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|
//---------------------------------------------------------------------------------
//
// Little Color Management System
// Copyright (c) 1998-2022 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"
// inter PCS conversions XYZ <-> CIE L* a* b*
/*
CIE 15:2004 CIELab is defined as:
L* = 116*f(Y/Yn) - 16 0 <= L* <= 100
a* = 500*[f(X/Xn) - f(Y/Yn)]
b* = 200*[f(Y/Yn) - f(Z/Zn)]
and
f(t) = t^(1/3) 1 >= t > (24/116)^3
(841/108)*t + (16/116) 0 <= t <= (24/116)^3
Reverse transform is:
X = Xn*[a* / 500 + (L* + 16) / 116] ^ 3 if (X/Xn) > (24/116)
= Xn*(a* / 500 + L* / 116) / 7.787 if (X/Xn) <= (24/116)
PCS in Lab2 is encoded as:
8 bit Lab PCS:
L* 0..100 into a 0..ff byte.
a* t + 128 range is -128.0 +127.0
b*
16 bit Lab PCS:
L* 0..100 into a 0..ff00 word.
a* t + 128 range is -128.0 +127.9961
b*
Interchange Space Component Actual Range Encoded Range
CIE XYZ X 0 -> 1.99997 0x0000 -> 0xffff
CIE XYZ Y 0 -> 1.99997 0x0000 -> 0xffff
CIE XYZ Z 0 -> 1.99997 0x0000 -> 0xffff
Version 2,3
-----------
CIELAB (16 bit) L* 0 -> 100.0 0x0000 -> 0xff00
CIELAB (16 bit) a* -128.0 -> +127.996 0x0000 -> 0x8000 -> 0xffff
CIELAB (16 bit) b* -128.0 -> +127.996 0x0000 -> 0x8000 -> 0xffff
Version 4
---------
CIELAB (16 bit) L* 0 -> 100.0 0x0000 -> 0xffff
CIELAB (16 bit) a* -128.0 -> +127 0x0000 -> 0x8080 -> 0xffff
CIELAB (16 bit) b* -128.0 -> +127 0x0000 -> 0x8080 -> 0xffff
*/
// Conversions
void CMSEXPORT cmsXYZ2xyY(cmsCIExyY* Dest, const cmsCIEXYZ* Source)
{
cmsFloat64Number ISum;
ISum = 1./(Source -> X + Source -> Y + Source -> Z);
Dest -> x = (Source -> X) * ISum;
Dest -> y = (Source -> Y) * ISum;
Dest -> Y = Source -> Y;
}
void CMSEXPORT cmsxyY2XYZ(cmsCIEXYZ* Dest, const cmsCIExyY* Source)
{
Dest -> X = (Source -> x / Source -> y) * Source -> Y;
Dest -> Y = Source -> Y;
Dest -> Z = ((1 - Source -> x - Source -> y) / Source -> y) * Source -> Y;
}
/*
The break point (24/116)^3 = (6/29)^3 is a very small amount of tristimulus
primary (0.008856). Generally, this only happens for
nearly ideal blacks and for some orange / amber colors in transmission mode.
For example, the Z value of the orange turn indicator lamp lens on an
automobile will often be below this value. But the Z does not
contribute to the perceived color directly.
