/////////////////////////////////////////////////////////////////////////////////// // Copyright (C) 2012 maintech GmbH, Otto-Hahn-Str. 15, 97204 Hoechberg, Germany // // written by Christian Daniel // // Copyright (C) 2015-2016, 2018-2019 Edouard Griffiths, F4EXB // // // // 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 as version 3 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 V3 for more details. // // // // You should have received a copy of the GNU General Public License // // along with this program. If not, see . // /////////////////////////////////////////////////////////////////////////////////// #ifndef SDRBASE_AUDIO_AUDIOCOMPRESSOR_H_ #define SDRBASE_AUDIO_AUDIOCOMPRESSOR_H_ #include #include "export.h" class SDRBASE_API AudioCompressor { public: AudioCompressor(); ~AudioCompressor(); void fillLUT(); //!< 4 bands void fillLUT2(); //!< 8 bands (default) void fillALaw(); //!< A-law compression to 8 bits void fillULaw(); //!< u-law compression to 8 bits int16_t compress(int16_t sample); int8_t compress8(int16_t sample); private: int8_t ALaw_Encode(int16_t number); int8_t MuLaw_Encode(int16_t number); int16_t m_lut[32768]; static const uint16_t ALAW_MAX; static const uint16_t MULAW_MAX; static const uint16_t MULAW_BIAS; }; #endif /* SDRBASE_AUDIO_AUDIOCOMPRESSOR_H_ */