1 //---------------------------------------------------------------------------------
3 // Little Color Management System
4 // Copyright (c) 1998-2012 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);
294 // Create a bunch of identity curves
295 cmsStage* _cmsStageAllocIdentityCurves(cmsContext ContextID, int nChannels)
297 cmsStage* mpe = cmsStageAllocToneCurves(ContextID, nChannels, NULL);
299 if (mpe == NULL) return NULL;
300 mpe ->Implements = cmsSigIdentityElemType;
305 // *************************************************************************************************
306 // Type cmsSigMatrixElemType (Matrices)
307 // *************************************************************************************************
310 // Special care should be taken here because precision loss. A temporary cmsFloat64Number buffer is being used
312 void EvaluateMatrix(const cmsFloat32Number In[],
313 cmsFloat32Number Out[],
316 cmsUInt32Number i, j;
317 _cmsStageMatrixData* Data = (_cmsStageMatrixData*) mpe ->Data;
318 cmsFloat64Number Tmp;
320 // Input is already in 0..1.0 notation
321 for (i=0; i < mpe ->OutputChannels; i++) {
324 for (j=0; j < mpe->InputChannels; j++) {
325 Tmp += In[j] * Data->Double[i*mpe->InputChannels + j];
328 if (Data ->Offset != NULL)
329 Tmp += Data->Offset[i];
331 Out[i] = (cmsFloat32Number) Tmp;
335 // Output in 0..1.0 domain
339 // Duplicate a yet-existing matrix element
341 void* MatrixElemDup(cmsStage* mpe)
343 _cmsStageMatrixData* Data = (_cmsStageMatrixData*) mpe ->Data;
344 _cmsStageMatrixData* NewElem;
347 NewElem = (_cmsStageMatrixData*) _cmsMallocZero(mpe ->ContextID, sizeof(_cmsStageMatrixData));
348 if (NewElem == NULL) return NULL;
350 sz = mpe ->InputChannels * mpe ->OutputChannels;
352 NewElem ->Double = (cmsFloat64Number*) _cmsDupMem(mpe ->ContextID, Data ->Double, sz * sizeof(cmsFloat64Number)) ;
355 NewElem ->Offset = (cmsFloat64Number*) _cmsDupMem(mpe ->ContextID,
356 Data ->Offset, mpe -> OutputChannels * sizeof(cmsFloat64Number)) ;
358 return (void*) NewElem;
363 void MatrixElemTypeFree(cmsStage* mpe)
365 _cmsStageMatrixData* Data = (_cmsStageMatrixData*) mpe ->Data;
367 _cmsFree(mpe ->ContextID, Data ->Double);
370 _cmsFree(mpe ->ContextID, Data ->Offset);
372 _cmsFree(mpe ->ContextID, mpe ->Data);
377 cmsStage* CMSEXPORT cmsStageAllocMatrix(cmsContext ContextID, cmsUInt32Number Rows, cmsUInt32Number Cols,
378 const cmsFloat64Number* Matrix, const cmsFloat64Number* Offset)
380 cmsUInt32Number i, n;
381 _cmsStageMatrixData* NewElem;
386 // Check for overflow
387 if (n == 0) return NULL;
388 if (n >= UINT_MAX / Cols) return NULL;
389 if (n >= UINT_MAX / Rows) return NULL;
390 if (n < Rows || n < Cols) return NULL;
392 NewMPE = _cmsStageAllocPlaceholder(ContextID, cmsSigMatrixElemType, Cols, Rows,
393 EvaluateMatrix, MatrixElemDup, MatrixElemTypeFree, NULL );
394 if (NewMPE == NULL) return NULL;
397 NewElem = (_cmsStageMatrixData*) _cmsMallocZero(ContextID, sizeof(_cmsStageMatrixData));
398 if (NewElem == NULL) return NULL;
401 NewElem ->Double = (cmsFloat64Number*) _cmsCalloc(ContextID, n, sizeof(cmsFloat64Number));
403 if (NewElem->Double == NULL) {
404 MatrixElemTypeFree(NewMPE);
408 for (i=0; i < n; i++) {
409 NewElem ->Double[i] = Matrix[i];
413 if (Offset != NULL) {
415 NewElem ->Offset = (cmsFloat64Number*) _cmsCalloc(ContextID, Cols, sizeof(cmsFloat64Number));
416 if (NewElem->Offset == NULL) {
417 MatrixElemTypeFree(NewMPE);
421 for (i=0; i < Cols; i++) {
422 NewElem ->Offset[i] = Offset[i];
427 NewMPE ->Data = (void*) NewElem;
432 // *************************************************************************************************
433 // Type cmsSigCLutElemType
434 // *************************************************************************************************
437 // Evaluate in true floating point
439 void EvaluateCLUTfloat(const cmsFloat32Number In[], cmsFloat32Number Out[], const cmsStage *mpe)
441 _cmsStageCLutData* Data = (_cmsStageCLutData*) mpe ->Data;
443 Data -> Params ->Interpolation.LerpFloat(In, Out, Data->Params);
447 // Convert to 16 bits, evaluate, and back to floating point
449 void EvaluateCLUTfloatIn16(const cmsFloat32Number In[], cmsFloat32Number Out[], const cmsStage *mpe)
451 _cmsStageCLutData* Data = (_cmsStageCLutData*) mpe ->Data;
452 cmsUInt16Number In16[MAX_STAGE_CHANNELS], Out16[MAX_STAGE_CHANNELS];
454 _cmsAssert(mpe ->InputChannels <= MAX_STAGE_CHANNELS);
455 _cmsAssert(mpe ->OutputChannels <= MAX_STAGE_CHANNELS);
457 FromFloatTo16(In, In16, mpe ->InputChannels);
458 Data -> Params ->Interpolation.Lerp16(In16, Out16, Data->Params);
459 From16ToFloat(Out16, Out, mpe ->OutputChannels);
463 // Given an hypercube of b dimensions, with Dims[] number of nodes by dimension, calculate the total amount of nodes
465 cmsUInt32Number CubeSize(const cmsUInt32Number Dims[], cmsUInt32Number b)
