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) {
}
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) {
}
}
+/** 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, 2.4, 0.081, 0.099, 4.5);
- check_modified_gamma (cc.in(), 12, 2.4, 0.081, 0.099, 4.5);
- check_modified_gamma (cc.in(), 16, 2.4, 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);
+}