openjpeg/thirdparty/liblcms2/src/cmslut.c

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//---------------------------------------------------------------------------------
//
// Little Color Management System
// Copyright (c) 1998-2010 Marti Maria Saguer
//
// Permission is hereby granted, free of charge, to any person obtaining
// a copy of this software and associated documentation files (the "Software"),
// to deal in the Software without restriction, including without limitation
// the rights to use, copy, modify, merge, publish, distribute, sublicense,
// and/or sell copies of the Software, and to permit persons to whom the Software
// is furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO
// THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//
//---------------------------------------------------------------------------------
//
#include "lcms2_internal.h"
// Allocates an empty multi profile element
cmsStage* CMSEXPORT _cmsStageAllocPlaceholder(cmsContext ContextID,
cmsStageSignature Type,
cmsUInt32Number InputChannels,
cmsUInt32Number OutputChannels,
_cmsStageEvalFn EvalPtr,
_cmsStageDupElemFn DupElemPtr,
_cmsStageFreeElemFn FreePtr,
void* Data)
{
cmsStage* ph = (cmsStage*) _cmsMallocZero(ContextID, sizeof(cmsStage));
if (ph == NULL) return NULL;
ph ->ContextID = ContextID;
ph ->Type = Type;
ph ->Implements = Type; // By default, no clue on what is implementing
ph ->InputChannels = InputChannels;
ph ->OutputChannels = OutputChannels;
ph ->EvalPtr = EvalPtr;
ph ->DupElemPtr = DupElemPtr;
ph ->FreePtr = FreePtr;
ph ->Data = Data;
return ph;
}
static
void EvaluateIdentity(const cmsFloat32Number In[],
cmsFloat32Number Out[],
const cmsStage *mpe)
{
memmove(Out, In, mpe ->InputChannels * sizeof(cmsFloat32Number));
}
cmsStage* CMSEXPORT cmsStageAllocIdentity(cmsContext ContextID, cmsUInt32Number nChannels)
{
return _cmsStageAllocPlaceholder(ContextID,
cmsSigIdentityElemType,
nChannels, nChannels,
EvaluateIdentity,
NULL,
NULL,
NULL);
}
// Conversion functions. From floating point to 16 bits
static
void FromFloatTo16(const cmsFloat32Number In[], cmsUInt16Number Out[], cmsUInt32Number n)
{
cmsUInt32Number i;
for (i=0; i < n; i++) {
Out[i] = _cmsQuickSaturateWord(In[i] * 65535.0);
}
}
// From 16 bits to floating point
static
void From16ToFloat(const cmsUInt16Number In[], cmsFloat32Number Out[], cmsUInt32Number n)
{
cmsUInt32Number i;
for (i=0; i < n; i++) {
Out[i] = (cmsFloat32Number) In[i] / 65535.0F;
}
}
// This function is quite useful to analyze the structure of a LUT and retrieve the MPE elements
// that conform the LUT. It should be called with the LUT, the number of expected elements and
// then a list of expected types followed with a list of cmsFloat64Number pointers to MPE elements. If
// the function founds a match with current pipeline, it fills the pointers and returns TRUE
// if not, returns FALSE without touching anything. Setting pointers to NULL does bypass
// the storage process.
cmsBool CMSEXPORT cmsPipelineCheckAndRetreiveStages(const cmsPipeline* Lut, cmsUInt32Number n, ...)
{
va_list args;
cmsUInt32Number i;
cmsStage* mpe;
cmsStageSignature Type;
void** ElemPtr;
// Make sure same number of elements
if (cmsPipelineStageCount(Lut) != n) return FALSE;
va_start(args, n);
// Iterate across asked types
mpe = Lut ->Elements;
for (i=0; i < n; i++) {
// Get asked type
Type = va_arg(args, cmsStageSignature);
if (mpe ->Type != Type) {
va_end(args); // Mismatch. We are done.
return FALSE;
}
mpe = mpe ->Next;
}
// Found a combination, fill pointers if not NULL
mpe = Lut ->Elements;
for (i=0; i < n; i++) {
ElemPtr = va_arg(args, void**);
if (ElemPtr != NULL)
*ElemPtr = mpe;
mpe = mpe ->Next;
}
va_end(args);
return TRUE;
}
// Below there are implementations for several types of elements. Each type may be implemented by a
// evaluation function, a duplication function, a function to free resources and a constructor.
// *************************************************************************************************
// Type cmsSigCurveSetElemType (curves)
// *************************************************************************************************
cmsToneCurve** _cmsStageGetPtrToCurveSet(const cmsStage* mpe)
{
_cmsStageToneCurvesData* Data = (_cmsStageToneCurvesData*) mpe ->Data;
return Data ->TheCurves;
}
static
void EvaluateCurves(const cmsFloat32Number In[],
cmsFloat32Number Out[],
const cmsStage *mpe)
{
_cmsStageToneCurvesData* Data;
cmsUInt32Number i;
_cmsAssert(mpe != NULL);
Data = (_cmsStageToneCurvesData*) mpe ->Data;
if (Data == NULL) return;
if (Data ->TheCurves == NULL) return;
for (i=0; i < Data ->nCurves; i++) {
Out[i] = cmsEvalToneCurveFloat(Data ->TheCurves[i], In[i]);
}
}
static
void CurveSetElemTypeFree(cmsStage* mpe)
{
_cmsStageToneCurvesData* Data;
cmsUInt32Number i;
_cmsAssert(mpe != NULL);
Data = (_cmsStageToneCurvesData*) mpe ->Data;
if (Data == NULL) return;
if (Data ->TheCurves != NULL) {
for (i=0; i < Data ->nCurves; i++) {
if (Data ->TheCurves[i] != NULL)
cmsFreeToneCurve(Data ->TheCurves[i]);
}
}
_cmsFree(mpe ->ContextID, Data ->TheCurves);
_cmsFree(mpe ->ContextID, Data);
}
static
void* CurveSetDup(cmsStage* mpe)
{
_cmsStageToneCurvesData* Data = (_cmsStageToneCurvesData*) mpe ->Data;
_cmsStageToneCurvesData* NewElem;
cmsUInt32Number i;
NewElem = (_cmsStageToneCurvesData*) _cmsMallocZero(mpe ->ContextID, sizeof(_cmsStageToneCurvesData));
if (NewElem == NULL) return NULL;
NewElem ->nCurves = Data ->nCurves;
NewElem ->TheCurves = (cmsToneCurve**) _cmsCalloc(mpe ->ContextID, NewElem ->nCurves, sizeof(cmsToneCurve*));
if (NewElem ->TheCurves == NULL) goto Error;
for (i=0; i < NewElem ->nCurves; i++) {
// Duplicate each curve. It may fail.