467 cmsUInt32Number rv, dim;
469 _cmsAssert(Dims != NULL);
471 for (rv = 1; b > 0; b--) {
474 if (dim == 0) return 0; // Error
478 // Check for overflow
479 if (rv > UINT_MAX / dim) return 0;
486 void* CLUTElemDup(cmsStage* mpe)
488 _cmsStageCLutData* Data = (_cmsStageCLutData*) mpe ->Data;
489 _cmsStageCLutData* NewElem;
492 NewElem = (_cmsStageCLutData*) _cmsMallocZero(mpe ->ContextID, sizeof(_cmsStageCLutData));
493 if (NewElem == NULL) return NULL;
495 NewElem ->nEntries = Data ->nEntries;
496 NewElem ->HasFloatValues = Data ->HasFloatValues;
500 if (Data ->HasFloatValues)
501 NewElem ->Tab.TFloat = (cmsFloat32Number*) _cmsDupMem(mpe ->ContextID, Data ->Tab.TFloat, Data ->nEntries * sizeof (cmsFloat32Number));
503 NewElem ->Tab.T = (cmsUInt16Number*) _cmsDupMem(mpe ->ContextID, Data ->Tab.T, Data ->nEntries * sizeof (cmsUInt16Number));
506 NewElem ->Params = _cmsComputeInterpParamsEx(mpe ->ContextID,
507 Data ->Params ->nSamples,
508 Data ->Params ->nInputs,
509 Data ->Params ->nOutputs,
511 Data ->Params ->dwFlags);
513 return (void*) NewElem;
518 void CLutElemTypeFree(cmsStage* mpe)
521 _cmsStageCLutData* Data = (_cmsStageCLutData*) mpe ->Data;
524 if (Data == NULL) return;
526 // This works for both types
528 _cmsFree(mpe ->ContextID, Data -> Tab.T);
530 _cmsFreeInterpParams(Data ->Params);
531 _cmsFree(mpe ->ContextID, mpe ->Data);
535 // Allocates a 16-bit multidimensional CLUT. This is evaluated at 16-bit precision. Table may have different
536 // granularity on each dimension.
537 cmsStage* CMSEXPORT cmsStageAllocCLut16bitGranular(cmsContext ContextID,
538 const cmsUInt32Number clutPoints[],
539 cmsUInt32Number inputChan,
540 cmsUInt32Number outputChan,
541 const cmsUInt16Number* Table)
543 cmsUInt32Number i, n;
544 _cmsStageCLutData* NewElem;
547 _cmsAssert(clutPoints != NULL);
549 if (inputChan > MAX_INPUT_DIMENSIONS) {
550 cmsSignalError(ContextID, cmsERROR_RANGE, "Too many input channels (%d channels, max=%d)", inputChan, MAX_INPUT_DIMENSIONS);
554 NewMPE = _cmsStageAllocPlaceholder(ContextID, cmsSigCLutElemType, inputChan, outputChan,
555 EvaluateCLUTfloatIn16, CLUTElemDup, CLutElemTypeFree, NULL );
557 if (NewMPE == NULL) return NULL;
559 NewElem = (_cmsStageCLutData*) _cmsMallocZero(ContextID, sizeof(_cmsStageCLutData));
560 if (NewElem == NULL) {
561 cmsStageFree(NewMPE);
565 NewMPE ->Data = (void*) NewElem;
567 NewElem -> nEntries = n = outputChan * CubeSize(clutPoints, inputChan);
568 NewElem -> HasFloatValues = FALSE;
571 cmsStageFree(NewMPE);
576 NewElem ->Tab.T = (cmsUInt16Number*) _cmsCalloc(ContextID, n, sizeof(cmsUInt16Number));
577 if (NewElem ->Tab.T == NULL) {
578 cmsStageFree(NewMPE);
583 for (i=0; i < n; i++) {
584 NewElem ->Tab.T[i] = Table[i];
588 NewElem ->Params = _cmsComputeInterpParamsEx(ContextID, clutPoints, inputChan, outputChan, NewElem ->Tab.T, CMS_LERP_FLAGS_16BITS);
589 if (NewElem ->Params == NULL) {
590 cmsStageFree(NewMPE);
597 cmsStage* CMSEXPORT cmsStageAllocCLut16bit(cmsContext ContextID,
598 cmsUInt32Number nGridPoints,
599 cmsUInt32Number inputChan,
600 cmsUInt32Number outputChan,
601 const cmsUInt16Number* Table)
603 cmsUInt32Number Dimensions[MAX_INPUT_DIMENSIONS];
606 // Our resulting LUT would be same gridpoints on all dimensions
607 for (i=0; i < MAX_INPUT_DIMENSIONS; i++)
608 Dimensions[i] = nGridPoints;
611 return cmsStageAllocCLut16bitGranular(ContextID, Dimensions, inputChan, outputChan, Table);
615 cmsStage* CMSEXPORT cmsStageAllocCLutFloat(cmsContext ContextID,
616 cmsUInt32Number nGridPoints,
617 cmsUInt32Number inputChan,
618 cmsUInt32Number outputChan,
619 const cmsFloat32Number* Table)
621 cmsUInt32Number Dimensions[MAX_INPUT_DIMENSIONS];
624 // Our resulting LUT would be same gridpoints on all dimensions
625 for (i=0; i < MAX_INPUT_DIMENSIONS; i++)
626 Dimensions[i] = nGridPoints;
628 return cmsStageAllocCLutFloatGranular(ContextID, Dimensions, inputChan, outputChan, Table);
633 cmsStage* CMSEXPORT cmsStageAllocCLutFloatGranular(cmsContext ContextID, const cmsUInt32Number clutPoints[], cmsUInt32Number inputChan, cmsUInt32Number outputChan, const cmsFloat32Number* Table)
635 cmsUInt32Number i, n;
636 _cmsStageCLutData* NewElem;
639 _cmsAssert(clutPoints != NULL);
641 if (inputChan > MAX_INPUT_DIMENSIONS) {
642 cmsSignalError(ContextID, cmsERROR_RANGE, "Too many input channels (%d channels, max=%d)", inputChan, MAX_INPUT_DIMENSIONS);
646 NewMPE = _cmsStageAllocPlaceholder(ContextID, cmsSigCLutElemType, inputChan, outputChan,
647 EvaluateCLUTfloat, CLUTElemDup, CLutElemTypeFree, NULL);
648 if (NewMPE == NULL) return NULL;
651 NewElem = (_cmsStageCLutData*) _cmsMallocZero(ContextID, sizeof(_cmsStageCLutData));
652 if (NewElem == NULL) {
653 cmsStageFree(NewMPE);
657 NewMPE ->Data = (void*) NewElem;
659 // There is a potential integer overflow on conputing n and nEntries.
