Browse Source
color: move the CIEDE2000 distance code into the C++ file and
reorganise the CIE-1931 and CIE-1964 tables.legacy
sam
2 changed files with 568 additions and 1003 deletions
Unified View
Diff Options
-
+564 -942src/image/color/cie1931.cpp
-
+4 -61src/lol/image/color.h
+ 564
- 942
src/image/color/cie1931.cpp
File diff suppressed because it is too large
View File
+ 4
- 61
src/lol/image/color.h
View File
| @@ -214,68 +214,11 @@ public: | |||||
| * Return distance using the CIEDE2000 metric, | * Return distance using the CIEDE2000 metric, | ||||
| * input should be in CIE L*a*b*. | * input should be in CIE L*a*b*. | ||||
| */ | */ | ||||
| static float DistanceCIEDE2000(vec3 lab1, vec3 lab2) | |||||
| { | |||||
| float const deg2rad = 6.28318530718f / 360.f; | |||||
| float const rad2deg = 360.f / 6.28318530718f; | |||||
| float C1 = length(lab1.yz); | |||||
| float C2 = length(lab2.yz); | |||||
| float C_ = 0.5f * (C1 + C2); | |||||
| float L1 = lab1.x; | |||||
| float L2 = lab2.x; | |||||
| float dLp = L2 - L1; | |||||
| float L_ = 0.5f * (L1 + L2); | |||||
| float tmp1 = pow(C_, 7.f); | |||||
| float tmp2 = 1.5f - 0.5f * sqrt(tmp1 / (tmp1 + pow(25.f, 7.f))); | |||||
| float ap1 = lab1.y * tmp2; | |||||
| float ap2 = lab2.y * tmp2; | |||||
| float Cp1 = sqrt(ap1 * ap1 + lab1.z * lab1.z); | |||||
| float Cp2 = sqrt(ap2 * ap2 + lab2.z * lab2.z); | |||||
| float dCp = Cp2 - Cp1; | |||||
| float Cp_ = 0.5f * (Cp1 + Cp2); | |||||
| float hp1 = fmod(atan2(lab1.z, ap1) * rad2deg, 360.f); | |||||
| if (hp1 < 0.f) | |||||
| hp1 += 360.f; | |||||
| float hp2 = fmod(atan2(lab2.z, ap2) * rad2deg, 360.f); | |||||
| if (hp2 < 0.f) | |||||
| hp2 += 360.f; | |||||
| float dhp; | |||||
| if (abs(hp1 - hp2) <= 180.f) | |||||
| dhp = hp2 - hp1; | |||||
| else if (hp2 <= hp1) | |||||
| dhp = hp2 - hp1 + 360.f; | |||||
| else | |||||
| dhp = hp2 - hp1 - 360.f; | |||||
| float dHp = 2.f * sqrt(Cp1 * Cp2) * sin(dhp / 2.f * deg2rad); | |||||
| float Hp_; | |||||
| if (abs(hp1 - hp2) > 180.f) | |||||
| Hp_ = 0.5f * (hp1 + hp2 + 360.f); | |||||
| else | |||||
| Hp_ = 0.5f * (hp1 + hp2); | |||||
| float T = 1.f - 0.17f * cos((Hp_ - 30.f) * deg2rad) | |||||
| + 0.24f * cos(2 * Hp_ * deg2rad) | |||||
| + 0.32f * cos((3.f * Hp_ + 6.f) * deg2rad) | |||||
| - 0.20f * cos((4.f * Hp_ - 63.f) * deg2rad); | |||||
| float SL = 1.f + 0.015f * (L_ - 50) * (L_ - 50) | |||||
| / sqrt(20.f + (L_ - 50) * (L_ - 50)); | |||||
| float SC = 1.f + 0.045f * Cp_; | |||||
| float SH = 1.f + 0.015f * Cp_ * T; | |||||
| float RT = -2.f * sqrt(pow(Cp_, 7.f) / (pow(Cp_, 7.f) + pow(25.f, 7.f))) | |||||
| * sin(60.f * deg2rad * exp(-pow((Hp_ - 275.f) / 25.f, 2.f))); | |||||
| dLp /= SL; | |||||
| dCp /= SC; | |||||
| dHp /= SH; | |||||
| return sqrt(dLp * dLp + dCp * dCp + dHp * dHp + RT * dCp * dHp); | |||||
| } | |||||
| static float DistanceCIEDE2000(vec3 lab1, vec3 lab2); | |||||
| /* Convert a wavelength to an xyY fully saturated colour */ | |||||
| /* | |||||
| * Convert a wavelength into an xyY fully saturated colour. | |||||
| */ | |||||
| static vec3 WavelengthToCIExyY(float nm); | static vec3 WavelengthToCIExyY(float nm); | ||||
| }; | }; | ||||