NewElem ->TheCurves[i] = cmsDupToneCurve(Data ->TheCurves[i]);
if (NewElem ->TheCurves[i] == NULL) goto Error;
}
return (void*) NewElem;
Error:
if (NewElem ->TheCurves != NULL) {
for (i=0; i < NewElem ->nCurves; i++) {
if (NewElem ->TheCurves[i])
cmsFreeToneCurve(Data ->TheCurves[i]);
}
}
_cmsFree(mpe ->ContextID, Data ->TheCurves);
_cmsFree(mpe ->ContextID, NewElem);
return NULL;
}
// Curves == NULL forces identity curves
cmsStage* CMSEXPORT cmsStageAllocToneCurves(cmsContext ContextID, cmsUInt32Number nChannels, cmsToneCurve* const Curves[])
{
cmsUInt32Number i;
_cmsStageToneCurvesData* NewElem;
cmsStage* NewMPE;
NewMPE = _cmsStageAllocPlaceholder(ContextID, cmsSigCurveSetElemType, nChannels, nChannels,
EvaluateCurves, CurveSetDup, CurveSetElemTypeFree, NULL );
if (NewMPE == NULL) return NULL;
NewElem = (_cmsStageToneCurvesData*) _cmsMalloc(ContextID, sizeof(_cmsStageToneCurvesData));
if (NewElem == NULL) {
cmsStageFree(NewMPE);
return NULL;
}
NewMPE ->Data = (void*) NewElem;
NewElem ->nCurves = nChannels;
NewElem ->TheCurves = (cmsToneCurve**) _cmsCalloc(ContextID, nChannels, sizeof(cmsToneCurve*));
if (NewElem ->TheCurves == NULL) {
cmsStageFree(NewMPE);
return NULL;
}
for (i=0; i < nChannels; i++) {
if (Curves == NULL) {
NewElem ->TheCurves[i] = cmsBuildGamma(ContextID, 1.0);
}
else {
NewElem ->TheCurves[i] = cmsDupToneCurve(Curves[i]);
}
if (NewElem ->TheCurves[i] == NULL) {
cmsStageFree(NewMPE);
return NULL;
}
}
return NewMPE;
}
// Create a bunch of identity curves
cmsStage* _cmsStageAllocIdentityCurves(cmsContext ContextID, int nChannels)
{
cmsStage* mpe = cmsStageAllocToneCurves(ContextID, nChannels, NULL);
if (mpe == NULL) return NULL;
mpe ->Implements = cmsSigIdentityElemType;
return mpe;
}
// *************************************************************************************************
// Type cmsSigMatrixElemType (Matrices)
// *************************************************************************************************
// Special care should be taken here because precision loss. A temporary cmsFloat64Number buffer is being used
static
void EvaluateMatrix(const cmsFloat32Number In[],
cmsFloat32Number Out[],
const cmsStage *mpe)
{
cmsUInt32Number i, j;
_cmsStageMatrixData* Data = (_cmsStageMatrixData*) mpe ->Data;
cmsFloat64Number Tmp;
// Input is already in 0..1.0 notation
for (i=0; i < mpe ->OutputChannels; i++) {
Tmp = 0;
for (j=0; j < mpe->InputChannels; j++) {
Tmp += In[j] * Data->Double[i*mpe->InputChannels + j];
}
if (Data ->Offset != NULL)
Tmp += Data->Offset[i];
Out[i] = (cmsFloat32Number) Tmp;
}
// Output in 0..1.0 domain
}
// Duplicate a yet-existing matrix element
static
void* MatrixElemDup(cmsStage* mpe)
{
_cmsStageMatrixData* Data = (_cmsStageMatrixData*) mpe ->Data;
_cmsStageMatrixData* NewElem;
cmsUInt32Number sz;
NewElem = (_cmsStageMatrixData*) _cmsMallocZero(mpe ->ContextID, sizeof(_cmsStageMatrixData));
if (NewElem == NULL) return NULL;
sz = mpe ->InputChannels * mpe ->OutputChannels;
NewElem ->Double = (cmsFloat64Number*) _cmsDupMem(mpe ->ContextID, Data ->Double, sz * sizeof(cmsFloat64Number)) ;
if (Data ->Offset)
NewElem ->Offset = (cmsFloat64Number*) _cmsDupMem(mpe ->ContextID,
Data ->Offset, mpe -> OutputChannels * sizeof(cmsFloat64Number)) ;
return (void*) NewElem;
}
static
void MatrixElemTypeFree(cmsStage* mpe)
{
_cmsStageMatrixData* Data = (_cmsStageMatrixData*) mpe ->Data;
if (Data ->Double)
_cmsFree(mpe ->ContextID, Data ->Double);
if (Data ->Offset)
_cmsFree(mpe ->ContextID, Data ->Offset);
_cmsFree(mpe ->ContextID, mpe ->Data);
}
cmsStage* CMSEXPORT cmsStageAllocMatrix(cmsContext ContextID, cmsUInt32Number Rows, cmsUInt32Number Cols,
const cmsFloat64Number* Matrix, const cmsFloat64Number* Offset)
{
cmsUInt32Number i, n;
_cmsStageMatrixData* NewElem;
cmsStage* NewMPE;
n = Rows * Cols;
// Check for overflow
if (n == 0) return NULL;
if (n >= UINT_MAX / Cols) return NULL;
if (n >= UINT_MAX / Rows) return NULL;
if (n < Rows || n < Cols) return NULL;
NewMPE = _cmsStageAllocPlaceholder(ContextID, cmsSigMatrixElemType, Cols, Rows,
EvaluateMatrix, MatrixElemDup, MatrixElemTypeFree, NULL );
if (NewMPE == NULL) return NULL;
NewElem = (_cmsStageMatrixData*) _cmsMallocZero(ContextID, sizeof(_cmsStageMatrixData));
if (NewElem == NULL) return NULL;
NewElem ->Double = (cmsFloat64Number*) _cmsCalloc(ContextID, n, sizeof(cmsFloat64Number));
if (NewElem->Double == NULL) {
MatrixElemTypeFree(NewMPE);
return NULL;
}
for (i=0; i < n; i++) {
NewElem ->Double[i] = Matrix[i];
}
if (Offset != NULL) {
NewElem ->Offset = (cmsFloat64Number*) _cmsCalloc(ContextID, Cols, sizeof(cmsFloat64Number));
if (NewElem->Offset == NULL) {
MatrixElemTypeFree(NewMPE);
return NULL;
}
for (i=0; i < Cols; i++) {
NewElem ->Offset[i] = Offset[i];
}
}
NewMPE ->Data = (void*) NewElem;
return NewMPE;
}
// *************************************************************************************************
// Type cmsSigCLutElemType
// *************************************************************************************************
// Evaluate in true floating point
static
void EvaluateCLUTfloat(const cmsFloat32Number In[], cmsFloat32Number Out[], const cmsStage *mpe)
{
_cmsStageCLutData* Data = (_cmsStageCLutData*) mpe ->Data;