660 NewElem -> nEntries = n = outputChan * CubeSize(clutPoints, inputChan);
661 NewElem -> HasFloatValues = TRUE;
664 cmsStageFree(NewMPE);
668 NewElem ->Tab.TFloat = (cmsFloat32Number*) _cmsCalloc(ContextID, n, sizeof(cmsFloat32Number));
669 if (NewElem ->Tab.TFloat == NULL) {
670 cmsStageFree(NewMPE);
675 for (i=0; i < n; i++) {
676 NewElem ->Tab.TFloat[i] = Table[i];
681 NewElem ->Params = _cmsComputeInterpParamsEx(ContextID, clutPoints, inputChan, outputChan, NewElem ->Tab.TFloat, CMS_LERP_FLAGS_FLOAT);
682 if (NewElem ->Params == NULL) {
683 cmsStageFree(NewMPE);
694 int IdentitySampler(register const cmsUInt16Number In[], register cmsUInt16Number Out[], register void * Cargo)
696 int nChan = *(int*) Cargo;
699 for (i=0; i < nChan; i++)
705 // Creates an MPE that just copies input to output
706 cmsStage* _cmsStageAllocIdentityCLut(cmsContext ContextID, int nChan)
708 cmsUInt32Number Dimensions[MAX_INPUT_DIMENSIONS];
712 for (i=0; i < MAX_INPUT_DIMENSIONS; i++)
715 mpe = cmsStageAllocCLut16bitGranular(ContextID, Dimensions, nChan, nChan, NULL);
716 if (mpe == NULL) return NULL;
718 if (!cmsStageSampleCLut16bit(mpe, IdentitySampler, &nChan, 0)) {
723 mpe ->Implements = cmsSigIdentityElemType;
729 // Quantize a value 0 <= i < MaxSamples to 0..0xffff
730 cmsUInt16Number _cmsQuantizeVal(cmsFloat64Number i, int MaxSamples)
734 x = ((cmsFloat64Number) i * 65535.) / (cmsFloat64Number) (MaxSamples - 1);
735 return _cmsQuickSaturateWord(x);
739 // This routine does a sweep on whole input space, and calls its callback
740 // function on knots. returns TRUE if all ok, FALSE otherwise.
741 cmsBool CMSEXPORT cmsStageSampleCLut16bit(cmsStage* mpe, cmsSAMPLER16 Sampler, void * Cargo, cmsUInt32Number dwFlags)
743 int i, t, nTotalPoints, index, rest;
744 int nInputs, nOutputs;
745 cmsUInt32Number* nSamples;
746 cmsUInt16Number In[cmsMAXCHANNELS], Out[MAX_STAGE_CHANNELS];
747 _cmsStageCLutData* clut;
749 if (mpe == NULL) return FALSE;
751 clut = (_cmsStageCLutData*) mpe->Data;
753 if (clut == NULL) return FALSE;
755 nSamples = clut->Params ->nSamples;
756 nInputs = clut->Params ->nInputs;
757 nOutputs = clut->Params ->nOutputs;
759 if (nInputs >= cmsMAXCHANNELS) return FALSE;
760 if (nOutputs >= MAX_STAGE_CHANNELS) return FALSE;
762 nTotalPoints = CubeSize(nSamples, nInputs);
763 if (nTotalPoints == 0) return FALSE;
766 for (i = 0; i < nTotalPoints; i++) {
769 for (t = nInputs-1; t >=0; --t) {
771 cmsUInt32Number Colorant = rest % nSamples[t];
775 In[t] = _cmsQuantizeVal(Colorant, nSamples[t]);
778 if (clut ->Tab.T != NULL) {
779 for (t=0; t < nOutputs; t++)
780 Out[t] = clut->Tab.T[index + t];
783 if (!Sampler(In, Out, Cargo))
786 if (!(dwFlags & SAMPLER_INSPECT)) {
788 if (clut ->Tab.T != NULL) {
789 for (t=0; t < nOutputs; t++)
790 clut->Tab.T[index + t] = Out[t];
800 // Same as anterior, but for floting point
801 cmsBool CMSEXPORT cmsStageSampleCLutFloat(cmsStage* mpe, cmsSAMPLERFLOAT Sampler, void * Cargo, cmsUInt32Number dwFlags)
803 int i, t, nTotalPoints, index, rest;
804 int nInputs, nOutputs;
805 cmsUInt32Number* nSamples;
806 cmsFloat32Number In[cmsMAXCHANNELS], Out[MAX_STAGE_CHANNELS];
807 _cmsStageCLutData* clut = (_cmsStageCLutData*) mpe->Data;
809 nSamples = clut->Params ->nSamples;
810 nInputs = clut->Params ->nInputs;
811 nOutputs = clut->Params ->nOutputs;
813 if (nInputs >= cmsMAXCHANNELS) return FALSE;
814 if (nOutputs >= MAX_STAGE_CHANNELS) return FALSE;
816 nTotalPoints = CubeSize(nSamples, nInputs);
817 if (nTotalPoints == 0) return FALSE;
820 for (i = 0; i < nTotalPoints; i++) {
823 for (t = nInputs-1; t >=0; --t) {
825 cmsUInt32Number Colorant = rest % nSamples[t];
829 In[t] = (cmsFloat32Number) (_cmsQuantizeVal(Colorant, nSamples[t]) / 65535.0);
832 if (clut ->Tab.TFloat != NULL) {
833 for (t=0; t < nOutputs; t++)
834 Out[t] = clut->Tab.TFloat[index + t];
837 if (!Sampler(In, Out, Cargo))
840 if (!(dwFlags & SAMPLER_INSPECT)) {
842 if (clut ->Tab.TFloat != NULL) {
843 for (t=0; t < nOutputs; t++)
844 clut->Tab.TFloat[index + t] = Out[t];
856 // This routine does a sweep on whole input space, and calls its callback
857 // function on knots. returns TRUE if all ok, FALSE otherwise.