*/
static
cmsFloat64Number f(cmsFloat64Number t)
{
const cmsFloat64Number Limit = (24.0/116.0) * (24.0/116.0) * (24.0/116.0);
if (t <= Limit)
return (841.0/108.0) * t + (16.0/116.0);
else
return pow(t, 1.0/3.0);
}
static
cmsFloat64Number f_1(cmsFloat64Number t)
{
const cmsFloat64Number Limit = (24.0/116.0);
if (t <= Limit) {
return (108.0/841.0) * (t - (16.0/116.0));
}
return t * t * t;
}
// Standard XYZ to Lab. it can handle negative XZY numbers in some cases
void CMSEXPORT cmsXYZ2Lab(const cmsCIEXYZ* WhitePoint, cmsCIELab* Lab, const cmsCIEXYZ* xyz)
{
cmsFloat64Number fx, fy, fz;
if (WhitePoint == NULL)
WhitePoint = cmsD50_XYZ();
fx = f(xyz->X / WhitePoint->X);
fy = f(xyz->Y / WhitePoint->Y);
fz = f(xyz->Z / WhitePoint->Z);
Lab->L = 116.0*fy - 16.0;
Lab->a = 500.0*(fx - fy);
Lab->b = 200.0*(fy - fz);
}
// Standard XYZ to Lab. It can return negative XYZ in some cases
void CMSEXPORT cmsLab2XYZ(const cmsCIEXYZ* WhitePoint, cmsCIEXYZ* xyz, const cmsCIELab* Lab)
{
cmsFloat64Number x, y, z;
if (WhitePoint == NULL)
WhitePoint = cmsD50_XYZ();
y = (Lab-> L + 16.0) / 116.0;
x = y + 0.002 * Lab -> a;
z = y - 0.005 * Lab -> b;
xyz -> X = f_1(x) * WhitePoint -> X;
xyz -> Y = f_1(y) * WhitePoint -> Y;
xyz -> Z = f_1(z) * WhitePoint -> Z;
}
static
cmsFloat64Number L2float2(cmsUInt16Number v)
{
return (cmsFloat64Number) v / 652.800;
}
// the a/b part
static
cmsFloat64Number ab2float2(cmsUInt16Number v)
{
return ((cmsFloat64Number) v / 256.0) - 128.0;
}
static
cmsUInt16Number L2Fix2(cmsFloat64Number L)
{
return _cmsQuickSaturateWord(L * 652.8);
}
static
cmsUInt16Number ab2Fix2(cmsFloat64Number ab)
{
return _cmsQuickSaturateWord((ab + 128.0) * 256.0);
}
static
cmsFloat64Number L2float4(cmsUInt16Number v)
{
return (cmsFloat64Number) v / 655.35;
}
// the a/b part
static
cmsFloat64Number ab2float4(cmsUInt16Number v)
{
return ((cmsFloat64Number) v / 257.0) - 128.0;
}
void CMSEXPORT cmsLabEncoded2FloatV2(cmsCIELab* Lab, const cmsUInt16Number wLab[3])
{
Lab->L = L2float2(wLab[0]);
Lab->a = ab2float2(wLab[1]);
Lab->b = ab2float2(wLab[2]);
}
void CMSEXPORT cmsLabEncoded2Float(cmsCIELab* Lab, const cmsUInt16Number wLab[3])
{
Lab->L = L2float4(wLab[0]);
Lab->a = ab2float4(wLab[1]);
Lab->b = ab2float4(wLab[2]);
}
static
cmsFloat64Number Clamp_L_doubleV2(cmsFloat64Number L)
{
const cmsFloat64Number L_max = (cmsFloat64Number) (0xFFFF * 100.0) / 0xFF00;
if (L < 0) L = 0;
if (L > L_max) L = L_max;
return L;
}
static
cmsFloat64Number Clamp_ab_doubleV2(cmsFloat64Number ab)
{
if (ab < MIN_ENCODEABLE_ab2) ab = MIN_ENCODEABLE_ab2;