Data -> Params ->Interpolation.LerpFloat(In, Out, Data->Params);
}
// Convert to 16 bits, evaluate, and back to floating point
static
void EvaluateCLUTfloatIn16(const cmsFloat32Number In[], cmsFloat32Number Out[], const cmsStage *mpe)
{
_cmsStageCLutData* Data = (_cmsStageCLutData*) mpe ->Data;
cmsUInt16Number In16[MAX_STAGE_CHANNELS], Out16[MAX_STAGE_CHANNELS];
_cmsAssert(mpe ->InputChannels <= MAX_STAGE_CHANNELS);
_cmsAssert(mpe ->OutputChannels <= MAX_STAGE_CHANNELS);
FromFloatTo16(In, In16, mpe ->InputChannels);
Data -> Params ->Interpolation.Lerp16(In16, Out16, Data->Params);
From16ToFloat(Out16, Out, mpe ->OutputChannels);
}
// Given an hypercube of b dimensions, with Dims[] number of nodes by dimension, calculate the total amount of nodes
static
cmsUInt32Number CubeSize(const cmsUInt32Number Dims[], cmsUInt32Number b)
{
cmsUInt32Number rv, dim;
_cmsAssert(Dims != NULL);
for (rv = 1; b > 0; b--) {
dim = Dims[b-1];
if (dim == 0) return 0; // Error
rv *= dim;
// Check for overflow
if (rv > UINT_MAX / dim) return 0;
}
return rv;
}
static
void* CLUTElemDup(cmsStage* mpe)
{
_cmsStageCLutData* Data = (_cmsStageCLutData*) mpe ->Data;
_cmsStageCLutData* NewElem;
NewElem = (_cmsStageCLutData*) _cmsMallocZero(mpe ->ContextID, sizeof(_cmsStageCLutData));
if (NewElem == NULL) return NULL;
NewElem ->nEntries = Data ->nEntries;
NewElem ->HasFloatValues = Data ->HasFloatValues;
if (Data ->Tab.T) {
if (Data ->HasFloatValues)
NewElem ->Tab.TFloat = (cmsFloat32Number*) _cmsDupMem(mpe ->ContextID, Data ->Tab.TFloat, Data ->nEntries * sizeof (cmsFloat32Number));
else
NewElem ->Tab.T = (cmsUInt16Number*) _cmsDupMem(mpe ->ContextID, Data ->Tab.T, Data ->nEntries * sizeof (cmsUInt16Number));
}
NewElem ->Params = _cmsComputeInterpParamsEx(mpe ->ContextID,
Data ->Params ->nSamples,
Data ->Params ->nInputs,
Data ->Params ->nOutputs,
NewElem ->Tab.T,
Data ->Params ->dwFlags);
return (void*) NewElem;
}
static
void CLutElemTypeFree(cmsStage* mpe)
{
_cmsStageCLutData* Data = (_cmsStageCLutData*) mpe ->Data;
// Already empty
if (Data == NULL) return;
// This works for both types
if (Data -> Tab.T)
_cmsFree(mpe ->ContextID, Data -> Tab.T);
_cmsFreeInterpParams(Data ->Params);
_cmsFree(mpe ->ContextID, mpe ->Data);
}
// Allocates a 16-bit multidimensional CLUT. This is evaluated at 16-bit precision. Table may have different
// granularity on each dimension.
cmsStage* CMSEXPORT cmsStageAllocCLut16bitGranular(cmsContext ContextID,
const cmsUInt32Number clutPoints[],
cmsUInt32Number inputChan,
cmsUInt32Number outputChan,
const cmsUInt16Number* Table)
{
cmsUInt32Number i, n;
_cmsStageCLutData* NewElem;
cmsStage* NewMPE;
NewMPE = _cmsStageAllocPlaceholder(ContextID, cmsSigCLutElemType, inputChan, outputChan,
EvaluateCLUTfloatIn16, CLUTElemDup, CLutElemTypeFree, NULL );
if (NewMPE == NULL) return NULL;
NewElem = (_cmsStageCLutData*) _cmsMalloc(ContextID, sizeof(_cmsStageCLutData));
if (NewElem == NULL) {
cmsStageFree(NewMPE);
return NULL;
}
NewMPE ->Data = (void*) NewElem;
NewElem -> nEntries = n = outputChan * CubeSize(clutPoints, inputChan);
NewElem -> HasFloatValues = FALSE;
if (n == 0) {
cmsStageFree(NewMPE);
return NULL;
}
NewElem ->Tab.T = (cmsUInt16Number*) _cmsCalloc(ContextID, n, sizeof(cmsUInt16Number));
if (NewElem ->Tab.T == NULL) {
cmsStageFree(NewMPE);
return NULL;
}
if (Table != NULL) {
for (i=0; i < n; i++) {
NewElem ->Tab.T[i] = Table[i];
}
}
NewElem ->Params = _cmsComputeInterpParamsEx(ContextID, clutPoints, inputChan, outputChan, NewElem ->Tab.T, CMS_LERP_FLAGS_16BITS);
if (NewElem ->Params == NULL) {
cmsStageFree(NewMPE);
return NULL;
}
return NewMPE;
}
cmsStage* CMSEXPORT cmsStageAllocCLut16bit(cmsContext ContextID,
cmsUInt32Number nGridPoints,
cmsUInt32Number inputChan,
cmsUInt32Number outputChan,
const cmsUInt16Number* Table)
{
cmsUInt32Number Dimensions[MAX_INPUT_DIMENSIONS];
int i;
// Our resulting LUT would be same gridpoints on all dimensions
for (i=0; i < MAX_INPUT_DIMENSIONS; i++)
Dimensions[i] = nGridPoints;
return cmsStageAllocCLut16bitGranular(ContextID, Dimensions, inputChan, outputChan, Table);
}
cmsStage* CMSEXPORT cmsStageAllocCLutFloat(cmsContext ContextID,
cmsUInt32Number nGridPoints,
cmsUInt32Number inputChan,
cmsUInt32Number outputChan,
const cmsFloat32Number* Table)
{
cmsUInt32Number Dimensions[MAX_INPUT_DIMENSIONS];
int i;
// Our resulting LUT would be same gridpoints on all dimensions
for (i=0; i < MAX_INPUT_DIMENSIONS; i++)
Dimensions[i] = nGridPoints;
return cmsStageAllocCLutFloatGranular(ContextID, Dimensions, inputChan, outputChan, Table);
}
cmsStage* CMSEXPORT cmsStageAllocCLutFloatGranular(cmsContext ContextID, const cmsUInt32Number clutPoints[], cmsUInt32Number inputChan, cmsUInt32Number outputChan, const cmsFloat32Number* Table)
{
cmsUInt32Number i, n;
_cmsStageCLutData* NewElem;
cmsStage* NewMPE;
_cmsAssert(clutPoints != NULL);
NewMPE = _cmsStageAllocPlaceholder(ContextID, cmsSigCLutElemType, inputChan, outputChan,
EvaluateCLUTfloat, CLUTElemDup, CLutElemTypeFree, NULL);
if (NewMPE == NULL) return NULL;
NewElem = (_cmsStageCLutData*) _cmsMalloc(ContextID, sizeof(_cmsStageCLutData));
if (NewElem == NULL) {
cmsStageFree(NewMPE);
return NULL;
}
NewMPE ->Data = (void*) NewElem;
// There is a potential integer overflow on conputing n and nEntries.
