- refactored

2022-06-30 13:32:40 +02:00
parent 77cd5261b1
commit 776932e5d1
144 changed files with 0 additions and 38 deletions
@@ -0,0 +1,47 @@
+% function [rgb] = xyz2rgb(xyz)
+%  
+% // C-Code
+% ref_X =  95.047        //Observer = 2°, Illuminant = D65
+% ref_Y = 100.000
+% ref_Z = 108.883
+%
+% var_X = X / 100        //X = From 0 to ref_X
+% var_Y = Y / 100        //Y = From 0 to ref_Y
+% var_Z = Z / 100        //Z = From 0 to ref_Y
+%
+% var_R = var_X *  3.2406 + var_Y * -1.5372 + var_Z * -0.4986
+% var_G = var_X * -0.9689 + var_Y *  1.8758 + var_Z *  0.0415
+% var_B = var_X *  0.0557 + var_Y * -0.2040 + var_Z *  1.0570
+%
+% if ( var_R > 0.0031308 ) var_R = 1.055 * ( var_R ^ ( 1 / 2.4 ) ) - 0.055
+% else                     var_R = 12.92 * var_R
+% if ( var_G > 0.0031308 ) var_G = 1.055 * ( var_G ^ ( 1 / 2.4 ) ) - 0.055
+% else                     var_G = 12.92 * var_G
+% if ( var_B > 0.0031308 ) var_B = 1.055 * ( var_B ^ ( 1 / 2.4 ) ) - 0.055
+% else                     var_B = 12.92 * var_B
+%
+% Source http://www.easyrgb.com
+
+function [rgb] = xyz2rgb(xyz)
+[m,n] = size(xyz);
+
+if ((m ~= 3) & (n == 3))
+    xyz = xyz';
+end;
+
+% Observer = 2°, Illuminant = D65
+t_mat = [[  3.240479 -1.537150 -0.498535 ]
+         [ -0.969256  1.875992  0.041556 ]
+         [  0.055648 -0.204043  1.057311 ]];
+
+rgb_k = t_mat * xyz;
+rgb = f1(rgb_k);
+
+function rgb = f1(rgb_k)
+thresh_n = 0.0031308;
+
+[idx_m,idx_n] = find(rgb_k > thresh_n);
+rgb(idx_m,idx_n) = 1.055*(rgb_k(idx_m,idx_n).^(1/2.4)) - 0.055;
+
+[idx_m,idx_n] = find(rgb_k <= thresh_n);
+rgb(idx_m,idx_n) = 12.92*rgb_k(idx_m,idx_n);