if (ab > MAX_ENCODEABLE_ab2) ab = MAX_ENCODEABLE_ab2;
return ab;
}
void CMSEXPORT cmsFloat2LabEncodedV2(cmsUInt16Number wLab[3], const cmsCIELab* fLab)
{
cmsCIELab Lab;
Lab.L = Clamp_L_doubleV2(fLab ->L);
Lab.a = Clamp_ab_doubleV2(fLab ->a);
Lab.b = Clamp_ab_doubleV2(fLab ->b);
wLab[0] = L2Fix2(Lab.L);
wLab[1] = ab2Fix2(Lab.a);
wLab[2] = ab2Fix2(Lab.b);
}
static
cmsFloat64Number Clamp_L_doubleV4(cmsFloat64Number L)
{
if (L < 0) L = 0;
if (L > 100.0) L = 100.0;
return L;
}
static
cmsFloat64Number Clamp_ab_doubleV4(cmsFloat64Number ab)
{
if (ab < MIN_ENCODEABLE_ab4) ab = MIN_ENCODEABLE_ab4;
if (ab > MAX_ENCODEABLE_ab4) ab = MAX_ENCODEABLE_ab4;
return ab;
}
static
cmsUInt16Number L2Fix4(cmsFloat64Number L)
{
return _cmsQuickSaturateWord(L * 655.35);
}
static
cmsUInt16Number ab2Fix4(cmsFloat64Number ab)
{
return _cmsQuickSaturateWord((ab + 128.0) * 257.0);
}
void CMSEXPORT cmsFloat2LabEncoded(cmsUInt16Number wLab[3], const cmsCIELab* fLab)
{
cmsCIELab Lab;
Lab.L = Clamp_L_doubleV4(fLab ->L);
Lab.a = Clamp_ab_doubleV4(fLab ->a);
Lab.b = Clamp_ab_doubleV4(fLab ->b);
wLab[0] = L2Fix4(Lab.L);
wLab[1] = ab2Fix4(Lab.a);
wLab[2] = ab2Fix4(Lab.b);
}
// Auxiliary: convert to Radians
static
cmsFloat64Number RADIANS(cmsFloat64Number deg)
{
return (deg * M_PI) / 180.;
}
// Auxiliary: atan2 but operating in degrees and returning 0 if a==b==0
static
cmsFloat64Number atan2deg(cmsFloat64Number a, cmsFloat64Number b)
{
cmsFloat64Number h;
if (a == 0 && b == 0)
h = 0;
else
h = atan2(a, b);
h *= (180. / M_PI);
while (h > 360.)
h -= 360.;
while ( h < 0)
h += 360.;
return h;
}
// Auxiliary: Square
static
cmsFloat64Number Sqr(cmsFloat64Number v)
{
return v * v;
}
// From cylindrical coordinates. No check is performed, then negative values are allowed
void CMSEXPORT cmsLab2LCh(cmsCIELCh* LCh, const cmsCIELab* Lab)
{
LCh -> L = Lab -> L;
LCh -> C = pow(Sqr(Lab ->a) + Sqr(Lab ->b), 0.5);
LCh -> h = atan2deg(Lab ->b, Lab ->a);
}
// To cylindrical coordinates. No check is performed, then negative values are allowed
void CMSEXPORT cmsLCh2Lab(cmsCIELab* Lab, const cmsCIELCh* LCh)
{
cmsFloat64Number h = (LCh -> h * M_PI) / 180.0;
Lab -> L = LCh -> L;
Lab -> a = LCh -> C * cos(h);
Lab -> b = LCh -> C * sin(h);
}
// In XYZ All 3 components are encoded using 1.15 fixed point
static
cmsUInt16Number XYZ2Fix(cmsFloat64Number d)
{
return _cmsQuickSaturateWord(d * 32768.0);
}
void CMSEXPORT cmsFloat2XYZEncoded(cmsUInt16Number XYZ[3], const cmsCIEXYZ* fXYZ)
{
cmsCIEXYZ xyz;
xyz.X = fXYZ -> X;
xyz.Y = fXYZ -> Y;
xyz.Z = fXYZ -> Z;
// Clamp to encodeable values.
