//---------------------------------------------------------------------------------

//

//  Little Color Management System

//  Copyright (c) 1998-2020 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"

// Auxiliary: append a Lab identity after the given sequence of profiles

// and return the transform. Lab profile is closed, rest of profiles are kept open.

cmsHTRANSFORM _cmsChain2Lab(cmsContext            ContextID,

                            cmsUInt32Number        nProfiles,

                            cmsUInt32Number        InputFormat,

                            cmsUInt32Number        OutputFormat,

                            const cmsUInt32Number  Intents[],

                            const cmsHPROFILE      hProfiles[],

                            const cmsBool          BPC[],

                            const cmsFloat64Number AdaptationStates[],

                            cmsUInt32Number        dwFlags)

{

    cmsHTRANSFORM xform;

    cmsHPROFILE   hLab;

    cmsHPROFILE   ProfileList[256];

    cmsBool       BPCList[256];

    cmsFloat64Number AdaptationList[256];

    cmsUInt32Number IntentList[256];

    cmsUInt32Number i;

    // This is a rather big number and there is no need of dynamic memory

    // since we are adding a profile, 254 + 1 = 255 and this is the limit

    if (nProfiles > 254) return NULL;

    // The output space

    hLab = cmsCreateLab4Profile(ContextID, NULL);

    if (hLab == NULL) return NULL;

    // Create a copy of parameters

    for (i=0; i < nProfiles; i++) {

        ProfileList[i]    = hProfiles[i];

        BPCList[i]        = BPC[i];

        AdaptationList[i] = AdaptationStates[i];

        IntentList[i]     = Intents[i];

    }

    // Place Lab identity at chain's end.

    ProfileList[nProfiles]    = hLab;

    BPCList[nProfiles]        = 0;

    AdaptationList[nProfiles] = 1.0;

    IntentList[nProfiles]     = INTENT_RELATIVE_COLORIMETRIC;

    // Create the transform

    xform = cmsCreateExtendedTransform(ContextID, nProfiles + 1, ProfileList,

                                       BPCList,

                                       IntentList,

                                       AdaptationList,

                                       NULL, 0,

                                       InputFormat,

                                       OutputFormat,

                                       dwFlags);

    cmsCloseProfile(ContextID, hLab);

    return xform;

}

// Compute K -> L* relationship. Flags may include black point compensation. In this case,

// the relationship is assumed from the profile with BPC to a black point zero.

static

cmsToneCurve* ComputeKToLstar(cmsContext            ContextID,

                               cmsUInt32Number       nPoints,

                               cmsUInt32Number       nProfiles,

                               const cmsUInt32Number Intents[],

                               const cmsHPROFILE     hProfiles[],

                               const cmsBool         BPC[],

                               const cmsFloat64Number AdaptationStates[],

                               cmsUInt32Number dwFlags)

{

    cmsToneCurve* out = NULL;

    cmsUInt32Number i;

    cmsHTRANSFORM xform;

    cmsCIELab Lab;

    cmsFloat32Number cmyk[4];

    cmsFloat32Number* SampledPoints;

    xform = _cmsChain2Lab(ContextID, nProfiles, TYPE_CMYK_FLT, TYPE_Lab_DBL, Intents, hProfiles, BPC, AdaptationStates, dwFlags);

    if (xform == NULL) return NULL;

    SampledPoints = (cmsFloat32Number*) _cmsCalloc(ContextID, nPoints, sizeof(cmsFloat32Number));

    if (SampledPoints  == NULL) goto Error;

    for (i=0; i < nPoints; i++) {

        cmyk[0] = 0;

        cmyk[1] = 0;

        cmyk[2] = 0;

        cmyk[3] = (cmsFloat32Number) ((i * 100.0) / (nPoints-1));

        cmsDoTransform(ContextID, xform, cmyk, &Lab, 1);

        SampledPoints[i]= (cmsFloat32Number) (1.0 - Lab.L / 100.0); // Negate K for easier operation