NewElem -> nEntries = n = outputChan * CubeSize( clutPoints, inputChan);
NewElem -> HasFloatValues = TRUE;
if (n == 0) {
cmsStageFree(NewMPE);
return NULL;
}
NewElem ->Tab.TFloat = (cmsFloat32Number*) _cmsCalloc(ContextID, n, sizeof(cmsFloat32Number));
if (NewElem ->Tab.TFloat == NULL) {
cmsStageFree(NewMPE);
return NULL;
}
if (Table != NULL) {
for (i=0; i < n; i++) {
NewElem ->Tab.TFloat[i] = Table[i];
}
}
NewElem ->Params = _cmsComputeInterpParamsEx(ContextID, clutPoints, inputChan, outputChan, NewElem ->Tab.TFloat, CMS_LERP_FLAGS_FLOAT);
if (NewElem ->Params == NULL) {
cmsStageFree(NewMPE);
return NULL;
}
return NewMPE;
}
static
int IdentitySampler(register const cmsUInt16Number In[], register cmsUInt16Number Out[], register void * Cargo)
{
int nChan = *(int*) Cargo;
int i;
for (i=0; i < nChan; i++)
Out[i] = In[i];
return 1;
}
// Creates an MPE that just copies input to output
cmsStage* _cmsStageAllocIdentityCLut(cmsContext ContextID, int nChan)
{
cmsUInt32Number Dimensions[MAX_INPUT_DIMENSIONS];
cmsStage* mpe ;
int i;
for (i=0; i < MAX_INPUT_DIMENSIONS; i++)
Dimensions[i] = 2;
mpe = cmsStageAllocCLut16bitGranular(ContextID, Dimensions, nChan, nChan, NULL);
if (mpe == NULL) return NULL;
if (!cmsStageSampleCLut16bit(mpe, IdentitySampler, &nChan, 0)) {
cmsStageFree(mpe);
return NULL;
}
mpe ->Implements = cmsSigIdentityElemType;
return mpe;
}
// Quantize a value 0 <= i < MaxSamples to 0..0xffff
cmsUInt16Number _cmsQuantizeVal(cmsFloat64Number i, int MaxSamples)
{
cmsFloat64Number x;
x = ((cmsFloat64Number) i * 65535.) / (cmsFloat64Number) (MaxSamples - 1);
return _cmsQuickSaturateWord(x);
}
// This routine does a sweep on whole input space, and calls its callback
// function on knots. returns TRUE if all ok, FALSE otherwise.
cmsBool CMSEXPORT cmsStageSampleCLut16bit(cmsStage* mpe, cmsSAMPLER16 Sampler, void * Cargo, cmsUInt32Number dwFlags)
{
int i, t, nTotalPoints, index, rest;
int nInputs, nOutputs;
cmsUInt32Number* nSamples;
cmsUInt16Number In[cmsMAXCHANNELS], Out[MAX_STAGE_CHANNELS];
_cmsStageCLutData* clut = (_cmsStageCLutData*) mpe->Data;
nSamples = clut->Params ->nSamples;
nInputs = clut->Params ->nInputs;
nOutputs = clut->Params ->nOutputs;
if (nInputs >= cmsMAXCHANNELS) return FALSE;
if (nOutputs >= MAX_STAGE_CHANNELS) return FALSE;
nTotalPoints = CubeSize(nSamples, nInputs);
if (nTotalPoints == 0) return FALSE;
index = 0;
for (i = 0; i < nTotalPoints; i++) {
rest = i;
for (t = nInputs-1; t >=0; --t) {
cmsUInt32Number Colorant = rest % nSamples[t];
rest /= nSamples[t];
In[t] = _cmsQuantizeVal(Colorant, nSamples[t]);
}
if (clut ->Tab.T != NULL) {
for (t=0; t < nOutputs; t++)
Out[t] = clut->Tab.T[index + t];
}
if (!Sampler(In, Out, Cargo))
return FALSE;
if (!(dwFlags & SAMPLER_INSPECT)) {
if (clut ->Tab.T != NULL) {
for (t=0; t < nOutputs; t++)
clut->Tab.T[index + t] = Out[t];
}
}
index += nOutputs;
}
return TRUE;
}
// Same as anterior, but for floting point
cmsBool CMSEXPORT cmsStageSampleCLutFloat(cmsStage* mpe, cmsSAMPLERFLOAT Sampler, void * Cargo, cmsUInt32Number dwFlags)
{
int i, t, nTotalPoints, index, rest;
int nInputs, nOutputs;
cmsUInt32Number* nSamples;
cmsFloat32Number In[cmsMAXCHANNELS], Out[MAX_STAGE_CHANNELS];
_cmsStageCLutData* clut = (_cmsStageCLutData*) mpe->Data;
nSamples = clut->Params ->nSamples;
nInputs = clut->Params ->nInputs;
nOutputs = clut->Params ->nOutputs;
if (nInputs >= cmsMAXCHANNELS) return FALSE;
if (nOutputs >= MAX_STAGE_CHANNELS) return FALSE;
nTotalPoints = CubeSize(nSamples, nInputs);
if (nTotalPoints == 0) return FALSE;
index = 0;
for (i = 0; i < nTotalPoints; i++) {
rest = i;
for (t = nInputs-1; t >=0; --t) {
cmsUInt32Number Colorant = rest % nSamples[t];
rest /= nSamples[t];
In[t] = (cmsFloat32Number) (_cmsQuantizeVal(Colorant, nSamples[t]) / 65535.0);
}
if (clut ->Tab.TFloat != NULL) {
for (t=0; t < nOutputs; t++)
Out[t] = clut->Tab.TFloat[index + t];
}
if (!Sampler(In, Out, Cargo))
return FALSE;
if (!(dwFlags & SAMPLER_INSPECT)) {
if (clut ->Tab.TFloat != NULL) {
for (t=0; t < nOutputs; t++)
clut->Tab.TFloat[index + t] = Out[t];
}
}
index += nOutputs;
}
return TRUE;
}
// This routine does a sweep on whole input space, and calls its callback
// function on knots. returns TRUE if all ok, FALSE otherwise.