if (xyz.Y <= 0) {
xyz.X = 0;
xyz.Y = 0;
xyz.Z = 0;
}
if (xyz.X > MAX_ENCODEABLE_XYZ)
xyz.X = MAX_ENCODEABLE_XYZ;
if (xyz.X < 0)
xyz.X = 0;
if (xyz.Y > MAX_ENCODEABLE_XYZ)
xyz.Y = MAX_ENCODEABLE_XYZ;
if (xyz.Y < 0)
xyz.Y = 0;
if (xyz.Z > MAX_ENCODEABLE_XYZ)
xyz.Z = MAX_ENCODEABLE_XYZ;
if (xyz.Z < 0)
xyz.Z = 0;
XYZ[0] = XYZ2Fix(xyz.X);
XYZ[1] = XYZ2Fix(xyz.Y);
XYZ[2] = XYZ2Fix(xyz.Z);
}
// To convert from Fixed 1.15 point to cmsFloat64Number
static
cmsFloat64Number XYZ2float(cmsUInt16Number v)
{
cmsS15Fixed16Number fix32;
// From 1.15 to 15.16
fix32 = v << 1;
// From fixed 15.16 to cmsFloat64Number
return _cms15Fixed16toDouble(fix32);
}
void CMSEXPORT cmsXYZEncoded2Float(cmsCIEXYZ* fXYZ, const cmsUInt16Number XYZ[3])
{
fXYZ -> X = XYZ2float(XYZ[0]);
fXYZ -> Y = XYZ2float(XYZ[1]);
fXYZ -> Z = XYZ2float(XYZ[2]);
}
// Returns dE on two Lab values
cmsFloat64Number CMSEXPORT cmsDeltaE(const cmsCIELab* Lab1, const cmsCIELab* Lab2)
{
cmsFloat64Number dL, da, db;
dL = fabs(Lab1 -> L - Lab2 -> L);
da = fabs(Lab1 -> a - Lab2 -> a);
db = fabs(Lab1 -> b - Lab2 -> b);
return pow(Sqr(dL) + Sqr(da) + Sqr(db), 0.5);
}
// Return the CIE94 Delta E
cmsFloat64Number CMSEXPORT cmsCIE94DeltaE(const cmsCIELab* Lab1, const cmsCIELab* Lab2)
{
cmsCIELCh LCh1, LCh2;
cmsFloat64Number dE, dL, dC, dh, dhsq;
cmsFloat64Number c12, sc, sh;
dL = fabs(Lab1 ->L - Lab2 ->L);
cmsLab2LCh(&LCh1, Lab1);
cmsLab2LCh(&LCh2, Lab2);
dC = fabs(LCh1.C - LCh2.C);
dE = cmsDeltaE(Lab1, Lab2);
dhsq = Sqr(dE) - Sqr(dL) - Sqr(dC);
if (dhsq < 0)
dh = 0;
else
dh = pow(dhsq, 0.5);
c12 = sqrt(LCh1.C * LCh2.C);
sc = 1.0 + (0.048 * c12);
sh = 1.0 + (0.014 * c12);
return sqrt(Sqr(dL) + Sqr(dC) / Sqr(sc) + Sqr(dh) / Sqr(sh));
}
// Auxiliary
static
cmsFloat64Number ComputeLBFD(const cmsCIELab* Lab)
{
cmsFloat64Number yt;
if (Lab->L > 7.996969)
yt = (Sqr((Lab->L+16)/116)*((Lab->L+16)/116))*100;
else
yt = 100 * (Lab->L / 903.3);
return (54.6 * (M_LOG10E * (log(yt + 1.5))) - 9.6);
}
// bfd - gets BFD(1:1) difference between Lab1, Lab2
cmsFloat64Number CMSEXPORT cmsBFDdeltaE(const cmsCIELab* Lab1, const cmsCIELab* Lab2)
{
cmsFloat64Number lbfd1,lbfd2,AveC,Aveh,dE,deltaL,
deltaC,deltah,dc,t,g,dh,rh,rc,rt,bfd;
cmsCIELCh LCh1, LCh2;
lbfd1 = ComputeLBFD(Lab1);
lbfd2 = ComputeLBFD(Lab2);
deltaL = lbfd2 - lbfd1;
cmsLab2LCh(&LCh1, Lab1);
