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Diffstat (limited to 'chromium/third_party/pdfium/third_party/lcms/src/cmssamp.c')
| -rw-r--r-- | chromium/third_party/pdfium/third_party/lcms/src/cmssamp.c | 547 |
1 files changed, 547 insertions, 0 deletions
diff --git a/chromium/third_party/pdfium/third_party/lcms/src/cmssamp.c b/chromium/third_party/pdfium/third_party/lcms/src/cmssamp.c new file mode 100644 index 00000000000..a9997fa8eec --- /dev/null +++ b/chromium/third_party/pdfium/third_party/lcms/src/cmssamp.c @@ -0,0 +1,547 @@ +//--------------------------------------------------------------------------------- +// +// Little Color Management System +// Copyright (c) 1998-2016 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" + + +#define cmsmin(a, b) (((a) < (b)) ? (a) : (b)) +#define cmsmax(a, b) (((a) > (b)) ? (a) : (b)) + +// This file contains routines for resampling and LUT optimization, black point detection +// and black preservation. + +// Black point detection ------------------------------------------------------------------------- + + +// PCS -> PCS round trip transform, always uses relative intent on the device -> pcs +static +cmsHTRANSFORM CreateRoundtripXForm(cmsHPROFILE hProfile, cmsUInt32Number nIntent) +{ + cmsContext ContextID = cmsGetProfileContextID(hProfile); + cmsHPROFILE hLab = cmsCreateLab4ProfileTHR(ContextID, NULL); + cmsHTRANSFORM xform; + cmsBool BPC[4] = { FALSE, FALSE, FALSE, FALSE }; + cmsFloat64Number States[4] = { 1.0, 1.0, 1.0, 1.0 }; + cmsHPROFILE hProfiles[4]; + cmsUInt32Number Intents[4]; + + hProfiles[0] = hLab; hProfiles[1] = hProfile; hProfiles[2] = hProfile; hProfiles[3] = hLab; + Intents[0] = INTENT_RELATIVE_COLORIMETRIC; Intents[1] = nIntent; Intents[2] = INTENT_RELATIVE_COLORIMETRIC; Intents[3] = INTENT_RELATIVE_COLORIMETRIC; + + xform = cmsCreateExtendedTransform(ContextID, 4, hProfiles, BPC, Intents, + States, NULL, 0, TYPE_Lab_DBL, TYPE_Lab_DBL, cmsFLAGS_NOCACHE|cmsFLAGS_NOOPTIMIZE); + + cmsCloseProfile(hLab); + return xform; +} + +// Use darker colorants to obtain black point. This works in the relative colorimetric intent and +// assumes more ink results in darker colors. No ink limit is assumed. +static +cmsBool BlackPointAsDarkerColorant(cmsHPROFILE hInput, + cmsUInt32Number Intent, + cmsCIEXYZ* BlackPoint, + cmsUInt32Number dwFlags) +{ + cmsUInt16Number *Black; + cmsHTRANSFORM xform; + cmsColorSpaceSignature Space; + cmsUInt32Number nChannels; + cmsUInt32Number dwFormat; + cmsHPROFILE hLab; + cmsCIELab Lab; + cmsCIEXYZ BlackXYZ; + cmsContext ContextID = cmsGetProfileContextID(hInput); + + // If the profile does not support input direction, assume Black point 0 + if (!cmsIsIntentSupported(hInput, Intent, LCMS_USED_AS_INPUT)) { + + BlackPoint -> X = BlackPoint ->Y = BlackPoint -> Z = 0.0; + return FALSE; + } + + // Create a formatter which has n channels and floating point + dwFormat = cmsFormatterForColorspaceOfProfile(hInput, 2, FALSE); + + // Try to get black by using black colorant + Space = cmsGetColorSpace(hInput); + + // This function returns darker colorant in 16 bits for several spaces + if (!