cmsBool CMSEXPORT cmsSliceSpace16(cmsUInt32Number nInputs, const cmsUInt32Number clutPoints[],
cmsSAMPLER16 Sampler, void * Cargo)
{
int i, t, nTotalPoints, rest;
cmsUInt16Number In[cmsMAXCHANNELS];
if (nInputs >= cmsMAXCHANNELS) return FALSE;
nTotalPoints = CubeSize(clutPoints, nInputs);
if (nTotalPoints == 0) return FALSE;
for (i = 0; i < nTotalPoints; i++) {
rest = i;
for (t = nInputs-1; t >=0; --t) {
cmsUInt32Number Colorant = rest % clutPoints[t];
rest /= clutPoints[t];
In[t] = _cmsQuantizeVal(Colorant, clutPoints[t]);
}
if (!Sampler(In, NULL, Cargo))
return FALSE;
}
return TRUE;
}
cmsInt32Number CMSEXPORT cmsSliceSpaceFloat(cmsUInt32Number nInputs, const cmsUInt32Number clutPoints[],
cmsSAMPLERFLOAT Sampler, void * Cargo)
{
int i, t, nTotalPoints, rest;
cmsFloat32Number In[cmsMAXCHANNELS];
if (nInputs >= cmsMAXCHANNELS) return FALSE;
nTotalPoints = CubeSize(clutPoints, nInputs);
if (nTotalPoints == 0) return FALSE;
for (i = 0; i < nTotalPoints; i++) {
rest = i;
for (t = nInputs-1; t >=0; --t) {
cmsUInt32Number Colorant = rest % clutPoints[t];
rest /= clutPoints[t];
In[t] = (cmsFloat32Number) (_cmsQuantizeVal(Colorant, clutPoints[t]) / 65535.0);
}
if (!Sampler(In, NULL, Cargo))
return FALSE;
}
return TRUE;
}
// ********************************************************************************
// Type cmsSigLab2XYZElemType
// ********************************************************************************
static
void EvaluateLab2XYZ(const cmsFloat32Number In[],
cmsFloat32Number Out[],
const cmsStage *mpe)
{
cmsCIELab Lab;
cmsCIEXYZ XYZ;
const cmsFloat64Number XYZadj = MAX_ENCODEABLE_XYZ;
// V4 rules
Lab.L = In[0] * 100.0;
Lab.a = In[1] * 255.0 - 128.0;
Lab.b = In[2] * 255.0 - 128.0;
cmsLab2XYZ(NULL, &XYZ, &Lab);
// From XYZ, range 0..19997 to 0..1.0, note that 1.99997 comes from 0xffff
// encoded as 1.15 fixed point, so 1 + (32767.0 / 32768.0)
Out[0] = (cmsFloat32Number) ((cmsFloat64Number) XYZ.X / XYZadj);
Out[1] = (cmsFloat32Number) ((cmsFloat64Number) XYZ.Y / XYZadj);
Out[2] = (cmsFloat32Number) ((cmsFloat64Number) XYZ.Z / XYZadj);
return;
cmsUNUSED_PARAMETER(mpe);
}
// No dup or free routines needed, as the structure has no pointers in it.
cmsStage* _cmsStageAllocLab2XYZ(cmsContext ContextID)
{
return _cmsStageAllocPlaceholder(ContextID, cmsSigLab2XYZElemType, 3, 3, EvaluateLab2XYZ, NULL, NULL, NULL);
}
// ********************************************************************************
// v2 L=100 is supposed to be placed on 0xFF00. There is no reasonable
// number of gridpoints that would make exact match. However, a prelinearization
// of 258 entries, would map 0xFF00 exactly on entry 257, and this is good to avoid scum dot.
// Almost all what we need but unfortunately, the rest of entries should be scaled by
// (255*257/256) and this is not exact.