cmsLab2LCh(&LCh2, Lab2);
deltaC = LCh2.C - LCh1.C;
AveC = (LCh1.C+LCh2.C)/2;
Aveh = (LCh1.h+LCh2.h)/2;
dE = cmsDeltaE(Lab1, Lab2);
if (Sqr(dE)>(Sqr(Lab2->L-Lab1->L)+Sqr(deltaC)))
deltah = sqrt(Sqr(dE)-Sqr(Lab2->L-Lab1->L)-Sqr(deltaC));
else
deltah =0;
dc = 0.035 * AveC / (1 + 0.00365 * AveC)+0.521;
g = sqrt(Sqr(Sqr(AveC))/(Sqr(Sqr(AveC))+14000));
t = 0.627+(0.055*cos((Aveh-254)/(180/M_PI))-
0.040*cos((2*Aveh-136)/(180/M_PI))+
0.070*cos((3*Aveh-31)/(180/M_PI))+
0.049*cos((4*Aveh+114)/(180/M_PI))-
0.015*cos((5*Aveh-103)/(180/M_PI)));
dh = dc*(g*t+1-g);
rh = -0.260*cos((Aveh-308)/(180/M_PI))-
0.379*cos((2*Aveh-160)/(180/M_PI))-
0.636*cos((3*Aveh+254)/(180/M_PI))+
0.226*cos((4*Aveh+140)/(180/M_PI))-
0.194*cos((5*Aveh+280)/(180/M_PI));
rc = sqrt((AveC*AveC*AveC*AveC*AveC*AveC)/((AveC*AveC*AveC*AveC*AveC*AveC)+70000000));
rt = rh*rc;
bfd = sqrt(Sqr(deltaL)+Sqr(deltaC/dc)+Sqr(deltah/dh)+(rt*(deltaC/dc)*(deltah/dh)));
return bfd;
}
// cmc - CMC(l:c) difference between Lab1, Lab2
cmsFloat64Number CMSEXPORT cmsCMCdeltaE(const cmsCIELab* Lab1, const cmsCIELab* Lab2, cmsFloat64Number l, cmsFloat64Number c)
{
cmsFloat64Number dE,dL,dC,dh,sl,sc,sh,t,f,cmc;
cmsCIELCh LCh1, LCh2;
if (Lab1 ->L == 0 && Lab2 ->L == 0) return 0;
cmsLab2LCh(&LCh1, Lab1);
cmsLab2LCh(&LCh2, Lab2);
dL = Lab2->L-Lab1->L;
dC = LCh2.C-LCh1.C;
dE = cmsDeltaE(Lab1, Lab2);
if (Sqr(dE)>(Sqr(dL)+Sqr(dC)))
dh = sqrt(Sqr(dE)-Sqr(dL)-Sqr(dC));
else
dh =0;
if ((LCh1.h > 164) && (LCh1.h < 345))
t = 0.56 + fabs(0.2 * cos(((LCh1.h + 168)/(180/M_PI))));
else
t = 0.36 + fabs(0.4 * cos(((LCh1.h + 35 )/(180/M_PI))));
sc = 0.0638 * LCh1.C / (1 + 0.0131 * LCh1.C) + 0.638;
sl = 0.040975 * Lab1->L /(1 + 0.01765 * Lab1->L);
if (Lab1->L<16)
sl = 0.511;
f = sqrt((LCh1.C * LCh1.C * LCh1.C * LCh1.C)/((LCh1.C * LCh1.C * LCh1.C * LCh1.C)+1900));
sh = sc*(t*f+1-f);
cmc = sqrt(Sqr(dL/(l*sl))+Sqr(dC/(c*sc))+Sqr(dh/sh));
return cmc;
}
// dE2000 The weightings KL, KC and KH can be modified to reflect the relative
// importance of lightness, chroma and hue in different industrial applications
cmsFloat64Number CMSEXPORT cmsCIE2000DeltaE(const cmsCIELab* Lab1, const cmsCIELab* Lab2,
cmsFloat64Number Kl, cmsFloat64Number Kc, cmsFloat64Number Kh)
{
cmsFloat64Number L1 = Lab1->L;
cmsFloat64Number a1 = Lab1->a;
cmsFloat64Number b1 = Lab1->b;