858 cmsBool CMSEXPORT cmsSliceSpace16(cmsUInt32Number nInputs, const cmsUInt32Number clutPoints[],
859 cmsSAMPLER16 Sampler, void * Cargo)
861 int i, t, nTotalPoints, rest;
862 cmsUInt16Number In[cmsMAXCHANNELS];
864 if (nInputs >= cmsMAXCHANNELS) return FALSE;
866 nTotalPoints = CubeSize(clutPoints, nInputs);
867 if (nTotalPoints == 0) return FALSE;
869 for (i = 0; i < nTotalPoints; i++) {
872 for (t = nInputs-1; t >=0; --t) {
874 cmsUInt32Number Colorant = rest % clutPoints[t];
876 rest /= clutPoints[t];
877 In[t] = _cmsQuantizeVal(Colorant, clutPoints[t]);
881 if (!Sampler(In, NULL, Cargo))
888 cmsInt32Number CMSEXPORT cmsSliceSpaceFloat(cmsUInt32Number nInputs, const cmsUInt32Number clutPoints[],
889 cmsSAMPLERFLOAT Sampler, void * Cargo)
891 int i, t, nTotalPoints, rest;
892 cmsFloat32Number In[cmsMAXCHANNELS];
894 if (nInputs >= cmsMAXCHANNELS) return FALSE;
896 nTotalPoints = CubeSize(clutPoints, nInputs);
897 if (nTotalPoints == 0) return FALSE;
899 for (i = 0; i < nTotalPoints; i++) {
902 for (t = nInputs-1; t >=0; --t) {
904 cmsUInt32Number Colorant = rest % clutPoints[t];
906 rest /= clutPoints[t];
907 In[t] = (cmsFloat32Number) (_cmsQuantizeVal(Colorant, clutPoints[t]) / 65535.0);
911 if (!Sampler(In, NULL, Cargo))
918 // ********************************************************************************
919 // Type cmsSigLab2XYZElemType
920 // ********************************************************************************
924 void EvaluateLab2XYZ(const cmsFloat32Number In[],
925 cmsFloat32Number Out[],
930 const cmsFloat64Number XYZadj = MAX_ENCODEABLE_XYZ;
933 Lab.L = In[0] * 100.0;
934 Lab.a = In[1] * 255.0 - 128.0;
935 Lab.b = In[2] * 255.0 - 128.0;
937 cmsLab2XYZ(NULL, &XYZ, &Lab);
939 // From XYZ, range 0..19997 to 0..1.0, note that 1.99997 comes from 0xffff
940 // encoded as 1.15 fixed point, so 1 + (32767.0 / 32768.0)
942 Out[0] = (cmsFloat32Number) ((cmsFloat64Number) XYZ.X / XYZadj);
943 Out[1] = (cmsFloat32Number) ((cmsFloat64Number) XYZ.Y / XYZadj);
944 Out[2] = (cmsFloat32Number) ((cmsFloat64Number) XYZ.Z / XYZadj);
947 cmsUNUSED_PARAMETER(mpe);
951 // No dup or free routines needed, as the structure has no pointers in it.
952 cmsStage* _cmsStageAllocLab2XYZ(cmsContext ContextID)
954 return _cmsStageAllocPlaceholder(ContextID, cmsSigLab2XYZElemType, 3, 3, EvaluateLab2XYZ, NULL, NULL, NULL);
957 // ********************************************************************************
959 // v2 L=100 is supposed to be placed on 0xFF00. There is no reasonable
960 // number of gridpoints that would make exact match. However, a prelinearization
961 // of 258 entries, would map 0xFF00 exactly on entry 257, and this is good to avoid scum dot.
962 // Almost all what we need but unfortunately, the rest of entries should be scaled by
963 // (255*257/256) and this is not exact.
