From 75788462338b1b4f464d075465da3cb372c40004 Mon Sep 17 00:00:00 2001 From: Carl Hetherington Date: Sat, 27 Dec 2014 20:02:16 +0000 Subject: Change colourspace handling round a bit: - move the essence of GammaLUT into TransferFunction and handle different bit depths more neatly - add ColourConversion to describe input gamma correction, colour transformation and then output gamma correction in one class. - add default ColourConversions for sRGB->XYZ, Rec709->XYZ and XYZ->RGB. --- src/colour_conversion.cc | 75 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 75 insertions(+) create mode 100644 src/colour_conversion.cc (limited to 'src/colour_conversion.cc') diff --git a/src/colour_conversion.cc b/src/colour_conversion.cc new file mode 100644 index 00000000..28edf9bc --- /dev/null +++ b/src/colour_conversion.cc @@ -0,0 +1,75 @@ +/* + Copyright (C) 2014 Carl Hetherington + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + +*/ + +#include "colour_conversion.h" +#include "gamma_transfer_function.h" +#include "modified_gamma_transfer_function.h" +#include "colour_matrix.h" + +using boost::shared_ptr; +using namespace dcp; + +ColourConversion ColourConversion::srgb_to_xyz ( + shared_ptr (new ModifiedGammaTransferFunction (2.4, 0.04045, 0.055, 12.92)), + dcp::colour_matrix::srgb_to_xyz, + shared_ptr (new GammaTransferFunction (2.6)) + ); + +/* XXX: what sort of RGB is this...? */ +ColourConversion ColourConversion::xyz_to_rgb ( + shared_ptr (new GammaTransferFunction (2.6)), + dcp::colour_matrix::xyz_to_rgb, + shared_ptr (new GammaTransferFunction (2.2)) + ); + +ColourConversion ColourConversion::rec709_to_xyz ( + shared_ptr (new ModifiedGammaTransferFunction (2.4, 0.081, 0.099, 4.5)), + dcp::colour_matrix::srgb_to_xyz, + shared_ptr (new GammaTransferFunction (2.6)) + ); + +ColourConversion::ColourConversion ( + shared_ptr in, + double const matrix[3][3], + shared_ptr out + ) + : _in (in) + , _matrix (3, 3) + , _out (out) +{ + for (int i = 0; i < 3; ++i) { + for (int j = 0; j < 3; ++j) { + _matrix (i, j) = matrix[i][j]; + } + } +} + +bool +ColourConversion::about_equal (ColourConversion const & other, float epsilon) const +{ + for (int i = 0; i < 3; ++i) { + for (int j = 0; j < 3; ++j) { + if (fabs (_matrix(i, j) - other._matrix(i, j)) > epsilon) { + return false; + } + } + } + + return _in->about_equal (other._in, epsilon) && _out->about_equal (other._out, epsilon); +} -- cgit v1.2.3