cmsFloat64Number C = sqrt( Sqr(a1) + Sqr(b1) );
cmsFloat64Number Ls = Lab2 ->L;
cmsFloat64Number as = Lab2 ->a;
cmsFloat64Number bs = Lab2 ->b;
cmsFloat64Number Cs = sqrt( Sqr(as) + Sqr(bs) );
cmsFloat64Number G = 0.5 * ( 1 - sqrt(pow((C + Cs) / 2 , 7.0) / (pow((C + Cs) / 2, 7.0) + pow(25.0, 7.0) ) ));
cmsFloat64Number a_p = (1 + G ) * a1;
cmsFloat64Number b_p = b1;
cmsFloat64Number C_p = sqrt( Sqr(a_p) + Sqr(b_p));
cmsFloat64Number h_p = atan2deg(b_p, a_p);
cmsFloat64Number a_ps = (1 + G) * as;
cmsFloat64Number b_ps = bs;
cmsFloat64Number C_ps = sqrt(Sqr(a_ps) + Sqr(b_ps));
cmsFloat64Number h_ps = atan2deg(b_ps, a_ps);
cmsFloat64Number meanC_p =(C_p + C_ps) / 2;
cmsFloat64Number hps_plus_hp = h_ps + h_p;
cmsFloat64Number hps_minus_hp = h_ps - h_p;
cmsFloat64Number meanh_p = fabs(hps_minus_hp) <= 180.000001 ? (hps_plus_hp)/2 :
(hps_plus_hp) < 360 ? (hps_plus_hp + 360)/2 :
(hps_plus_hp - 360)/2;
cmsFloat64Number delta_h = (hps_minus_hp) <= -180.000001 ? (hps_minus_hp + 360) :
(hps_minus_hp) > 180 ? (hps_minus_hp - 360) :
(hps_minus_hp);
cmsFloat64Number delta_L = (Ls - L1);
cmsFloat64Number delta_C = (C_ps - C_p );
cmsFloat64Number delta_H =2 * sqrt(C_ps*C_p) * sin(RADIANS(delta_h) / 2);
cmsFloat64Number T = 1 - 0.17 * cos(RADIANS(meanh_p-30))
+ 0.24 * cos(RADIANS(2*meanh_p))
+ 0.32 * cos(RADIANS(3*meanh_p + 6))
- 0.2 * cos(RADIANS(4*meanh_p - 63));
cmsFloat64Number Sl = 1 + (0.015 * Sqr((Ls + L1) /2- 50) )/ sqrt(20 + Sqr( (Ls+L1)/2 - 50) );
cmsFloat64Number Sc = 1 + 0.045 * (C_p + C_ps)/2;
cmsFloat64Number Sh = 1 + 0.015 * ((C_ps + C_p)/2) * T;
cmsFloat64Number delta_ro = 30 * exp( -Sqr(((meanh_p - 275 ) / 25)));
cmsFloat64Number Rc = 2 * sqrt(( pow(meanC_p, 7.0) )/( pow(meanC_p, 7.0) + pow(25.0, 7.0)));
cmsFloat64Number Rt = -sin(2 * RADIANS(delta_ro)) * Rc;
cmsFloat64Number deltaE00 = sqrt( Sqr(delta_L /(Sl * Kl)) +
Sqr(delta_C/(Sc * Kc)) +
Sqr(delta_H/(Sh * Kh)) +
Rt*(delta_C/(Sc * Kc)) * (delta_H / (Sh * Kh)));
return deltaE00;
}
// This function returns a number of gridpoints to be used as LUT table. It assumes same number
// of gripdpoints in all dimensions. Flags may override the choice.
cmsUInt32Number CMSEXPORT _cmsReasonableGridpointsByColorspace(cmsColorSpaceSignature Colorspace, cmsUInt32Number dwFlags)
{
cmsUInt32Number nChannels;
// Already specified?
