* CMSEXPORT cmsPipelineDup(const cmsPipeline* lut)
1351 cmsPipeline* NewLUT;
1352 cmsStage *NewMPE, *Anterior = NULL, *mpe;
1353 cmsBool First = TRUE;
1355 if (lut == NULL) return NULL;
1357 NewLUT = cmsPipelineAlloc(lut ->ContextID, lut ->InputChannels, lut ->OutputChannels);
1358 for (mpe = lut ->Elements;
1362 NewMPE = cmsStageDup(mpe);
1364 if (NewMPE == NULL) {
1365 cmsPipelineFree(NewLUT);
1370 NewLUT ->Elements = NewMPE;
1374 Anterior ->Next = NewMPE;
1380 NewLUT ->DupDataFn = lut ->DupDataFn;
1381 NewLUT ->FreeDataFn = lut ->FreeDataFn;
1383 if (NewLUT ->DupDataFn != NULL)
1384 NewLUT ->Data = NewLUT ->DupDataFn(lut ->ContextID, lut->Data);
1387 NewLUT ->SaveAs8Bits = lut ->SaveAs8Bits;
1394 void CMSEXPORT cmsPipelineInsertStage(cmsPipeline* lut, cmsStageLoc loc, cmsStage* mpe)
1396 cmsStage* Anterior = NULL, *pt;
1398 _cmsAssert(lut != NULL);
1399 _cmsAssert(mpe != NULL);
1404 mpe ->Next = lut ->Elements;
1405 lut ->Elements = mpe;
1410 if (lut ->Elements == NULL)
1411 lut ->Elements = mpe;
1414 for (pt = lut ->Elements;
1416 pt = pt -> Next) Anterior = pt;
1418 Anterior ->Next = mpe;
1428 // Unlink an element and return the pointer to it
1429 void CMSEXPORT cmsPipelineUnlinkStage(cmsPipeline* lut, cmsStageLoc loc, cmsStage** mpe)
1431 cmsStage *Anterior, *pt, *Last;
1432 cmsStage *Unlinked = NULL;
1435 // If empty LUT, there is nothing to remove
1436 if (lut ->Elements == NULL) {
1437 if (mpe) *mpe = NULL;
1441 // On depending on the strategy...
1446 cmsStage* elem = lut ->Elements;
1448 lut ->Elements = elem -> Next;
1456 Anterior = Last = NULL;
1457 for (pt = lut ->Elements;
1464 Unlinked = Last; // Next already points to NULL
1466 // Truncate the chain
1468 Anterior ->Next = NULL;
1470 lut ->Elements = NULL;
1478 cmsStageFree(Unlinked);
1484 // Concatenate two LUT into a new single one
1485 cmsBool CMSEXPORT cmsPipelineCat(cmsPipeline* l1, const cmsPipeline* l2)
1487 cmsStage* mpe, *NewMPE;
1489 // If both LUTS does not have elements, we need to inherit
1490 // the number of channels
1491 if (l1 ->Elements == NULL && l2 ->Elements == NULL) {
1492 l1 ->InputChannels = l2 ->InputChannels;
1493 l1 ->OutputChannels = l2 ->OutputChannels;
1497 for (mpe = l2 ->Elements;
1501 // We have to dup each element
1502 NewMPE = cmsStageDup(mpe);
1504 if (NewMPE == NULL) {
1508 cmsPipelineInsertStage(l1, cmsAT_END, NewMPE);
1516 cmsBool CMSEXPORT cmsPipelineSetSaveAs8bitsFlag(cmsPipeline* lut, cmsBool On)
1518 cmsBool Anterior = lut ->SaveAs8Bits;
1520 lut ->SaveAs8Bits = On;
1525 cmsStage* CMSEXPORT cmsPipelineGetPtrToFirstStage(const cmsPipeline* lut)
1527 return lut ->Elements;
1530 cmsStage* CMSEXPORT cmsPipelineGetPtrToLastStage(const cmsPipeline* lut)
1532 cmsStage *mpe, *Anterior = NULL;
1534 for (mpe = lut ->Elements; mpe != NULL; mpe = mpe ->Next)
1540 cmsUInt32Number CMSEXPORT cmsPipelineStageCount(const cmsPipeline* lut)
1545 for (n=0, mpe = lut ->Elements; mpe != NULL; mpe = mpe ->Next)
1551 // This function may be used to set the optional evaluator and a block of private data. If private data is being used, an optional
1552 // duplicator and free functions should also be specified in order to duplicate the LUT construct. Use NULL to inhibit such functionality.