    }

    out = cmsBuildTabulatedToneCurveFloat(ContextID, nPoints, SampledPoints);

Error:

    cmsDeleteTransform(ContextID, xform);

    if (SampledPoints) _cmsFree(ContextID, SampledPoints);

    return out;

}

// Compute Black tone curve on a CMYK -> CMYK transform. This is done by

// using the proof direction on both profiles to find K->L* relationship

// then joining both curves. dwFlags may include black point compensation.

cmsToneCurve* _cmsBuildKToneCurve(cmsContext        ContextID,

                                   cmsUInt32Number   nPoints,

                                   cmsUInt32Number   nProfiles,

                                   const cmsUInt32Number Intents[],

                                   const cmsHPROFILE hProfiles[],

                                   const cmsBool     BPC[],

                                   const cmsFloat64Number AdaptationStates[],

                                   cmsUInt32Number   dwFlags)

{

    cmsToneCurve *in, *out, *KTone;

    // Make sure CMYK -> CMYK

    if (cmsGetColorSpace(ContextID, hProfiles[0]) != cmsSigCmykData ||

        cmsGetColorSpace(ContextID, hProfiles[nProfiles-1])!= cmsSigCmykData) return NULL;

    // Make sure last is an output profile

    if (cmsGetDeviceClass(ContextID, hProfiles[nProfiles - 1]) != cmsSigOutputClass) return NULL;

    // Create individual curves. BPC works also as each K to L* is

    // computed as a BPC to zero black point in case of L*

    in  = ComputeKToLstar(ContextID, nPoints, nProfiles - 1, Intents, hProfiles, BPC, AdaptationStates, dwFlags);

    if (in == NULL) return NULL;

    out = ComputeKToLstar(ContextID, nPoints, 1,

                            Intents + (nProfiles - 1),

                            &hProfiles [nProfiles - 1],

                            BPC + (nProfiles - 1),

                            AdaptationStates + (nProfiles - 1),

                            dwFlags);

    if (out == NULL) {

        cmsFreeToneCurve(ContextID, in);

        return NULL;

    }

    // Build the relationship. This effectively limits the maximum accuracy to 16 bits, but

    // since this is used on black-preserving LUTs, we are not losing  accuracy in any case

    KTone = cmsJoinToneCurve(ContextID, in, out, nPoints);

    // Get rid of components

    cmsFreeToneCurve(ContextID, in); cmsFreeToneCurve(ContextID, out);

    // Something went wrong...

    if (KTone == NULL) return NULL;

    // Make sure it is monotonic

    if (!cmsIsToneCurveMonotonic(ContextID, KTone)) {

        cmsFreeToneCurve(ContextID, KTone);

        return NULL;

    }

    return KTone;

}

// Gamut LUT Creation -----------------------------------------------------------------------------------------

// Used by gamut & softproofing

typedef struct {

    cmsHTRANSFORM hInput;               // From whatever input color space. 16 bits to DBL

    cmsHTRANSFORM hForward, hReverse;   // Transforms going from Lab to colorant and back

    cmsFloat64Number Thereshold;        // The thereshold after which is considered out of gamut

    } GAMUTCHAIN;

// This sampler does compute gamut boundaries by comparing original

// values with a transform going back and forth. Values above ERR_THERESHOLD

// of maximum are considered out of gamut.

#define ERR_THERESHOLD      5

static

int GamutSampler(cmsContext ContextID, CMSREGISTER const cmsUInt16Number In[], CMSREGISTER cmsUInt16Number Out[], CMSREGISTER void* Cargo)

{

    GAMUTCHAIN*  t = (GAMUTCHAIN* ) Cargo;

    cmsCIELab LabIn1, LabOut1;

    cmsCIELab LabIn2, LabOut2;

    cmsUInt16Number Proof[cmsMAXCHANNELS], Proof2[cmsMAXCHANNELS];

    cmsFloat64Number dE1, dE2, ErrorRatio;

    // Assume in-gamut by default.