if (dwFlags & 0x00FF0000) {
// Yes, grab'em
return (dwFlags >> 16) & 0xFF;
}
nChannels = cmsChannelsOf(Colorspace);
// HighResPrecalc is maximum resolution
if (dwFlags & cmsFLAGS_HIGHRESPRECALC) {
if (nChannels > 4)
return 7; // 7 for Hifi
if (nChannels == 4) // 23 for CMYK
return 23;
return 49; // 49 for RGB and others
}
// LowResPrecal is lower resolution
if (dwFlags & cmsFLAGS_LOWRESPRECALC) {
if (nChannels > 4)
return 6; // 6 for more than 4 channels
if (nChannels == 1)
return 33; // For monochrome
return 17; // 17 for remaining
}
// Default values
if (nChannels > 4)
return 7; // 7 for Hifi
if (nChannels == 4)
return 17; // 17 for CMYK
return 33; // 33 for RGB
}
cmsBool _cmsEndPointsBySpace(cmsColorSpaceSignature Space,
cmsUInt16Number **White,
cmsUInt16Number **Black,
cmsUInt32Number *nOutputs)
{
// Only most common spaces
static cmsUInt16Number RGBblack[4] = { 0, 0, 0 };
static cmsUInt16Number RGBwhite[4] = { 0xffff, 0xffff, 0xffff };
static cmsUInt16Number CMYKblack[4] = { 0xffff, 0xffff, 0xffff, 0xffff }; // 400% of ink
static cmsUInt16Number CMYKwhite[4] = { 0, 0, 0, 0 };
static cmsUInt16Number LABblack[4] = { 0, 0x8080, 0x8080 }; // V4 Lab encoding
static cmsUInt16Number LABwhite[4] = { 0xFFFF, 0x8080, 0x8080 };
static cmsUInt16Number CMYblack[4] = { 0xffff, 0xffff, 0xffff };
static cmsUInt16Number CMYwhite[4] = { 0, 0, 0 };
static cmsUInt16Number Grayblack[4] = { 0 };
static cmsUInt16Number GrayWhite[4] = { 0xffff };
switch (Space) {
case cmsSigGrayData: if (White) *White = GrayWhite;
if (Black) *Black = Grayblack;
if (nOutputs) *nOutputs = 1;
return TRUE;
case cmsSigRgbData: if (White) *White = RGBwhite;
if (Black) *Black = RGBblack;
if (nOutputs) *nOutputs = 3;
return TRUE;
case cmsSigLabData: if (White) *White = LABwhite;
if (Black) *Black = LABblack;
if (nOutputs) *nOutputs = 3;
return TRUE;
case cmsSigCmykData: if (White) *White = CMYKwhite;
if (Black) *Black = CMYKblack;
if (nOutputs) *nOutputs = 4;
return TRUE;
case cmsSigCmyData: if (White) *White = CMYwhite;
if (Black) *Black = CMYblack;
if (nOutputs) *nOutputs = 3;
return TRUE;
default:;
}
return FALSE;
}
// Several utilities -------------------------------------------------------
// Translate from our colorspace to ICC representation
cmsColorSpaceSignature CMSEXPORT _cmsICCcolorSpace(int OurNotation)
{
switch (OurNotation) {
case 1:
case PT_GRAY: return cmsSigGrayData;
case 2:
case PT_RGB: return cmsSigRgbData;
case PT_CMY: return cmsSigCmyData;
case PT_CMYK: return cmsSigCmykData;
case PT_YCbCr:return cmsSigYCbCrData;
case PT_YUV: return cmsSigLuvData;
case PT_XYZ: return cmsSigXYZData;
case PT_LabV2:
case PT_Lab: return cmsSigLabData;
case PT_YUVK: return cmsSigLuvKData;
case PT_HSV: return cmsSigHsvData;
case PT_HLS: return cmsSigHlsData;
case PT_Yxy: return cmsSigYxyData;
case PT_MCH1: return cmsSigMCH1Data;
case PT_MCH2: return cmsSigMCH2Data;
case PT_MCH3: return cmsSigMCH3Data;
case PT_MCH4: return cmsSigMCH4Data;
case PT_MCH5: return cmsSigMCH5Data;
case PT_MCH6: return cmsSigMCH6Data;
case PT_MCH7: return cmsSigMCH7Data;
case PT_MCH8: return cmsSigMCH8Data;
case PT_MCH9: return cmsSigMCH9Data;
case PT_MCH10: return cmsSigMCHAData;