_cmsEndPointsBySpace(Space, NULL, &Black, &nChannels)) { + + BlackPoint -> X = BlackPoint ->Y = BlackPoint -> Z = 0.0; + return FALSE; + } + + if (nChannels != T_CHANNELS(dwFormat)) { + BlackPoint -> X = BlackPoint ->Y = BlackPoint -> Z = 0.0; + return FALSE; + } + + // Lab will be used as the output space, but lab2 will avoid recursion + hLab = cmsCreateLab2ProfileTHR(ContextID, NULL); + if (hLab == NULL) { + BlackPoint -> X = BlackPoint ->Y = BlackPoint -> Z = 0.0; + return FALSE; + } + + // Create the transform + xform = cmsCreateTransformTHR(ContextID, hInput, dwFormat, + hLab, TYPE_Lab_DBL, Intent, cmsFLAGS_NOOPTIMIZE|cmsFLAGS_NOCACHE); + cmsCloseProfile(hLab); + + if (xform == NULL) { + + // Something went wrong. Get rid of open resources and return zero as black + BlackPoint -> X = BlackPoint ->Y = BlackPoint -> Z = 0.0; + return FALSE; + } + + // Convert black to Lab + cmsDoTransform(xform, Black, &Lab, 1); + + // Force it to be neutral, clip to max. L* of 50 + Lab.a = Lab.b = 0; + if (Lab.L > 50) Lab.L = 50; + + // Free the resources + cmsDeleteTransform(xform); + + // Convert from Lab (which is now clipped) to XYZ. + cmsLab2XYZ(NULL, &BlackXYZ, &Lab); + + if (BlackPoint != NULL) + *BlackPoint = BlackXYZ; + + return TRUE; + + cmsUNUSED_PARAMETER(dwFlags); +} + +// Get a black point of output CMYK profile, discounting any ink-limiting embedded +// in the profile. For doing that, we use perceptual intent in input direction: +// Lab (0, 0, 0) -> [Perceptual] Profile -> CMYK -> [Rel. colorimetric] Profile -> Lab +static +cmsBool BlackPointUsingPerceptualBlack(cmsCIEXYZ* BlackPoint, cmsHPROFILE hProfile) +{ + cmsHTRANSFORM hRoundTrip; + cmsCIELab LabIn, LabOut; + cmsCIEXYZ BlackXYZ; + + // Is the intent supported by the profile? + if (!cmsIsIntentSupported(hProfile, INTENT_PERCEPTUAL, LCMS_USED_AS_INPUT)) { + + BlackPoint -> X = BlackPoint ->Y = BlackPoint -> Z = 0.0; + return TRUE; + } + + hRoundTrip = CreateRoundtripXForm(hProfile, INTENT_PERCEPTUAL); + if (hRoundTrip == NULL) { + BlackPoint -> X = BlackPoint ->Y = BlackPoint -> Z = 0.0; + return FALSE; + } + + LabIn.L = LabIn.a = LabIn.b = 0; + cmsDoTransform(hRoundTrip, &LabIn, &LabOut, 1); + + // Clip Lab to reasonable limits + if (LabOut.L > 50) LabOut.L = 50; + LabOut.a = LabOut.b = 0; + + cmsDeleteTransform(hRoundTrip); + + // Convert it to XYZ + cmsLab2XYZ(NULL, &BlackXYZ, &LabOut); + + if (BlackPoint != NULL) + *BlackPoint = BlackXYZ; + + return TRUE; +} + +// This function shouldn't exist at all -- there is such quantity of broken +// profiles on black point tag, that we must somehow fix chromaticity to +// avoid huge tint when doing Black point compensation. This function does +// just that. There is a special flag for using black point tag, but turned +// off by default because it is bogus on most profiles. The detection algorithm +// involves to turn BP to neutral and to use only L component. +cmsBool CMSEXPORT cmsDetectBlackPoint(cmsCIEXYZ* BlackPoint, cmsHPROFILE hProfile, cmsUInt32Number Intent, cmsUInt32Number dwFlags) +{ + cmsProfileClassSignature devClass; + + // Make sure the device class is adequate + devClass = cmsGetDeviceClass(hProfile); + if (devClass == cmsSigLinkClass || + devClass == cmsSigAbstractClass || + devClass == cmsSigNamedColorClass) { + BlackPoint -> X = BlackPoint ->Y = BlackPoint -> Z = 0.0; + return FALSE; + } + + // Make sure intent is adequate + if (Intent != INTENT_PERCEPTUAL && + Intent != INTENT_RELATIVE_COLORIMETRIC && + Intent != INTENT_SATURATION) { + BlackPoint -> X = BlackPoint ->Y = BlackPoint -> Z = 0.0; + return FALSE; + } + + // v4 + perceptual & saturation intents does have its own black point, and it is + // well specified enough to use it. Black point tag is deprecated in V4. + if ((cmsGetEncodedICCversion(hProfile) >= 0x4000000) && + (Intent == INTENT_PERCEPTUAL || Intent == INTENT_SATURATION)) { + + // Matrix shaper share MRC & perceptual intents + if (cmsIsMatrixShaper(hProfile)) + return BlackPointAsDarkerColorant(hProfile, INTENT_RELATIVE_COLORIMETRIC, BlackPoint, 0); + + // Get Perceptual black out of v4 profiles. That is fixed for perceptual & saturation intents + BlackPoint -> X = cmsPERCEPTUAL_BLACK_X; + BlackPoint -> Y = cmsPERCEPTUAL_BLACK_Y; + BlackPoint -> Z = cmsPERCEPTUAL_BLACK_Z; + + return TRUE; + } + + +#ifdef CMS_USE_PROFILE_BLACK_POINT_TAG + + // v2, v4 rel/abs colorimetric + if (cmsIsTag(hProfile, cmsSigMediaBlackPointTag) && + Intent == INTENT_RELATIVE_COLORIMETRIC) { + + cmsCIEXYZ *BlackPtr, BlackXYZ, UntrustedBlackPoint, TrustedBlackPoint, MediaWhite; + cmsCIELab Lab; + + // If black point is specified, then use it, + + BlackPtr = cmsReadTag(hProfile, cmsSigMediaBlackPointTag); + if (BlackPtr != NULL) { + + BlackXYZ = *BlackPtr; + _cmsReadMediaWhitePoint(&MediaWhite, hProfile); + + // Black point is absolute XYZ, so adapt to D50 to get PCS value + cmsAdaptToIlluminant(&UntrustedBlackPoint, &MediaWhite, cmsD50_XYZ(), &BlackXYZ); + + // Force a=b=0 to get rid of any chroma + cmsXYZ2Lab(NULL, &Lab, &UntrustedBlackPoint); + Lab.a = Lab.b = 0; + if (Lab.L > 50) Lab.L = 50; // Clip to L* <= 50 + cmsLab2XYZ(NULL, &TrustedBlackPoint, &Lab); + + if (BlackPoint != NULL) + *BlackPoint = TrustedBlackPoint; + + return TRUE; + } + } +#endif + + // That is about v2 profiles. + + // If output profile, discount ink-limiting and that's all + if (Intent == INTENT_RELATIVE_COLORIMETRIC && + (cmsGetDeviceClass(hProfile) == cmsSigOutputClass) && + (cmsGetColorSpace(hProfile) == cmsSigCmykData)) + return BlackPointUsingPerceptualBlack(BlackPoint, hProfile); + + // Nope, compute BP using current intent. + return BlackPointAsDarkerColorant(hProfile, Intent, BlackPoint, dwFlags); +} + + + +// --------------------------------------------------------------------------------------------------------- + +// Least Squares Fit of a Quadratic Curve to Data +// http://www.personal.psu.edu/jhm/f90/lectures/lsq2.html + +static +cmsFloat64Number RootOfLeastSquaresFitQuadraticCurve(int n, cmsFloat64Number x[], cmsFloat64Number y[]) +{ + double sum_x = 0, sum_x2 = 0, sum_x3 = 0, sum_x4 = 0; + double sum_y = 0, sum_yx = 0, sum_yx2 = 0; + double d, a, b, c; + int i; + cmsMAT3 m; + cmsVEC3 v, res; + + if (n < 4) return 0; + + for (i=0; i < n; i++) { + + double xn = x[i]; + double yn = y[i]; + + sum_x += xn; + sum_x2 += xn*xn; + sum_x3 += xn*xn*xn; + sum_x4 += xn*xn*xn*xn; + + sum_y += yn; + sum_yx += yn*xn; + sum_yx2 += yn*xn*xn; + } + + _cmsVEC3init(&m.v[0], n, sum_x, sum_x2); + _cmsVEC3init(&m.v[1], sum_x, sum_x2, sum_x3); + _cmsVEC3init(&m.v[2], sum_x2, sum_x3, sum_x4); + + _cmsVEC3init(&v, sum_y, sum_yx, sum_yx2); + + if (!