    ErrorRatio = 1.0;

    // Convert input to Lab

    cmsDoTransform(ContextID, t -> hInput, In, &LabIn1, 1);

    // converts from PCS to colorant. This always

    // does return in-gamut values,

    cmsDoTransform(ContextID, t -> hForward, &LabIn1, Proof, 1);

    // Now, do the inverse, from colorant to PCS.

    cmsDoTransform(ContextID, t -> hReverse, Proof, &LabOut1, 1);

    memmove(&LabIn2, &LabOut1, sizeof(cmsCIELab));

    // Try again, but this time taking Check as input

    cmsDoTransform(ContextID, t -> hForward, &LabOut1, Proof2, 1);

    cmsDoTransform(ContextID, t -> hReverse, Proof2, &LabOut2, 1);

    // Take difference of direct value

    dE1 = cmsDeltaE(ContextID, &LabIn1, &LabOut1);

    // Take difference of converted value

    dE2 = cmsDeltaE(ContextID, &LabIn2, &LabOut2);

    // if dE1 is small and dE2 is small, value is likely to be in gamut

    if (dE1 < t->Thereshold && dE2 < t->Thereshold)

        Out[0] = 0;

    else {

        // if dE1 is small and dE2 is big, undefined. Assume in gamut

        if (dE1 < t->Thereshold && dE2 > t->Thereshold)

            Out[0] = 0;

        else

            // dE1 is big and dE2 is small, clearly out of gamut

            if (dE1 > t->Thereshold && dE2 < t->Thereshold)

                Out[0] = (cmsUInt16Number) _cmsQuickFloor((dE1 - t->Thereshold) + .5);

            else  {

                // dE1 is big and dE2 is also big, could be due to perceptual mapping

                // so take error ratio

                if (dE2 == 0.0)

                    ErrorRatio = dE1;

                else

                    ErrorRatio = dE1 / dE2;

                if (ErrorRatio > t->Thereshold)

                    Out[0] = (cmsUInt16Number)  _cmsQuickFloor((ErrorRatio - t->Thereshold) + .5);

                else

                    Out[0] = 0;

            }

    }

    return TRUE;

}

// Does compute a gamut LUT going back and forth across pcs -> relativ. colorimetric intent -> pcs

// the dE obtained is then annotated on the LUT. Values truly out of gamut are clipped to dE = 0xFFFE

// and values changed are supposed to be handled by any gamut remapping, so, are out of gamut as well.

//

// **WARNING: This algorithm does assume that gamut remapping algorithms does NOT move in-gamut colors,

// of course, many perceptual and saturation intents does not work in such way, but relativ. ones should.

cmsPipeline* _cmsCreateGamutCheckPipeline(cmsContext ContextID,

                                          cmsHPROFILE hProfiles[],

                                          cmsBool  BPC[],

                                          cmsUInt32Number Intents[],

                                          cmsFloat64Number AdaptationStates[],

                                          cmsUInt32Number nGamutPCSposition,

                                          cmsHPROFILE hGamut)

{

    cmsHPROFILE hLab;

    cmsPipeline* Gamut;

    cmsStage* CLUT;

    cmsUInt32Number dwFormat;

    GAMUTCHAIN Chain;

    cmsUInt32Number nChannels, nGridpoints;

    cmsColorSpaceSignature ColorSpace;

    cmsUInt32Number i;

    cmsHPROFILE ProfileList[256];

    cmsBool     BPCList[256];

    cmsFloat64Number AdaptationList[256];

    cmsUInt32Number IntentList[256];

    memset(&Chain, 0, sizeof(GAMUTCHAIN));

    if (nGamutPCSposition <= 0 || nGamutPCSposition > 255) {

        cmsSignalError(ContextID, cmsERROR_RANGE, "Wrong position of PCS. 1..255 expected, %d found.", nGamutPCSposition);

        return NULL;

    }

    hLab = cmsCreateLab4Profile(ContextID, NULL);

    if (hLab == NULL) return NULL;