965 cmsStage* _cmsStageAllocLabV2ToV4curves(cmsContext ContextID)
968 cmsToneCurve* LabTable[3];
971 LabTable[0] = cmsBuildTabulatedToneCurve16(ContextID, 258, NULL);
972 LabTable[1] = cmsBuildTabulatedToneCurve16(ContextID, 258, NULL);
973 LabTable[2] = cmsBuildTabulatedToneCurve16(ContextID, 258, NULL);
975 for (j=0; j < 3; j++) {
977 if (LabTable[j] == NULL) {
978 cmsFreeToneCurveTriple(LabTable);
982 // We need to map * (0xffff / 0xff00), thats same as (257 / 256)
983 // So we can use 258-entry tables to do the trick (i / 257) * (255 * 257) * (257 / 256);
984 for (i=0; i < 257; i++) {
986 LabTable[j]->Table16[i] = (cmsUInt16Number) ((i * 0xffff + 0x80) >> 8);
989 LabTable[j] ->Table16[257] = 0xffff;
992 mpe = cmsStageAllocToneCurves(ContextID, 3, LabTable);
993 cmsFreeToneCurveTriple(LabTable);
995 mpe ->Implements = cmsSigLabV2toV4;
999 // ********************************************************************************
1001 // Matrix-based conversion, which is more accurate, but slower and cannot properly be saved in devicelink profiles
1002 cmsStage* _cmsStageAllocLabV2ToV4(cmsContext ContextID)
1004 static const cmsFloat64Number V2ToV4[] = { 65535.0/65280.0, 0, 0,
1005 0, 65535.0/65280.0, 0,
1006 0, 0, 65535.0/65280.0
1009 cmsStage *mpe = cmsStageAllocMatrix(ContextID, 3, 3, V2ToV4, NULL);
1011 if (mpe == NULL) return mpe;
1012 mpe ->Implements = cmsSigLabV2toV4;
1017 // Reverse direction
1018 cmsStage* _cmsStageAllocLabV4ToV2(cmsContext ContextID)
1020 static const cmsFloat64Number V4ToV2[] = { 65280.0/65535.0, 0, 0,
1021 0, 65280.0/65535.0, 0,
1022 0, 0, 65280.0/65535.0
1025 cmsStage *mpe = cmsStageAllocMatrix(ContextID, 3, 3, V4ToV2, NULL);
1027 if (mpe == NULL) return mpe;
1028 mpe ->Implements = cmsSigLabV4toV2;
1033 // To Lab to float. Note that the MPE gives numbers in normal Lab range
1034 // and we need 0..1.0 range for the formatters
1035 // L* : 0...100 => 0...1.0 (L* / 100)
1036 // ab* : -128..+127 to 0..1 ((ab* + 128) / 255)
1038 cmsStage* _cmsStageNormalizeFromLabFloat(cmsContext ContextID)
1040 static const cmsFloat64Number a1[] = {
1046 static const cmsFloat64Number o1[] = {
1052 cmsStage *mpe = cmsStageAllocMatrix(ContextID, 3, 3, a1, o1);
1054 if (mpe == NULL) return mpe;
1055 mpe ->Implements = cmsSigLab2FloatPCS;
1059 // Fom XYZ to floating point PCS
1060 cmsStage* _cmsStageNormalizeFromXyzFloat(cmsContext ContextID)
1062 #define n (32768.0/65535.0)
1063 static const cmsFloat64Number a1[] = {
1070 cmsStage *mpe = cmsStageAllocMatrix(ContextID, 3, 3, a1, NULL);
1072 if (mpe == NULL) return mpe;
1073 mpe ->Implements = cmsSigXYZ2FloatPCS;
1077 cmsStage* _cmsStageNormalizeToLabFloat(cmsContext ContextID)
1079 static const cmsFloat64Number a1[] = {
1085 static const cmsFloat64Number o1[] = {
1091 cmsStage *mpe = cmsStageAllocMatrix(ContextID, 3, 3, a1, o1);
1092 if (mpe == NULL) return mpe;
1093 mpe ->Implements = cmsSigFloatPCS2Lab;
1097 cmsStage* _cmsStageNormalizeToXyzFloat(cmsContext ContextID)
1099 #define n (65535.0/32768.0)
1101 static const cmsFloat64Number a1[] = {
1108 cmsStage *mpe = cmsStageAllocMatrix(ContextID, 3, 3, a1, NULL);
1109 if (mpe == NULL) return mpe;
1110 mpe ->Implements = cmsSigFloatPCS2XYZ;
1116 // ********************************************************************************
1117 // Type cmsSigXYZ2LabElemType
1118 // ********************************************************************************
1121 void EvaluateXYZ2Lab(const cmsFloat32Number In[], cmsFloat32Number Out[], const cmsStage *mpe)
1125 const cmsFloat64Number XYZadj = MAX_ENCODEABLE_XYZ;
1127 // From 0..1.0 to XYZ
1129 XYZ.X = In[0] * XYZadj;
1130 XYZ.Y = In[1] * XYZadj;
1131 XYZ.Z = In[2] * XYZadj;
1133 cmsXYZ2Lab(NULL, &Lab, &XYZ);
1135 // From V4 Lab to 0..1.0
1137 Out[0] = (cmsFloat32Number) (Lab.L / 100.0);
1138 Out[1] = (cmsFloat32Number) ((Lab.a + 128.0) / 255.0);
1139 Out[2] = (cmsFloat32Number) ((Lab.b + 128.0) / 255.0);
1142 cmsUNUSED_PARAMETER(mpe);
1145 cmsStage* _cmsStageAllocXYZ2Lab(cmsContext ContextID)
1147 return _cmsStageAllocPlaceholder(ContextID, cmsSigXYZ2LabElemType, 3, 3, EvaluateXYZ2Lab, NULL, NULL, NULL);
1151 // ********************************************************************************
1153 // For v4, S-Shaped curves are placed in a/b axis to increase resolution near gray
1155 cmsStage* _cmsStageAllocLabPrelin(cmsContext ContextID)
1157 cmsToneCurve* LabTable[3];
