X-Git-Url: https://git.sesse.net/?p=movit;a=blobdiff_plain;f=colorspace_conversion_effect.cpp;h=2b8a0ca329fd34b3d535fca0cbdfb56584b8ff1d;hp=3f075d2b721141ef6c13428c24b93c854d4879f3;hb=8e9f58fec54a4c879035b214fd7411f6ff7b3a32;hpb=2c9711e213679e11bea1b0e86bb46af442b22ee0 diff --git a/colorspace_conversion_effect.cpp b/colorspace_conversion_effect.cpp index 3f075d2..2b8a0ca 100644 --- a/colorspace_conversion_effect.cpp +++ b/colorspace_conversion_effect.cpp @@ -1,24 +1,29 @@ #include - +#include #include #include "colorspace_conversion_effect.h" +#include "d65.h" #include "util.h" using namespace Eigen; +using namespace std; + +namespace movit { // Color coordinates from Rec. 709; sRGB uses the same primaries. -double rec709_x_R = 0.640, rec709_x_G = 0.300, rec709_x_B = 0.150; -double rec709_y_R = 0.330, rec709_y_G = 0.600, rec709_y_B = 0.060; +static const double rec709_x_R = 0.640, rec709_x_G = 0.300, rec709_x_B = 0.150; +static const double rec709_y_R = 0.330, rec709_y_G = 0.600, rec709_y_B = 0.060; // Color coordinates from Rec. 601. (Separate for 525- and 625-line systems.) -double rec601_525_x_R = 0.630, rec601_525_x_G = 0.310, rec601_525_x_B = 0.155; -double rec601_525_y_R = 0.340, rec601_525_y_G = 0.595, rec601_525_y_B = 0.070; -double rec601_625_x_R = 0.640, rec601_625_x_G = 0.290, rec601_625_x_B = 0.150; -double rec601_625_y_R = 0.330, rec601_625_y_G = 0.600, rec601_625_y_B = 0.060; +static const double rec601_525_x_R = 0.630, rec601_525_x_G = 0.310, rec601_525_x_B = 0.155; +static const double rec601_525_y_R = 0.340, rec601_525_y_G = 0.595, rec601_525_y_B = 0.070; +static const double rec601_625_x_R = 0.640, rec601_625_x_G = 0.290, rec601_625_x_B = 0.150; +static const double rec601_625_y_R = 0.330, rec601_625_y_G = 0.600, rec601_625_y_B = 0.060; -// The D65 white point. Given in both Rec. 601 and 709. -double d65_x = 0.3127, d65_y = 0.3290; +// Color coordinates from Rec. 2020. +static const double rec2020_x_R = 0.708, rec2020_x_G = 0.170, rec2020_x_B = 0.131; +static const double rec2020_y_R = 0.292, rec2020_y_G = 0.797, rec2020_y_B = 0.046; ColorspaceConversionEffect::ColorspaceConversionEffect() : source_space(COLORSPACE_sRGB), @@ -28,7 +33,7 @@ ColorspaceConversionEffect::ColorspaceConversionEffect() register_int("destination_space", (int *)&destination_space); } -Matrix3d get_xyz_matrix(Colorspace space) +Matrix3d ColorspaceConversionEffect::get_xyz_matrix(Colorspace space) { if (space == COLORSPACE_XYZ) { return Matrix3d::Identity(); @@ -50,6 +55,10 @@ Matrix3d get_xyz_matrix(Colorspace space) x_R = rec601_625_x_R; x_G = rec601_625_x_G; x_B = rec601_625_x_B; y_R = rec601_625_y_R; y_G = rec601_625_y_G; y_B = rec601_625_y_B; break; + case COLORSPACE_REC_2020: + x_R = rec2020_x_R; x_G = rec2020_x_G; x_B = rec2020_x_B; + y_R = rec2020_y_R; y_G = rec2020_y_G; y_B = rec2020_y_B; + break; default: assert(false); } @@ -59,14 +68,6 @@ Matrix3d get_xyz_matrix(Colorspace space) double z_G = 1.0 - x_G - y_G; double z_B = 1.0 - x_B - y_B; - // Find the XYZ coordinates of D65 (white point for both Rec. 601 and 709), - // normalized so that Y=1. - Vector3d d65_XYZ( - d65_x / d65_y, - 1.0, - (1.0 - d65_x - d65_y) / d65_y - ); - // We have, for each primary (example is with red): // // X_R / (X_R + Y_R + Z_R) = x_R @@ -75,8 +76,8 @@ Matrix3d get_xyz_matrix(Colorspace space) // // Some algebraic fiddling yields (unsurprisingly): // - // X_R = (x_R / y_R) Y_R - // Z_R = (z_R / y_R) Y_R + // X_R = (x_R / y_R) Y_R (so define k1 = x_R / y_R) + // Z_R = (z_R / y_R) Y_R (so define k4 = z_R / y_R) // // We also know that since RGB=(1,1,1) should give us the // D65 illuminant, we must have @@ -85,8 +86,8 @@ Matrix3d get_xyz_matrix(Colorspace space) // Y_R + Y_G + Y_B = D65_Y // Z_R + Z_G + Z_B = D65_Z // - // But since we already know how to express Y and Z by - // some constant multiple of X, this reduces to + // But since we already know how to express X and Z by + // some constant multiple of Y, this reduces to // // k1 Y_R + k2 Y_G + k3 Y_B = D65_X // Y_R + Y_G + Y_B = D65_Y @@ -107,6 +108,7 @@ Matrix3d get_xyz_matrix(Colorspace space) temp(2,1) = z_G / y_G; temp(2,2) = z_B / y_B; + Vector3d d65_XYZ(d65_X, d65_Y, d65_Z); Vector3d Y_RGB = temp.inverse() * d65_XYZ; // Now convert xyY -> XYZ. @@ -127,7 +129,7 @@ Matrix3d get_xyz_matrix(Colorspace space) return m; } -std::string ColorspaceConversionEffect::output_fragment_shader() +string ColorspaceConversionEffect::output_fragment_shader() { // Create a matrix to convert from source space -> XYZ, // another matrix to convert from XYZ -> destination space, @@ -142,3 +144,5 @@ std::string ColorspaceConversionEffect::output_fragment_shader() return output_glsl_mat3("PREFIX(conversion_matrix)", m) + read_file("colorspace_conversion_effect.frag"); } + +} // namespace movit