1553 void CMSEXPORT _cmsPipelineSetOptimizationParameters(cmsPipeline* Lut,
1554 _cmsOPTeval16Fn Eval16,
1556 _cmsOPTfreeDataFn FreePrivateDataFn,
1557 _cmsOPTdupDataFn DupPrivateDataFn)
1560 Lut ->Eval16Fn = Eval16;
1561 Lut ->DupDataFn = DupPrivateDataFn;
1562 Lut ->FreeDataFn = FreePrivateDataFn;
1563 Lut ->Data = PrivateData;
1567 // ----------------------------------------------------------- Reverse interpolation
1568 // Here's how it goes. The derivative Df(x) of the function f is the linear
1569 // transformation that best approximates f near the point x. It can be represented
1570 // by a matrix A whose entries are the partial derivatives of the components of f
1571 // with respect to all the coordinates. This is know as the Jacobian
1573 // The best linear approximation to f is given by the matrix equation:
1577 // So, if x0 is a good "guess" for the zero of f, then solving for the zero of this
1578 // linear approximation will give a "better guess" for the zero of f. Thus let y=0,
1579 // and since y0=f(x0) one can solve the above equation for x. This leads to the
1580 // Newton's method formula:
1582 // xn+1 = xn - A-1 f(xn)
1584 // where xn+1 denotes the (n+1)-st guess, obtained from the n-th guess xn in the
1585 // fashion described above. Iterating this will give better and better approximations
1586 // if you have a "good enough" initial guess.
1589 #define JACOBIAN_EPSILON 0.001f
1590 #define INVERSION_MAX_ITERATIONS 30
1592 // Increment with reflexion on boundary
1594 void IncDelta(cmsFloat32Number *Val)
1596 if (*Val < (1.0 - JACOBIAN_EPSILON))
1598 *Val += JACOBIAN_EPSILON;
1601 *Val -= JACOBIAN_EPSILON;
1607 // Euclidean distance between two vectors of n elements each one
1609 cmsFloat32Number EuclideanDistance(cmsFloat32Number a[], cmsFloat32Number b[], int n)
1611 cmsFloat32Number sum = 0;
1614 for (i=0; i < n; i++) {
1615 cmsFloat32Number dif = b[i] - a[i];
1623 // Evaluate a LUT in reverse direction. It only searches on 3->3 LUT. Uses Newton method
1625 // x1 <- x - [J(x)]^-1 * f(x)
1627 // lut: The LUT on where to do the search
1628 // Target: LabK, 3 values of Lab plus destination K which is fixed
1629 // Result: The obtained CMYK
1630 // Hint: Location where begin the search
1632 cmsBool CMSEXPORT cmsPipelineEvalReverseFloat(cmsFloat32Number Target[],
1633 cmsFloat32Number Result[],
1634 cmsFloat32Number Hint[],
1635 const cmsPipeline* lut)
1637 cmsUInt32Number i, j;
1638 cmsFloat64Number error, LastError = 1E20;
1639 cmsFloat32Number fx[4], x[4], xd[4], fxd[4];
1642 cmsFloat64Number LastResult[4];
1645 // Only 3->3 and 4->3 are supported
1646 if (lut ->InputChannels != 3 && lut ->InputChannels != 4) return FALSE;
1647 if (lut ->OutputChannels != 3) return FALSE;
1649 // Mark result of -1
1650 LastResult[0] = LastResult[1] = LastResult[2] = -1.0f;
1652 // Take the hint as starting point if specified
1655 // Begin at any point, we choose 1/3 of CMY axis
1656 x[0] = x[1] = x[2] = 0.3f;
1660 // Only copy 3 channels from hint...
1661 for (j=0; j < 3; j++)
1665 // If Lut is 4-dimensions, then grab target[3], which is fixed
1666 if (lut ->InputChannels == 4) {
1669 else x[3] = 0; // To keep lint happy
1673 for (i = 0; i < INVERSION_MAX_ITERATIONS; i++) {
1676 cmsPipelineEvalFloat(x, fx, lut);
1679 error = EuclideanDistance(fx, Target, 3);
1681 // If not convergent, return last safe value
1682 if (error >= LastError)
1685 // Keep latest values
1687 for (j=0; j < lut ->InputChannels; j++)
1690 // Found an exact match?
1694 // Obtain slope (the Jacobian)
1695 for (j = 0; j < 3; j++) {
1700 xd[3] = x[3]; // Keep fixed channel
1704 cmsPipelineEvalFloat(xd, fxd, lut);
1706 Jacobian.v[0].n[j] = ((fxd[0] - fx[0]) / JACOBIAN_EPSILON);
1707 Jacobian.v[1].n[j] = ((fxd[1] - fx[1]) / JACOBIAN_EPSILON);
1708 Jacobian.v[2].n[j] = ((fxd[2] - fx[2]) / JACOBIAN_EPSILON);
1712 tmp2.n[0] = fx[0] - Target[0];
1713 tmp2.n[1] = fx[1] - Target[1];
1714 tmp2.n[2] = fx[2] - Target[2];
1716 if (!_cmsMAT3solve(&tmp, &Jacobian, &tmp2))
1720 x[0] -= (cmsFloat32Number) tmp.n[0];
1721 x[1] -= (cmsFloat32Number) tmp.n[1];
1722 x[2] -= (cmsFloat32Number) tmp.n[2];
1724 // Some clipping....
1725 for (j=0; j < 3; j++) {
1726 if (x[j] < 0) x[j] = 0;
1728 if (x[j] > 1.0) x[j] = 1.0;