1158 cmsFloat64Number Params[1] = {2.4} ;
1160 LabTable[0] = cmsBuildGamma(ContextID, 1.0);
1161 LabTable[1] = cmsBuildParametricToneCurve(ContextID, 108, Params);
1162 LabTable[2] = cmsBuildParametricToneCurve(ContextID, 108, Params);
1164 return cmsStageAllocToneCurves(ContextID, 3, LabTable);
1168 // Free a single MPE
1169 void CMSEXPORT cmsStageFree(cmsStage* mpe)
1174 _cmsFree(mpe ->ContextID, mpe);
1178 cmsUInt32Number CMSEXPORT cmsStageInputChannels(const cmsStage* mpe)
1180 return mpe ->InputChannels;
1183 cmsUInt32Number CMSEXPORT cmsStageOutputChannels(const cmsStage* mpe)
1185 return mpe ->OutputChannels;
1188 cmsStageSignature CMSEXPORT cmsStageType(const cmsStage* mpe)
1193 void* CMSEXPORT cmsStageData(const cmsStage* mpe)
1198 cmsStage* CMSEXPORT cmsStageNext(const cmsStage* mpe)
1204 // Duplicates an MPE
1205 cmsStage* CMSEXPORT cmsStageDup(cmsStage* mpe)
1209 if (mpe == NULL) return NULL;
1210 NewMPE = _cmsStageAllocPlaceholder(mpe ->ContextID,
1212 mpe ->InputChannels,
1213 mpe ->OutputChannels,
1218 if (NewMPE == NULL) return NULL;
1220 NewMPE ->Implements = mpe ->Implements;
1222 if (mpe ->DupElemPtr)
1223 NewMPE ->Data = mpe ->DupElemPtr(mpe);
1225 NewMPE ->Data = NULL;
1231 // ***********************************************************************************************************
1233 // This function sets up the channel count
1236 void BlessLUT(cmsPipeline* lut)
1238 // We can set the input/ouput channels only if we have elements.
1239 if (lut ->Elements != NULL) {
1241 cmsStage *First, *Last;
1243 First = cmsPipelineGetPtrToFirstStage(lut);
1244 Last = cmsPipelineGetPtrToLastStage(lut);
1246 if (First != NULL)lut ->InputChannels = First ->InputChannels;
1247 if (Last != NULL) lut ->OutputChannels = Last ->OutputChannels;
1252 // Default to evaluate the LUT on 16 bit-basis. Precision is retained.
1254 void _LUTeval16(register const cmsUInt16Number In[], register cmsUInt16Number Out[], register const void* D)
1256 cmsPipeline* lut = (cmsPipeline*) D;
1258 cmsFloat32Number Storage[2][MAX_STAGE_CHANNELS];
1259 int Phase = 0, NextPhase;
1261 From16ToFloat(In, &Storage[Phase][0], lut ->InputChannels);
1263 for (mpe = lut ->Elements;
1267 NextPhase = Phase ^ 1;
1268 mpe ->EvalPtr(&Storage[Phase][0], &Storage[NextPhase][0], mpe);
1273 FromFloatTo16(&Storage[Phase][0], Out, lut ->OutputChannels);
1278 // Does evaluate the LUT on cmsFloat32Number-basis.
1280 void _LUTevalFloat(register const cmsFloat32Number In[], register cmsFloat32Number Out[], const void* D)
1282 cmsPipeline* lut = (cmsPipeline*) D;
1284 cmsFloat32Number Storage[2][MAX_STAGE_CHANNELS];
1285 int Phase = 0, NextPhase;
1287 memmove(&Storage[Phase][0], In, lut ->InputChannels * sizeof(cmsFloat32Number));
1289 for (mpe = lut ->Elements;
1293 NextPhase = Phase ^ 1;
1294 mpe ->EvalPtr(&Storage[Phase][0], &Storage[NextPhase][0], mpe);
1298 memmove(Out, &Storage[Phase][0], lut ->OutputChannels * sizeof(cmsFloat32Number));
1304 // LUT Creation & Destruction
1306 cmsPipeline* CMSEXPORT cmsPipelineAlloc(cmsContext ContextID, cmsUInt32Number InputChannels, cmsUInt32Number OutputChannels)
1308 cmsPipeline* NewLUT;
1310 if (InputChannels >= cmsMAXCHANNELS ||
1311 OutputChannels >= cmsMAXCHANNELS) return NULL;
1313 NewLUT = (cmsPipeline*) _cmsMallocZero(ContextID, sizeof(cmsPipeline));
1314 if (NewLUT == NULL) return NULL;
1317 NewLUT -> InputChannels = InputChannels;
1318 NewLUT -> OutputChannels = OutputChannels;
1320 NewLUT ->Eval16Fn = _LUTeval16;
1321 NewLUT ->EvalFloatFn = _LUTevalFloat;
1322 NewLUT ->DupDataFn = NULL;
1323 NewLUT ->FreeDataFn = NULL;
1324 NewLUT ->Data = NewLUT;
1325 NewLUT ->ContextID = ContextID;
1332 cmsContext CMSEXPORT cmsGetPipelineContextID(const cmsPipeline* lut)
1334 _cmsAssert(lut != NULL);
1335 return lut ->ContextID;
1338 cmsUInt32Number CMSEXPORT cmsPipelineInputChannels(const cmsPipeline* lut)
1340 _cmsAssert(lut != NULL);
1341 return lut ->InputChannels;
1344 cmsUInt32Number CMSEXPORT cmsPipelineOutputChannels(const cmsPipeline* lut)
1346 _cmsAssert(lut != NULL);
1347 return lut ->OutputChannels;
1350 // Free a profile elements LUT
1351 void CMSEXPORT cmsPipelineFree(cmsPipeline* lut)
1353 cmsStage *mpe, *Next;
1355 if (lut == NULL) return;
1357 for (mpe = lut ->Elements;
1365 if (lut ->FreeDataFn) lut ->FreeDataFn(lut ->ContextID, lut ->Data);
1367 _cmsFree(lut ->ContextID, lut);
1371 // Default to evaluate the LUT on 16 bit-basis.