case PT_MCH11: return cmsSigMCHBData;
case PT_MCH12: return cmsSigMCHCData;
case PT_MCH13: return cmsSigMCHDData;
case PT_MCH14: return cmsSigMCHEData;
case PT_MCH15: return cmsSigMCHFData;
default: return (cmsColorSpaceSignature) 0;
}
}
int CMSEXPORT _cmsLCMScolorSpace(cmsColorSpaceSignature ProfileSpace)
{
switch (ProfileSpace) {
case cmsSigGrayData: return PT_GRAY;
case cmsSigRgbData: return PT_RGB;
case cmsSigCmyData: return PT_CMY;
case cmsSigCmykData: return PT_CMYK;
case cmsSigYCbCrData:return PT_YCbCr;
case cmsSigLuvData: return PT_YUV;
case cmsSigXYZData: return PT_XYZ;
case cmsSigLabData: return PT_Lab;
case cmsSigLuvKData: return PT_YUVK;
case cmsSigHsvData: return PT_HSV;
case cmsSigHlsData: return PT_HLS;
case cmsSigYxyData: return PT_Yxy;
case cmsSig1colorData:
case cmsSigMCH1Data: return PT_MCH1;
case cmsSig2colorData:
case cmsSigMCH2Data: return PT_MCH2;
case cmsSig3colorData:
case cmsSigMCH3Data: return PT_MCH3;
case cmsSig4colorData:
case cmsSigMCH4Data: return PT_MCH4;
case cmsSig5colorData:
case cmsSigMCH5Data: return PT_MCH5;
case cmsSig6colorData:
case cmsSigMCH6Data: return PT_MCH6;
case cmsSigMCH7Data:
case cmsSig7colorData:return PT_MCH7;
case cmsSigMCH8Data:
case cmsSig8colorData:return PT_MCH8;
case cmsSigMCH9Data:
case cmsSig9colorData:return PT_MCH9;
case cmsSigMCHAData:
case cmsSig10colorData:return PT_MCH10;
case cmsSigMCHBData:
case cmsSig11colorData:return PT_MCH11;
case cmsSigMCHCData:
case cmsSig12colorData:return PT_MCH12;
case cmsSigMCHDData:
case cmsSig13colorData:return PT_MCH13;
case cmsSigMCHEData:
case cmsSig14colorData:return PT_MCH14;
case cmsSigMCHFData:
case cmsSig15colorData:return PT_MCH15;
default: return (cmsColorSpaceSignature) 0;
}
}
cmsInt32Number CMSEXPORT cmsChannelsOfColorSpace(cmsColorSpaceSignature ColorSpace)
{
switch (ColorSpace) {
case cmsSigMCH1Data:
case cmsSig1colorData:
case cmsSigGrayData: return 1;
case cmsSigMCH2Data:
case cmsSig2colorData: return 2;
case cmsSigXYZData:
case cmsSigLabData:
case cmsSigLuvData:
case cmsSigYCbCrData:
case cmsSigYxyData:
case cmsSigRgbData:
case cmsSigHsvData:
case cmsSigHlsData:
case cmsSigCmyData:
case cmsSigMCH3Data:
case cmsSig3colorData: return 3;
case cmsSigLuvKData:
case cmsSigCmykData:
case cmsSigMCH4Data:
case cmsSig4colorData: return 4;
case cmsSigMCH5Data:
case cmsSig5colorData: return 5;
case cmsSigMCH6Data:
case cmsSig6colorData: return 6;
case cmsSigMCH7Data:
case cmsSig7colorData: return 7;
case cmsSigMCH8Data:
case cmsSig8colorData: return 8;
case cmsSigMCH9Data:
case cmsSig9colorData: return 9;
case cmsSigMCHAData:
case cmsSig10colorData: return 10;
case cmsSigMCHBData:
case cmsSig11colorData: return 11;
case cmsSigMCHCData:
case cmsSig12colorData: return 12;
case cmsSigMCHDData:
case cmsSig13colorData: return 13;
case cmsSigMCHEData:
case cmsSig14colorData: return 14;
case cmsSigMCHFData:
case cmsSig15colorData: return 15;
default: return -1;
}
}
/**
* DEPRECATED: Provided for compatibility only
*/
cmsUInt32Number CMSEXPORT cmsChannelsOf(cmsColorSpaceSignature ColorSpace)
{
int n = cmsChannelsOfColorSpace(ColorSpace);
if (n < 0) return 3;
return (cmsUInt32Number)n;
}
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