cmsStage* _cmsStageAllocLabV2ToV4curves(cmsContext ContextID)
{
cmsStage* mpe;
cmsToneCurve* LabTable[3];
int i, j;
LabTable[0] = cmsBuildTabulatedToneCurve16(ContextID, 258, NULL);
LabTable[1] = cmsBuildTabulatedToneCurve16(ContextID, 258, NULL);
LabTable[2] = cmsBuildTabulatedToneCurve16(ContextID, 258, NULL);
for (j=0; j < 3; j++) {
if (LabTable[j] == NULL) {
cmsFreeToneCurveTriple(LabTable);
return NULL;
}
// We need to map * (0xffff / 0xff00), thats same as (257 / 256)
// So we can use 258-entry tables to do the trick (i / 257) * (255 * 257) * (257 / 256);
for (i=0; i < 257; i++) {
LabTable[j]->Table16[i] = (cmsUInt16Number) ((i * 0xffff + 0x80) >> 8);
}
LabTable[j] ->Table16[257] = 0xffff;
}
mpe = cmsStageAllocToneCurves(ContextID, 3, LabTable);
cmsFreeToneCurveTriple(LabTable);
mpe ->Implements = cmsSigLabV2toV4;
return mpe;
}
// ********************************************************************************
// Matrix-based conversion, which is more accurate, but slower and cannot properly be saved in devicelink profiles
cmsStage* _cmsStageAllocLabV2ToV4(cmsContext ContextID)
{
static const cmsFloat64Number V2ToV4[] = { 65535.0/65280.0, 0, 0,
0, 65535.0/65280.0, 0,
0, 0, 65535.0/65280.0
};
cmsStage *mpe = cmsStageAllocMatrix(ContextID, 3, 3, V2ToV4, NULL);
if (mpe == NULL) return mpe;
mpe ->Implements = cmsSigLabV2toV4;
return mpe;
}
// Reverse direction
cmsStage* _cmsStageAllocLabV4ToV2(cmsContext ContextID)
{
static const cmsFloat64Number V4ToV2[] = { 65280.0/65535.0, 0, 0,
0, 65280.0/65535.0, 0,
0, 0, 65280.0/65535.0
};
cmsStage *mpe = cmsStageAllocMatrix(ContextID, 3, 3, V4ToV2, NULL);
if (mpe == NULL) return mpe;
mpe ->Implements = cmsSigLabV4toV2;
return mpe;
}
// ********************************************************************************
// Type cmsSigXYZ2LabElemType
// ********************************************************************************
static
void EvaluateXYZ2Lab(const cmsFloat32Number In[], cmsFloat32Number Out[], const cmsStage *mpe)
{
cmsCIELab Lab;
cmsCIEXYZ XYZ;
const cmsFloat64Number XYZadj = MAX_ENCODEABLE_XYZ;
// From 0..1.0 to XYZ
XYZ.X = In[0] * XYZadj;
XYZ.Y = In[1] * XYZadj;
XYZ.Z = In[2] * XYZadj;
cmsXYZ2Lab(NULL, &Lab, &XYZ);
// From V4 Lab to 0..1.0
Out[0] = (cmsFloat32Number) (Lab.L / 100.0);
Out[1] = (cmsFloat32Number) ((Lab.a + 128.0) / 255.0);
Out[2] = (cmsFloat32Number) ((Lab.b + 128.0) / 255.0);
return;
cmsUNUSED_PARAMETER(mpe);
}
cmsStage* _cmsStageAllocXYZ2Lab(cmsContext ContextID)
{
return _cmsStageAllocPlaceholder(ContextID, cmsSigXYZ2LabElemType, 3, 3, EvaluateXYZ2Lab, NULL, NULL, NULL);
}
// ********************************************************************************
// For v4, S-Shaped curves are placed in a/b axis to increase resolution near gray
cmsStage* _cmsStageAllocLabPrelin(cmsContext ContextID)
{
cmsToneCurve* LabTable[3];
cmsFloat64Number Params[1] = {2.4} ;
LabTable[0] = cmsBuildGamma(ContextID, 1.0);
LabTable[1] = cmsBuildParametricToneCurve(ContextID, 108, Params);
LabTable[2] = cmsBuildParametricToneCurve(ContextID, 108, Params);
return cmsStageAllocToneCurves(ContextID, 3, LabTable);
}
// Free a single MPE
void CMSEXPORT cmsStageFree(cmsStage* mpe)
{
if (mpe ->FreePtr)
mpe ->FreePtr(mpe);
_cmsFree(mpe ->ContextID, mpe);
}
cmsUInt32Number CMSEXPORT cmsStageInputChannels(const cmsStage* mpe)
{
return mpe ->InputChannels;
}
cmsUInt32Number CMSEXPORT cmsStageOutputChannels(const cmsStage* mpe)
{
return mpe ->OutputChannels;
}
cmsStageSignature CMSEXPORT cmsStageType(const cmsStage* mpe)
{
return mpe -> Type;
}
void* CMSEXPORT cmsStageData(const cmsStage* mpe)
{
return mpe -> Data;
}
cmsStage* CMSEXPORT cmsStageNext(const cmsStage* mpe)
{
return mpe -> Next;
}
// Duplicates an MPE
cmsStage* CMSEXPORT cmsStageDup(cmsStage* mpe)
{
cmsStage* NewMPE;
if (mpe == NULL) return NULL;
NewMPE = _cmsStageAllocPlaceholder(mpe ->ContextID,
mpe ->Type,
mpe ->InputChannels,
mpe ->OutputChannels,
mpe ->EvalPtr,
mpe ->DupElemPtr,
mpe ->FreePtr,
NULL);
if (NewMPE == NULL) return NULL;
NewMPE ->Implements = mpe ->Implements;
if (mpe ->DupElemPtr)
NewMPE ->Data = mpe ->DupElemPtr(mpe);
else
NewMPE ->Data = NULL;
return NewMPE;
}
// ***********************************************************************************************************
// This function sets up the channel count
static
void BlessLUT(cmsPipeline* lut)
{
// We can set the input/ouput channels only if we have elements.
if (lut ->Elements != NULL) {
cmsStage *First, *Last;
First = cmsPipelineGetPtrToFirstStage(lut);
Last = cmsPipelineGetPtrToLastStage(lut);
if (First != NULL)lut ->InputChannels = First ->InputChannels;
if (Last != NULL) lut ->OutputChannels = Last ->OutputChannels;
}
}
// Default to evaluate the LUT on 16 bit-basis. Precision is retained.
static
void _LUTeval16(register const cmsUInt16Number In[], register cmsUInt16Number Out[], register const void* D)
{
cmsPipeline* lut = (cmsPipeline*) D;
cmsStage *mpe;
cmsFloat32Number Storage[2][MAX_STAGE_CHANNELS];
int Phase = 0, NextPhase;
From16ToFloat(In, &Storage[Phase][0], lut ->InputChannels);
for (mpe = lut ->Elements;
mpe != NULL;
mpe = mpe ->Next) {
NextPhase = Phase ^ 1;
mpe ->EvalPtr(&Storage[Phase][0], &Storage[NextPhase][0], mpe);
Phase = NextPhase;
}
FromFloatTo16(&Storage[Phase][0], Out, lut ->OutputChannels);
}
// Does evaluate the LUT on cmsFloat32Number-basis.