    // The figure of merit. On matrix-shaper profiles, should be almost zero as

    // the conversion is pretty exact. On LUT based profiles, different resolutions

    // of input and output CLUT may result in differences.

    if (cmsIsMatrixShaper(ContextID, hGamut)) {

        Chain.Thereshold = 1.0;

    }

    else {

        Chain.Thereshold = ERR_THERESHOLD;

    }

    // Create a copy of parameters

    for (i=0; i < nGamutPCSposition; i++) {

        ProfileList[i]    = hProfiles[i];

        BPCList[i]        = BPC[i];

        AdaptationList[i] = AdaptationStates[i];

        IntentList[i]     = Intents[i];

    }

    // Fill Lab identity

    ProfileList[nGamutPCSposition] = hLab;

    BPCList[nGamutPCSposition] = 0;

    AdaptationList[nGamutPCSposition] = 1.0;

    IntentList[nGamutPCSposition] = INTENT_RELATIVE_COLORIMETRIC;

    ColorSpace  = cmsGetColorSpace(ContextID, hGamut);

    nChannels   = cmsChannelsOf(ContextID, ColorSpace);

    nGridpoints = _cmsReasonableGridpointsByColorspace(ContextID, ColorSpace, cmsFLAGS_HIGHRESPRECALC);

    dwFormat    = (CHANNELS_SH(nChannels)|BYTES_SH(2));

    // 16 bits to Lab double

    Chain.hInput = cmsCreateExtendedTransform(ContextID,

        nGamutPCSposition + 1,

        ProfileList,

        BPCList,

        IntentList,

        AdaptationList,

        NULL, 0,

        dwFormat, TYPE_Lab_DBL,

        cmsFLAGS_NOCACHE);

    // Does create the forward step. Lab double to device

    dwFormat    = (CHANNELS_SH(nChannels)|BYTES_SH(2));

    Chain.hForward = cmsCreateTransform(ContextID,

        hLab, TYPE_Lab_DBL,

        hGamut, dwFormat,

        INTENT_RELATIVE_COLORIMETRIC,

        cmsFLAGS_NOCACHE);

    // Does create the backwards step

    Chain.hReverse = cmsCreateTransform(ContextID, hGamut, dwFormat,

        hLab, TYPE_Lab_DBL,

        INTENT_RELATIVE_COLORIMETRIC,

        cmsFLAGS_NOCACHE);

    // All ok?

    if (Chain.hInput && Chain.hForward && Chain.hReverse) {

        // Go on, try to compute gamut LUT from PCS. This consist on a single channel containing

        // dE when doing a transform back and forth on the colorimetric intent.

        Gamut = cmsPipelineAlloc(ContextID, 3, 1);

        if (Gamut != NULL) {

            CLUT = cmsStageAllocCLut16bit(ContextID, nGridpoints, nChannels, 1, NULL);

            if (!cmsPipelineInsertStage(ContextID, Gamut, cmsAT_BEGIN, CLUT)) {

                cmsPipelineFree(ContextID, Gamut);

                Gamut = NULL;

            }

            else {

                cmsStageSampleCLut16bit(ContextID, CLUT, GamutSampler, (void*) &Chain, 0);

            }

        }

    }

    else

        Gamut = NULL;   // Didn't work...

    // Free all needed stuff.

    if (Chain.hInput)   cmsDeleteTransform(ContextID, Chain.hInput);

    if (Chain.hForward) cmsDeleteTransform(ContextID, Chain.hForward);

    if (Chain.hReverse) cmsDeleteTransform(ContextID, Chain.hReverse);

    if (hLab) cmsCloseProfile(ContextID, hLab);

    // And return computed hull

    return Gamut;

}

// Total Area Coverage estimation ----------------------------------------------------------------

typedef struct {

    cmsUInt32Number  nOutputChans;

    cmsHTRANSFORM    hRoundTrip;

    cmsFloat32Number MaxTAC;

    cmsFloat32Number MaxInput[cmsMAXCHANNELS];

} cmsTACestimator;

