2 Copyright (C) 2012-2014 Carl Hetherington <cth@carlh.net>
4 This file is part of libdcp.
6 libdcp is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
11 libdcp is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with libdcp. If not, see <http://www.gnu.org/licenses/>.
20 /** @file src/transfer_function.h
21 * @brief TransferFunction class.
24 #ifndef LIBDCP_TRANSFER_FUNCTION_H
25 #define LIBDCP_TRANSFER_FUNCTION_H
27 #include <boost/noncopyable.hpp>
28 #include <boost/shared_ptr.hpp>
29 #include <boost/thread/mutex.hpp>
34 /** @class TransferFunction
35 * @brief A transfer function represented by a lookup table.
37 class TransferFunction : public boost::noncopyable
40 virtual ~TransferFunction ();
42 /** @return A look-up table (of size 2^bit_depth) whose values range from 0 to 1 */
43 double const * lut (int bit_depth, bool inverse) const;
45 virtual bool about_equal (boost::shared_ptr<const TransferFunction> other, double epsilon) const = 0;
48 /** Make a LUT and return an array allocated by new */
49 virtual double * make_lut (int bit_depth, bool inverse) const = 0;
52 mutable std::map<std::pair<int, bool>, double*> _luts;
53 /** mutex to protect _luts */
54 mutable boost::mutex _mutex;