1372 void CMSEXPORT cmsPipelineEval16(const cmsUInt16Number In[], cmsUInt16Number Out[], const cmsPipeline* lut)
1374 _cmsAssert(lut != NULL);
1375 lut ->Eval16Fn(In, Out, lut->Data);
1379 // Does evaluate the LUT on cmsFloat32Number-basis.
1380 void CMSEXPORT cmsPipelineEvalFloat(const cmsFloat32Number In[], cmsFloat32Number Out[], const cmsPipeline* lut)
1382 _cmsAssert(lut != NULL);
1383 lut ->EvalFloatFn(In, Out, lut);
1389 cmsPipeline* CMSEXPORT cmsPipelineDup(const cmsPipeline* lut)
1391 cmsPipeline* NewLUT;
1392 cmsStage *NewMPE, *Anterior = NULL, *mpe;
1393 cmsBool First = TRUE;
1395 if (lut == NULL) return NULL;
1397 NewLUT = cmsPipelineAlloc(lut ->ContextID, lut ->InputChannels, lut ->OutputChannels);
1398 for (mpe = lut ->Elements;
1402 NewMPE = cmsStageDup(mpe);
1404 if (NewMPE == NULL) {
1405 cmsPipelineFree(NewLUT);
1410 NewLUT ->Elements = NewMPE;
1414 Anterior ->Next = NewMPE;
1420 NewLUT ->Eval16Fn = lut ->Eval16Fn;
1421 NewLUT ->EvalFloatFn = lut ->EvalFloatFn;
1422 NewLUT ->DupDataFn = lut ->DupDataFn;
1423 NewLUT ->FreeDataFn = lut ->FreeDataFn;
1425 if (NewLUT ->DupDataFn != NULL)
1426 NewLUT ->Data = NewLUT ->DupDataFn(lut ->ContextID, lut->Data);
1429 NewLUT ->SaveAs8Bits = lut ->SaveAs8Bits;
1436 void CMSEXPORT cmsPipelineInsertStage(cmsPipeline* lut, cmsStageLoc loc, cmsStage* mpe)
1438 cmsStage* Anterior = NULL, *pt;
1440 _cmsAssert(lut != NULL);
1441 _cmsAssert(mpe != NULL);
1446 mpe ->Next = lut ->Elements;
1447 lut ->Elements = mpe;
1452 if (lut ->Elements == NULL)
1453 lut ->Elements = mpe;
1456 for (pt = lut ->Elements;
1458 pt = pt -> Next) Anterior = pt;
1460 Anterior ->Next = mpe;
1470 // Unlink an element and return the pointer to it
1471 void CMSEXPORT cmsPipelineUnlinkStage(cmsPipeline* lut, cmsStageLoc loc, cmsStage** mpe)
1473 cmsStage *Anterior, *pt, *Last;
1474 cmsStage *Unlinked = NULL;
1477 // If empty LUT, there is nothing to remove
1478 if (lut ->Elements == NULL) {
1479 if (mpe) *mpe = NULL;
1483 // On depending on the strategy...
1488 cmsStage* elem = lut ->Elements;
1490 lut ->Elements = elem -> Next;
1498 Anterior = Last = NULL;
1499 for (pt = lut ->Elements;
1506 Unlinked = Last; // Next already points to NULL
1508 // Truncate the chain
1510 Anterior ->Next = NULL;
1512 lut ->Elements = NULL;
1520 cmsStageFree(Unlinked);
1526 // Concatenate two LUT into a new single one
1527 cmsBool CMSEXPORT cmsPipelineCat(cmsPipeline* l1, const cmsPipeline* l2)
1529 cmsStage* mpe, *NewMPE;
1531 // If both LUTS does not have elements, we need to inherit
1532 // the number of channels
1533 if (l1 ->Elements == NULL && l2 ->Elements == NULL) {
1534 l1 ->InputChannels = l2 ->InputChannels;
1535 l1 ->OutputChannels = l2 ->OutputChannels;
1539 for (mpe = l2 ->Elements;
1543 // We have to dup each element
1544 NewMPE = cmsStageDup(mpe);
1546 if (NewMPE == NULL) {
1550 cmsPipelineInsertStage(l1, cmsAT_END, NewMPE);
1558 cmsBool CMSEXPORT cmsPipelineSetSaveAs8bitsFlag(cmsPipeline* lut, cmsBool On)
1560 cmsBool Anterior = lut ->SaveAs8Bits;
1562 lut ->SaveAs8Bits = On;
1567 cmsStage* CMSEXPORT cmsPipelineGetPtrToFirstStage(const cmsPipeline* lut)
1569 return lut ->Elements;
1572 cmsStage* CMSEXPORT cmsPipelineGetPtrToLastStage(const cmsPipeline* lut)
1574 cmsStage *mpe, *Anterior = NULL;
1576 for (mpe = lut ->Elements; mpe != NULL; mpe = mpe ->Next)
1582 cmsUInt32Number CMSEXPORT cmsPipelineStageCount(const cmsPipeline* lut)
1587 for (n=0, mpe = lut ->Elements; mpe != NULL; mpe = mpe ->Next)
1593 // This function may be used to set the optional evaluator and a block of private data. If private data is being used, an optional
1594 // duplicator and free functions should also be specified in order to duplicate the LUT construct. Use NULL to inhibit such functionality.