// This callback just accounts the maximum ink dropped in the given node. It does not populate any

// memory, as the destination table is NULL. Its only purpose it to know the global maximum.

static

int EstimateTAC(cmsContext ContextID, CMSREGISTER const cmsUInt16Number In[], CMSREGISTER cmsUInt16Number Out[], CMSREGISTER void * Cargo)

{

    cmsTACestimator* bp = (cmsTACestimator*) Cargo;

    cmsFloat32Number RoundTrip[cmsMAXCHANNELS];

    cmsUInt32Number i;

    cmsFloat32Number Sum;

    // Evaluate the xform

    cmsDoTransform(ContextID, bp->hRoundTrip, In, RoundTrip, 1);

    // All all amounts of ink

    for (Sum=0, i=0; i < bp ->nOutputChans; i++)

            Sum += RoundTrip[i];

    // If above maximum, keep track of input values

    if (Sum > bp ->MaxTAC) {

            bp ->MaxTAC = Sum;

            for (i=0; i < bp ->nOutputChans; i++) {

                bp ->MaxInput[i] = In[i];

            }

    }

    return TRUE;

    cmsUNUSED_PARAMETER(Out);

}

// Detect Total area coverage of the profile

cmsFloat64Number CMSEXPORT cmsDetectTAC(cmsContext ContextID, cmsHPROFILE hProfile)

{

    cmsTACestimator bp;

    cmsUInt32Number dwFormatter;

    cmsUInt32Number GridPoints[MAX_INPUT_DIMENSIONS];

    cmsHPROFILE hLab;

    // TAC only works on output profiles

    if (cmsGetDeviceClass(ContextID, hProfile) != cmsSigOutputClass) {

        return 0;

    }

    // Create a fake formatter for result

    dwFormatter = cmsFormatterForColorspaceOfProfile(ContextID, hProfile, 4, TRUE);

    bp.nOutputChans = T_CHANNELS(dwFormatter);

    bp.MaxTAC = 0;    // Initial TAC is 0

    //  for safety

    if (bp.nOutputChans >= cmsMAXCHANNELS) return 0;

    hLab = cmsCreateLab4Profile(ContextID, NULL);

    if (hLab == NULL) return 0;

    // Setup a roundtrip on perceptual intent in output profile for TAC estimation

    bp.hRoundTrip = cmsCreateTransform(ContextID, hLab, TYPE_Lab_16,

                                          hProfile, dwFormatter, INTENT_PERCEPTUAL, cmsFLAGS_NOOPTIMIZE|cmsFLAGS_NOCACHE);

    cmsCloseProfile(ContextID, hLab);

    if (bp.hRoundTrip == NULL) return 0;

    // For L* we only need black and white. For C* we need many points

    GridPoints[0] = 6;

    GridPoints[1] = 74;

    GridPoints[2] = 74;

    if (!cmsSliceSpace16(ContextID, 3, GridPoints, EstimateTAC, &bp)) {

        bp.MaxTAC = 0;

    }

    cmsDeleteTransform(ContextID, bp.hRoundTrip);

    // Results in %

    return bp.MaxTAC;

}

// Carefully,  clamp on CIELab space.

cmsBool CMSEXPORT cmsDesaturateLab(cmsContext ContextID, cmsCIELab* Lab,

                                   double amax, double amin,

                                   double bmax, double bmin)

{

    // Whole Luma surface to zero

    if (Lab -> L < 0) {

        Lab-> L = Lab->a = Lab-> b = 0.0;

        return FALSE;

    }

    // Clamp white, DISCARD HIGHLIGHTS. This is done

    // in such way because icc spec doesn't allow the

    // use of L>100 as a highlight means.

    if (Lab->L > 100)

        Lab -> L = 100;

    // Check out gamut prism, on a, b faces

    if (Lab -> a < amin || Lab->a > amax||

        Lab -> b < bmin || Lab->b > bmax) {

            cmsCIELCh LCh;

            double h, slope;

            // Falls outside a, b limits. Transports to LCh space,

            // and then do the clipping

            if (Lab -> a == 0.0) { // Is hue exactly 90?