static
void _LUTevalFloat(register const cmsFloat32Number In[], register cmsFloat32Number Out[], const void* D)
{
cmsPipeline* lut = (cmsPipeline*) D;
cmsStage *mpe;
cmsFloat32Number Storage[2][MAX_STAGE_CHANNELS];
int Phase = 0, NextPhase;
memmove(&Storage[Phase][0], In, lut ->InputChannels * sizeof(cmsFloat32Number));
for (mpe = lut ->Elements;
mpe != NULL;
mpe = mpe ->Next) {
NextPhase = Phase ^ 1;
mpe ->EvalPtr(&Storage[Phase][0], &Storage[NextPhase][0], mpe);
Phase = NextPhase;
}
memmove(Out, &Storage[Phase][0], lut ->OutputChannels * sizeof(cmsFloat32Number));
}
// LUT Creation & Destruction
cmsPipeline* CMSEXPORT cmsPipelineAlloc(cmsContext ContextID, cmsUInt32Number InputChannels, cmsUInt32Number OutputChannels)
{
cmsPipeline* NewLUT;
if (InputChannels >= cmsMAXCHANNELS ||
OutputChannels >= cmsMAXCHANNELS) return NULL;
NewLUT = (cmsPipeline*) _cmsMallocZero(ContextID, sizeof(cmsPipeline));
if (NewLUT == NULL) return NULL;
NewLUT -> InputChannels = InputChannels;
NewLUT -> OutputChannels = OutputChannels;
NewLUT ->Eval16Fn = _LUTeval16;
NewLUT ->EvalFloatFn = _LUTevalFloat;
NewLUT ->DupDataFn = NULL;
NewLUT ->FreeDataFn = NULL;
NewLUT ->Data = NewLUT;
NewLUT ->ContextID = ContextID;
BlessLUT(NewLUT);
return NewLUT;
}
cmsUInt32Number CMSEXPORT cmsPipelineInputChannels(const cmsPipeline* lut)
{
return lut ->InputChannels;
}
cmsUInt32Number CMSEXPORT cmsPipelineOutputChannels(const cmsPipeline* lut)
{
return lut ->OutputChannels;
}
// Free a profile elements LUT
void CMSEXPORT cmsPipelineFree(cmsPipeline* lut)
{
cmsStage *mpe, *Next;
if (lut == NULL) return;
for (mpe = lut ->Elements;
mpe != NULL;
mpe = Next) {
Next = mpe ->Next;
cmsStageFree(mpe);
}
if (lut ->FreeDataFn) lut ->FreeDataFn(lut ->ContextID, lut ->Data);
_cmsFree(lut ->ContextID, lut);
}
// Default to evaluate the LUT on 16 bit-basis.
void CMSEXPORT cmsPipelineEval16(const cmsUInt16Number In[], cmsUInt16Number Out[], const cmsPipeline* lut)
{
lut ->Eval16Fn(In, Out, lut->Data);
}
// Does evaluate the LUT on cmsFloat32Number-basis.
void CMSEXPORT cmsPipelineEvalFloat(const cmsFloat32Number In[], cmsFloat32Number Out[], const cmsPipeline* lut)
{
lut ->EvalFloatFn(In, Out, lut);
}
// Duplicates a LUT
cmsPipeline* CMSEXPORT cmsPipelineDup(const cmsPipeline* lut)
{
cmsPipeline* NewLUT;
cmsStage *NewMPE, *Anterior = NULL, *mpe;
cmsBool First = TRUE;
if (lut == NULL) return NULL;
NewLUT = cmsPipelineAlloc(lut ->ContextID, lut ->InputChannels, lut ->OutputChannels);
for (mpe = lut ->Elements;
mpe != NULL;
mpe = mpe ->Next) {
NewMPE = cmsStageDup(mpe);
if (NewMPE == NULL) {
cmsPipelineFree(NewLUT);
return NULL;
}
if (First) {
NewLUT ->Elements = NewMPE;
First = FALSE;
}
else {
Anterior ->Next = NewMPE;
}
Anterior = NewMPE;
}
NewLUT ->DupDataFn = lut ->DupDataFn;
NewLUT ->FreeDataFn = lut ->FreeDataFn;
if (NewLUT ->DupDataFn != NULL)
NewLUT ->Data = NewLUT ->DupDataFn(lut ->ContextID, lut->Data);
NewLUT ->SaveAs8Bits = lut ->SaveAs8Bits;
BlessLUT(NewLUT);
return NewLUT;
}
void CMSEXPORT cmsPipelineInsertStage(cmsPipeline* lut, cmsStageLoc loc, cmsStage* mpe)
{
cmsStage* Anterior = NULL, *pt;
_cmsAssert(lut != NULL);
_cmsAssert(mpe != NULL);
switch (loc) {
case cmsAT_BEGIN:
mpe ->Next = lut ->Elements;
lut ->Elements = mpe;
break;
case cmsAT_END:
if (lut ->Elements == NULL)
lut ->Elements = mpe;
else {
for (pt = lut ->Elements;
pt != NULL;
pt = pt -> Next) Anterior = pt;
Anterior ->Next = mpe;
mpe ->Next = NULL;
}
break;
default:;
}
BlessLUT(lut);
}
// Unlink an element and return the pointer to it
void CMSEXPORT cmsPipelineUnlinkStage(cmsPipeline* lut, cmsStageLoc loc, cmsStage** mpe)
{
cmsStage *Anterior, *pt, *Last;
cmsStage *Unlinked = NULL;
// If empty LUT, there is nothing to remove
if (lut ->Elements == NULL) {
if (mpe) *mpe = NULL;
return;
}
// On depending on the strategy...
switch (loc) {
case cmsAT_BEGIN:
{
cmsStage* elem = lut ->Elements;
lut ->Elements = elem -> Next;
elem ->Next = NULL;
Unlinked = elem;
}
break;
case cmsAT_END:
Anterior = Last = NULL;
for (pt = lut ->Elements;
pt != NULL;
pt = pt -> Next) {
Anterior = Last;
Last = pt;
}
Unlinked = Last; // Next already points to NULL
// Truncate the chain
if (Anterior)
Anterior ->Next = NULL;
else
lut ->Elements = NULL;
break;
default:;
}
if (mpe)
*mpe = Unlinked;
else
cmsStageFree(Unlinked);
BlessLUT(lut);
}
// Concatenate two LUT into a new single one
cmsBool CMSEXPORT cmsPipelineCat(cmsPipeline* l1, const cmsPipeline* l2)
{
cmsStage* mpe, *NewMPE;
// If both LUTS does not have elements, we need to inherit
// the number of channels
if (l1 ->Elements == NULL && l2 ->Elements == NULL) {
l1 ->InputChannels = l2 ->InputChannels;
l1 ->OutputChannels = l2 ->OutputChannels;
}
// Cat second
for (mpe = l2 ->Elements;
mpe != NULL;
mpe = mpe ->Next) {
// We have to dup each element
NewMPE = cmsStageDup(mpe);
if (NewMPE == NULL) {
return FALSE;
}
cmsPipelineInsertStage(l1, cmsAT_END, NewMPE);
}
BlessLUT(l1);
return TRUE;
}
cmsBool CMSEXPORT cmsPipelineSetSaveAs8bitsFlag(cmsPipeline* lut, cmsBool On)
{
cmsBool Anterior = lut ->SaveAs8Bits;
lut ->SaveAs8Bits = On;
return Anterior;
}
cmsStage* CMSEXPORT cmsPipelineGetPtrToFirstStage(const cmsPipeline* lut)
{
return lut ->Elements;
}
cmsStage* CMSEXPORT cmsPipelineGetPtrToLastStage(const cmsPipeline* lut)
{
cmsStage *mpe, *Anterior = NULL;
for (mpe = lut ->Elements; mpe != NULL; mpe = mpe ->Next)
Anterior = mpe;
return Anterior;
}
cmsUInt32Number CMSEXPORT cmsPipelineStageCount(const cmsPipeline* lut)
{
cmsStage *mpe;
cmsUInt32Number n;
for (n=0, mpe = lut ->Elements; mpe != NULL; mpe = mpe ->Next)
n++;
return n;
}
// This function may be used to set the optional evalueator and a block of private data. If private data is being used, an optional
// duplicator and free functions should also be specified in order to duplicate the LUT construct. Use NULL to inhibit such functionality.