_cmsMAT3solve(&res, &m, &v)) return 0; + + + a = res.n[2]; + b = res.n[1]; + c = res.n[0]; + + if (fabs(a) < 1.0E-10) { + + return cmsmin(0, cmsmax(50, -c/b )); + } + else { + + d = b*b - 4.0 * a * c; + if (d <= 0) { + return 0; + } + else { + + double rt = (-b + sqrt(d)) / (2.0 * a); + + return cmsmax(0, cmsmin(50, rt)); + } + } + +} + + + +// Calculates the black point of a destination profile. +// This algorithm comes from the Adobe paper disclosing its black point compensation method. +cmsBool CMSEXPORT cmsDetectDestinationBlackPoint(cmsCIEXYZ* BlackPoint, cmsHPROFILE hProfile, cmsUInt32Number Intent, cmsUInt32Number dwFlags) +{ + cmsColorSpaceSignature ColorSpace; + cmsHTRANSFORM hRoundTrip = NULL; + cmsCIELab InitialLab, destLab, Lab; + cmsFloat64Number inRamp[256], outRamp[256]; + cmsFloat64Number MinL, MaxL; + cmsBool NearlyStraightMidrange = TRUE; + cmsFloat64Number yRamp[256]; + cmsFloat64Number x[256], y[256]; + cmsFloat64Number lo, hi; + int n, l; + cmsProfileClassSignature devClass; + + // Make sure the device class is adequate + devClass = cmsGetDeviceClass(hProfile); + if (devClass == cmsSigLinkClass || + devClass == cmsSigAbstractClass || + devClass == cmsSigNamedColorClass) { + BlackPoint -> X = BlackPoint ->Y = BlackPoint -> Z = 0.0; + return FALSE; + } + + // Make sure intent is adequate + if (Intent != INTENT_PERCEPTUAL && + Intent != INTENT_RELATIVE_COLORIMETRIC && + Intent != INTENT_SATURATION) { + BlackPoint -> X = BlackPoint ->Y = BlackPoint -> Z = 0.0; + return FALSE; + } + + + // v4 + perceptual & saturation intents does have its own black point, and it is + // well specified enough to use it. Black point tag is deprecated in V4. + if ((cmsGetEncodedICCversion(hProfile) >= 0x4000000) && + (Intent == INTENT_PERCEPTUAL || Intent == INTENT_SATURATION)) { + + // Matrix shaper share MRC & perceptual intents + if (cmsIsMatrixShaper(hProfile)) + return BlackPointAsDarkerColorant(hProfile, INTENT_RELATIVE_COLORIMETRIC, BlackPoint, 0); + + // Get Perceptual black out of v4 profiles. That is fixed for perceptual & saturation intents + BlackPoint -> X = cmsPERCEPTUAL_BLACK_X; + BlackPoint -> Y = cmsPERCEPTUAL_BLACK_Y; + BlackPoint -> Z = cmsPERCEPTUAL_BLACK_Z; + return TRUE; + } + + + // Check if the profile is lut based and gray, rgb or cmyk (7.2 in Adobe's document) + ColorSpace = cmsGetColorSpace(hProfile); + if (!cmsIsCLUT(hProfile, Intent, LCMS_USED_AS_OUTPUT ) || + (ColorSpace != cmsSigGrayData && + ColorSpace != cmsSigRgbData && + ColorSpace != cmsSigCmykData)) { + + // In this case, handle as input case + return cmsDetectBlackPoint(BlackPoint, hProfile, Intent, dwFlags); + } + + // It is one of the valid cases!, use Adobe algorithm + + + // Set a first guess, that should work on good