1595 void CMSEXPORT _cmsPipelineSetOptimizationParameters(cmsPipeline* Lut,
1596 _cmsOPTeval16Fn Eval16,
1598 _cmsFreeUserDataFn FreePrivateDataFn,
1599 _cmsDupUserDataFn DupPrivateDataFn)
1602 Lut ->Eval16Fn = Eval16;
1603 Lut ->DupDataFn = DupPrivateDataFn;
1604 Lut ->FreeDataFn = FreePrivateDataFn;
1605 Lut ->Data = PrivateData;
1609 // ----------------------------------------------------------- Reverse interpolation
1610 // Here's how it goes. The derivative Df(x) of the function f is the linear
1611 // transformation that best approximates f near the point x. It can be represented
1612 // by a matrix A whose entries are the partial derivatives of the components of f
1613 // with respect to all the coordinates. This is know as the Jacobian
1615 // The best linear approximation to f is given by the matrix equation:
1619 // So, if x0 is a good "guess" for the zero of f, then solving for the zero of this
1620 // linear approximation will give a "better guess" for the zero of f. Thus let y=0,
1621 // and since y0=f(x0) one can solve the above equation for x. This leads to the
1622 // Newton's method formula:
1624 // xn+1 = xn - A-1 f(xn)
1626 // where xn+1 denotes the (n+1)-st guess, obtained from the n-th guess xn in the
1627 // fashion described above. Iterating this will give better and better approximations
1628 // if you have a "good enough" initial guess.
1631 #define JACOBIAN_EPSILON 0.001f
1632 #define INVERSION_MAX_ITERATIONS 30
1634 // Increment with reflexion on boundary
1636 void IncDelta(cmsFloat32Number *Val)
1638 if (*Val < (1.0 - JACOBIAN_EPSILON))
1640 *Val += JACOBIAN_EPSILON;
1643 *Val -= JACOBIAN_EPSILON;
1649 // Euclidean distance between two vectors of n elements each one
1651 cmsFloat32Number EuclideanDistance(cmsFloat32Number a[], cmsFloat32Number b[], int n)
1653 cmsFloat32Number sum = 0;
1656 for (i=0; i < n; i++) {
1657 cmsFloat32Number dif = b[i] - a[i];
1665 // Evaluate a LUT in reverse direction. It only searches on 3->3 LUT. Uses Newton method
1667 // x1 <- x - [J(x)]^-1 * f(x)
1669 // lut: The LUT on where to do the search
1670 // Target: LabK, 3 values of Lab plus destination K which is fixed
1671 // Result: The obtained CMYK
1672 // Hint: Location where begin the search
1674 cmsBool CMSEXPORT cmsPipelineEvalReverseFloat(cmsFloat32Number Target[],
1675 cmsFloat32Number Result[],
1676 cmsFloat32Number Hint[],
1677 const cmsPipeline* lut)
1679 cmsUInt32Number i, j;
1680 cmsFloat64Number error, LastError = 1E20;
1681 cmsFloat32Number fx[4], x[4], xd[4], fxd[4];
1684 cmsFloat64Number LastResult[4];
1687 // Only 3->3 and 4->3 are supported
1688 if (lut ->InputChannels != 3 && lut ->InputChannels != 4) return FALSE;
1689 if (lut ->OutputChannels != 3) return FALSE;
1691 // Mark result of -1
1692 LastResult[0] = LastResult[1] = LastResult[2] = -1.0f;
1694 // Take the hint as starting point if specified
1697 // Begin at any point, we choose 1/3 of CMY axis
1698 x[0] = x[1] = x[2] = 0.3f;
1702 // Only copy 3 channels from hint...
1703 for (j=0; j < 3; j++)
1707 // If Lut is 4-dimensions, then grab target[3], which is fixed
1708 if (lut ->InputChannels == 4) {
1711 else x[3] = 0; // To keep lint happy
1715 for (i = 0; i < INVERSION_MAX_ITERATIONS; i++) {
1718 cmsPipelineEvalFloat(x, fx, lut);
1721 error = EuclideanDistance(fx, Target, 3);
1723 // If not convergent, return last safe value
1724 if (error >= LastError)
1727 // Keep latest values
1729 for (j=0; j < lut ->InputChannels; j++)
1732 // Found an exact match?
1736 // Obtain slope (the Jacobian)
1737 for (j = 0; j < 3; j++) {
1742 xd[3] = x[3]; // Keep fixed channel
1746 cmsPipelineEvalFloat(xd, fxd, lut);
1748 Jacobian.v[0].n[j] = ((fxd[0] - fx[0]) / JACOBIAN_EPSILON);
1749 Jacobian.v[1].n[j] = ((fxd[1] - fx[1]) / JACOBIAN_EPSILON);
1750 Jacobian.v[2].n[j] = ((fxd[2] - fx[2]) / JACOBIAN_EPSILON);
1754 tmp2.n[0] = fx[0] - Target[0];
1755 tmp2.n[1] = fx[1] - Target[1];
1756 tmp2.n[2] = fx[2] - Target[2];
1758 if (!_cmsMAT3solve(&tmp, &Jacobian, &tmp2))
1762 x[0] -= (cmsFloat32Number) tmp.n[0];
1763 x[1] -= (cmsFloat32Number) tmp.n[1];
1764 x[2] -= (cmsFloat32Number) tmp.n[2];
1766 // Some clipping....
1767 for (j=0; j < 3; j++) {
1768 if (x[j] < 0) x[j] = 0;
1770 if (x[j] > 1.0) x[j] = 1.0;