Merge branch '1.0' of ssh://main.carlh.net/home/carl/git/libdcp into 1.0

[libdcp.git] / test / colour_conversion_test.cc

diff --git a/test/colour_conversion_test.cc b/test/colour_conversion_test.cc
index 9111b91845aa7baceaafe2c6b12db6f5e276d574..b743497bfc27bcd9f7bc3b5666464322b6e71236 100644 (file)
--- a/test/colour_conversion_test.cc
+++ b/test/colour_conversion_test.cc
@@ -28,9 +28,9 @@ using boost::shared_ptr;
 using namespace dcp;
 
 static void
-check_gamma (shared_ptr<const TransferFunction> tf, int bit_depth, float gamma)
+check_gamma (shared_ptr<const TransferFunction> tf, int bit_depth, bool inverse, float gamma)
 {
-       double const * lut = tf->lut (bit_depth);
+       double const * lut = tf->lut (bit_depth, inverse);
        int const count = rint (pow (2.0, bit_depth));
 
        for (int i = 0; i < count; ++i) {
@@ -39,9 +39,9 @@ check_gamma (shared_ptr<const TransferFunction> tf, int bit_depth, float gamma)
 }
 
 static void
-check_modified_gamma (shared_ptr<const TransferFunction> tf, int bit_depth, double power, double threshold, double A, double B)
+check_modified_gamma (shared_ptr<const TransferFunction> tf, int bit_depth, bool inverse, double power, double threshold, double A, double B)
 {
-       double const * lut = tf->lut (bit_depth);
+       double const * lut = tf->lut (bit_depth, inverse);
        int const count = rint (pow (2.0, bit_depth));
 
        for (int i = 0; i < count; ++i) {
@@ -54,29 +54,51 @@ check_modified_gamma (shared_ptr<const TransferFunction> tf, int bit_depth, doub
        }
 }
 
+/** Check that the gamma correction LUTs are right for sRGB */
 BOOST_AUTO_TEST_CASE (colour_conversion_test1)
 {
        ColourConversion cc = ColourConversion::srgb_to_xyz ();
 
-       check_modified_gamma (cc.in(), 8, 2.4, 0.04045, 0.055, 12.92);
-       check_modified_gamma (cc.in(), 12, 2.4, 0.04045, 0.055, 12.92);
-       check_modified_gamma (cc.in(), 16, 2.4, 0.04045, 0.055, 12.92);
+       check_modified_gamma (cc.in(), 8, false, 2.4, 0.04045, 0.055, 12.92);
+       check_modified_gamma (cc.in(), 12, false, 2.4, 0.04045, 0.055, 12.92);
+       check_modified_gamma (cc.in(), 16, false, 2.4, 0.04045, 0.055, 12.92);
 
-       check_gamma (cc.out(), 8, 1 / 2.6);
-       check_gamma (cc.out(), 12, 1 / 2.6);
-       check_gamma (cc.out(), 16, 1 / 2.6);
+       check_gamma (cc.out(), 8, true, 1 / 2.6);
+       check_gamma (cc.out(), 12, true, 1 / 2.6);
+       check_gamma (cc.out(), 16, true, 1 / 2.6);
 }
 
+/** Check that the gamma correction LUTs are right for REC709 */
 BOOST_AUTO_TEST_CASE (colour_conversion_test2)
 {
        ColourConversion cc = ColourConversion::rec709_to_xyz ();
 
-       check_modified_gamma (cc.in(), 8, 1 / 0.45, 0.081, 0.099, 4.5);
-       check_modified_gamma (cc.in(), 12, 1 / 0.45, 0.081, 0.099, 4.5);
-       check_modified_gamma (cc.in(), 16, 1 / 0.45, 0.081, 0.099, 4.5);
+       check_modified_gamma (cc.in(), 8, false, 1 / 0.45, 0.081, 0.099, 4.5);
+       check_modified_gamma (cc.in(), 12, false, 1 / 0.45, 0.081, 0.099, 4.5);
+       check_modified_gamma (cc.in(), 16, false, 1 / 0.45, 0.081, 0.099, 4.5);
 
-       check_gamma (cc.out(), 8, 1 / 2.6);
-       check_gamma (cc.out(), 12, 1 / 2.6);
-       check_gamma (cc.out(), 16, 1 / 2.6);
+       check_gamma (cc.out(), 8, true, 1 / 2.6);
+       check_gamma (cc.out(), 12, true, 1 / 2.6);
+       check_gamma (cc.out(), 16, true, 1 / 2.6);
 }
 
+/** Check that the xyz_to_rgb matrix is the inverse of the rgb_to_xyz one */
+BOOST_AUTO_TEST_CASE (colour_conversion_matrix_test)
+{
+       ColourConversion c = ColourConversion::srgb_to_xyz ();
+
+       boost::numeric::ublas::matrix<double> A = c.rgb_to_xyz ();
+       boost::numeric::ublas::matrix<double> B = c.xyz_to_rgb ();
+
+       BOOST_CHECK_CLOSE (A(0, 0) * B(0, 0) + A(0, 1) * B(1, 0) + A(0, 2) * B(2, 0), 1, 0.1);
+       BOOST_CHECK (fabs (A(0, 0) * B(0, 1) + A(0, 1) * B(1, 1) + A(0, 2) * B(2, 1)) < 1e-6);
+       BOOST_CHECK (fabs (A(0, 0) * B(0, 2) + A(0, 1) * B(1, 2) + A(0, 2) * B(2, 2)) < 1e-6);
+
+       BOOST_CHECK (fabs (A(1, 0) * B(0, 0) + A(1, 1) * B(1, 0) + A(1, 2) * B(2, 0)) < 1e-6);
+       BOOST_CHECK_CLOSE (A(1, 0) * B(0, 1) + A(1, 1) * B(1, 1) + A(1, 2) * B(2, 1), 1, 0.1);
+       BOOST_CHECK (fabs (A(1, 0) * B(0, 2) + A(1, 1) * B(1, 2) + A(1, 2) * B(2, 2)) < 1e-6);
+
+       BOOST_CHECK (fabs (A(2, 0) * B(0, 0) + A(2, 1) * B(1, 0) + A(2, 2) * B(2, 0)) < 1e-6);
+       BOOST_CHECK (fabs (A(2, 0) * B(0, 1) + A(2, 1) * B(1, 1) + A(2, 2) * B(2, 1)) < 1e-6);
+       BOOST_CHECK_CLOSE (A(2, 0) * B(0, 2) + A(2, 1) * B(1, 2) + A(2, 2) * B(2, 2), 1, 0.1);
+}