                // atan will not work, so clamp here

                Lab -> b = Lab->b < 0 ? bmin : bmax;

                return TRUE;

            }

            cmsLab2LCh(ContextID, &LCh, Lab);

            slope = Lab -> b / Lab -> a;

            h = LCh.h;

            // There are 4 zones

            if ((h >= 0. && h < 45.) ||

                (h >= 315 && h <= 360.)) {

                    // clip by amax

                    Lab -> a = amax;

                    Lab -> b = amax * slope;

            }

            else

                if (h >= 45. && h < 135.)

                {

                    // clip by bmax

                    Lab -> b = bmax;

                    Lab -> a = bmax / slope;

                }

                else

                    if (h >= 135. && h < 225.) {

                        // clip by amin

                        Lab -> a = amin;

                        Lab -> b = amin * slope;

                    }

                    else

                        if (h >= 225. && h < 315.) {

                            // clip by bmin

                            Lab -> b = bmin;

                            Lab -> a = bmin / slope;

                        }

                        else  {

                            cmsSignalError(0, cmsERROR_RANGE, "Invalid angle");

                            return FALSE;

                        }

    }

    return TRUE;

}

// Detect whatever a given ICC profile works in linear (gamma 1.0) space

// Actually, doing that "well" is quite hard, since every component may behave completely different.

// Since the true point of this function is to detect suitable optimizations, I am imposing some requirements

// that simplifies things: only RGB, and only profiles that can got in both directions.

// The algorith obtains Y from a syntetical gray R=G=B. Then least squares fitting is used to estimate gamma.

// For gamma close to 1.0, RGB is linear. On profiles not supported, -1 is returned.

cmsFloat64Number CMSEXPORT cmsDetectRGBProfileGamma(cmsContext ContextID, cmsHPROFILE hProfile, cmsFloat64Number thereshold)

{

    cmsHPROFILE hXYZ;

    cmsHTRANSFORM xform;

    cmsToneCurve* Y_curve;

    cmsUInt16Number rgb[256][3];

    cmsCIEXYZ XYZ[256];

    cmsFloat32Number Y_normalized[256];

    cmsFloat64Number gamma;

    cmsProfileClassSignature cl;

    int i;

    if (cmsGetColorSpace(ContextID, hProfile) != cmsSigRgbData)

        return -1;

    cl = cmsGetDeviceClass(ContextID, hProfile);

    if (cl != cmsSigInputClass && cl != cmsSigDisplayClass &&

        cl != cmsSigOutputClass && cl != cmsSigColorSpaceClass)

        return -1;

    hXYZ = cmsCreateXYZProfile(ContextID);

    xform = cmsCreateTransform(ContextID, hProfile, TYPE_RGB_16, hXYZ, TYPE_XYZ_DBL,

                                    INTENT_RELATIVE_COLORIMETRIC, cmsFLAGS_NOOPTIMIZE);

    if (xform == NULL) { // If not RGB or forward direction is not supported, regret with the previous error

        cmsCloseProfile(ContextID, hXYZ);

        return -1;

    }

    for (i = 0; i < 256; i++) {

        rgb[i][0] = rgb[i][1] = rgb[i][2] = FROM_8_TO_16(i);

    }

    cmsDoTransform(ContextID, xform, rgb, XYZ, 256);

    cmsDeleteTransform(ContextID, xform);

    cmsCloseProfile(ContextID, hXYZ);

    for (i = 0; i < 256; i++) {

        Y_normalized[i] = (cmsFloat32Number) XYZ[i].Y;

    }

    Y_curve = cmsBuildTabulatedToneCurveFloat(ContextID, 256, Y_normalized);

    if (Y_curve == NULL)

        return -1;

    gamma = cmsEstimateGamma(ContextID, Y_curve, thereshold);

    cmsFreeToneCurve(ContextID, Y_curve);

    return gamma;

}