profiles. + if (Intent == INTENT_RELATIVE_COLORIMETRIC) { + + cmsCIEXYZ IniXYZ; + + // calculate initial Lab as source black point + if (!cmsDetectBlackPoint(&IniXYZ, hProfile, Intent, dwFlags)) { + return FALSE; + } + + // convert the XYZ to lab + cmsXYZ2Lab(NULL, &InitialLab, &IniXYZ); + + } else { + + // set the initial Lab to zero, that should be the black point for perceptual and saturation + InitialLab.L = 0; + InitialLab.a = 0; + InitialLab.b = 0; + } + + + // Step 2 + // ====== + + // Create a roundtrip. Define a Transform BT for all x in L*a*b* + hRoundTrip = CreateRoundtripXForm(hProfile, Intent); + if (hRoundTrip == NULL) return FALSE; + + // Compute ramps + + for (l=0; l < 256; l++) { + + Lab.L = (cmsFloat64Number) (l * 100.0) / 255.0; + Lab.a = cmsmin(50, cmsmax(-50, InitialLab.a)); + Lab.b = cmsmin(50, cmsmax(-50, InitialLab.b)); + + cmsDoTransform(hRoundTrip, &Lab, &destLab, 1); + + inRamp[l] = Lab.L; + outRamp[l] = destLab.L; + } + + // Make monotonic + for (l = 254; l > 0; --l) { + outRamp[l] = cmsmin(outRamp[l], outRamp[l+1]); + } + + // Check + if (! (outRamp[0] < outRamp[255])) { + + cmsDeleteTransform(hRoundTrip); + BlackPoint -> X = BlackPoint ->Y = BlackPoint -> Z = 0.0; + return FALSE; + } + + + // Test for mid range straight (only on relative colorimetric) + NearlyStraightMidrange = TRUE; + MinL = outRamp[0]; MaxL = outRamp[255]; + if (Intent == INTENT_RELATIVE_COLORIMETRIC) { + + for (l=0; l < 256; l++) { + + if (! ((inRamp[l] <= MinL + 0.2 * (MaxL - MinL) ) || + (fabs(inRamp[l] - outRamp[l]) < 4.0 ))) + NearlyStraightMidrange = FALSE; + } + + // If the mid range is straight (as determined above) then the + // DestinationBlackPoint shall be the same as initialLab. + // Otherwise, the DestinationBlackPoint shall be determined + // using curve fitting. + if (NearlyStraightMidrange) { + + cmsLab2XYZ(NULL, BlackPoint, &InitialLab); + cmsDeleteTransform(hRoundTrip); + return TRUE; + } + } + + + // curve fitting: The round-trip curve normally looks like a nearly constant section at the black point, + // with a corner and a nearly straight line to the white point. + for (l=0; l < 256; l++) { + + yRamp[l] = (outRamp[l] - MinL) / (MaxL - MinL); + } + + // find the black point using the least squares error quadratic curve fitting + if (Intent == INTENT_RELATIVE_COLORIMETRIC) { + lo = 0.1; + hi = 0.5; + } + else { + + // Perceptual and saturation + lo = 0.03; + hi = 0.25; + } + + // Capture shadow points for the fitting. + n = 0; + for (l=0; l < 256; l++) { + + cmsFloat64Number ff = yRamp[l]; + + if (ff >= lo && ff < hi) { + x[n] = inRamp[l]; + y[n] = yRamp[l]; + n++; + } + } + + + // No suitable points + if (n < 3 ) { + cmsDeleteTransform(hRoundTrip); + BlackPoint -> X = BlackPoint ->Y = BlackPoint -> Z = 0.0; + return FALSE; + } + + + // fit and get the vertex of quadratic curve + Lab.L = RootOfLeastSquaresFitQuadraticCurve(n, x, y); + + if (Lab.L < 0.0) { // clip to zero L* if the vertex is negative + Lab.L = 0; + } + + Lab.a = InitialLab.a; + Lab.b = InitialLab.b; + + cmsLab2XYZ(NULL, BlackPoint, &Lab); + + cmsDeleteTransform(hRoundTrip); + return TRUE; +} |