void CMSEXPORT _cmsPipelineSetOptimizationParameters(cmsPipeline* Lut,
_cmsOPTeval16Fn Eval16,
void* PrivateData,
_cmsOPTfreeDataFn FreePrivateDataFn,
_cmsOPTdupDataFn DupPrivateDataFn)
{
Lut ->Eval16Fn = Eval16;
Lut ->DupDataFn = DupPrivateDataFn;
Lut ->FreeDataFn = FreePrivateDataFn;
Lut ->Data = PrivateData;
}
// ----------------------------------------------------------- Reverse interpolation
// Here's how it goes. The derivative Df(x) of the function f is the linear
// transformation that best approximates f near the point x. It can be represented
// by a matrix A whose entries are the partial derivatives of the components of f
// with respect to all the coordinates. This is know as the Jacobian
//
// The best linear approximation to f is given by the matrix equation:
//
// y-y0 = A (x-x0)
//
// So, if x0 is a good "guess" for the zero of f, then solving for the zero of this
// linear approximation will give a "better guess" for the zero of f. Thus let y=0,
// and since y0=f(x0) one can solve the above equation for x. This leads to the
// Newton's method formula:
//
// xn+1 = xn - A-1 f(xn)
//
// where xn+1 denotes the (n+1)-st guess, obtained from the n-th guess xn in the
// fashion described above. Iterating this will give better and better approximations
// if you have a "good enough" initial guess.
#define JACOBIAN_EPSILON 0.001f
#define INVERSION_MAX_ITERATIONS 30
// Increment with reflexion on boundary
static
void IncDelta(cmsFloat32Number *Val)
{
if (*Val < (1.0 - JACOBIAN_EPSILON))
*Val += JACOBIAN_EPSILON;
else
*Val -= JACOBIAN_EPSILON;
}
// Euclidean distance between two vectors of n elements each one
static
cmsFloat32Number EuclideanDistance(cmsFloat32Number a[], cmsFloat32Number b[], int n)
{
cmsFloat32Number sum = 0;
int i;
for (i=0; i < n; i++) {
cmsFloat32Number dif = b[i] - a[i];
sum += dif * dif;
}
return sqrtf(sum);
}
// Evaluate a LUT in reverse direction. It only searches on 3->3 LUT. Uses Newton method
//
// x1 <- x - [J(x)]^-1 * f(x)
//
// lut: The LUT on where to do the search
// Target: LabK, 3 values of Lab plus destination K which is fixed
// Result: The obtained CMYK
// Hint: Location where begin the search
cmsBool CMSEXPORT cmsPipelineEvalReverseFloat(cmsFloat32Number Target[],
cmsFloat32Number Result[],
cmsFloat32Number Hint[],
const cmsPipeline* lut)
{
cmsUInt32Number i, j;
cmsFloat64Number error, LastError = 1E20;
cmsFloat32Number fx[4], x[4], xd[4], fxd[4];
cmsVEC3 tmp, tmp2;
cmsMAT3 Jacobian;
cmsFloat64Number LastResult[4];
// Only 3->3 and 4->3 are supported
if (lut ->InputChannels != 3 && lut ->InputChannels != 4) return FALSE;
if (lut ->OutputChannels != 3) return FALSE;
// Mark result of -1
LastResult[0] = LastResult[1] = LastResult[2] = -1.0f;
// Take the hint as starting point if specified
if (Hint == NULL) {
// Begin at any point, we choose 1/3 of CMY axis
x[0] = x[1] = x[2] = 0.3f;
}
else {
// Only copy 3 channels from hint...
for (j=0; j < 3; j++)
x[j] = Hint[j];
}
// If Lut is 4-dimensions, then grab target[3], which is fixed
if (lut ->InputChannels == 4) {
x[3] = Target[3];
}
else x[3] = 0; // To keep lint happy
// Iterate
for (i = 0; i < INVERSION_MAX_ITERATIONS; i++) {
// Get beginning fx
cmsPipelineEvalFloat(x, fx, lut);
// Compute error
error = EuclideanDistance(fx, Target, 3);
// If not convergent, return last safe value
if (error >= LastError)
break;
// Keep latest values
LastError = error;
for (j=0; j < lut ->InputChannels; j++)
Result[j] = x[j];
// Found an exact match?
if (error <= 0)
break;
// Obtain slope (the Jacobian)
for (j = 0; j < 3; j++) {
xd[0] = x[0];
xd[1] = x[1];
xd[2] = x[2];
xd[3] = x[3]; // Keep fixed channel
IncDelta(&xd[j]);
cmsPipelineEvalFloat(xd, fxd, lut);
Jacobian.v[0].n[j] = ((fxd[0] - fx[0]) / JACOBIAN_EPSILON);
Jacobian.v[1].n[j] = ((fxd[1] - fx[1]) / JACOBIAN_EPSILON);
Jacobian.v[2].n[j] = ((fxd[2] - fx[2]) / JACOBIAN_EPSILON);
}
// Solve system
tmp2.n[0] = fx[0] - Target[0];
tmp2.n[1] = fx[1] - Target[1];
tmp2.n[2] = fx[2] - Target[2];
if (!_cmsMAT3solve(&tmp, &Jacobian, &tmp2))
return FALSE;
// Move our guess
x[0] -= (cmsFloat32Number) tmp.n[0];
x[1] -= (cmsFloat32Number) tmp.n[1];
x[2] -= (cmsFloat32Number) tmp.n[2];
// Some clipping....
for (j=0; j < 3; j++) {
if (x[j] < 0) x[j] = 0;
else
if (x[j] > 1.0) x[j] = 1.0;
}
}
return TRUE;
}