1*600f14f4SXin Li /* 2*600f14f4SXin Li * ReplayGainAnalysis - analyzes input samples and give the recommended dB change 3*600f14f4SXin Li * Copyright (C) 2001 David Robinson and Glen Sawyer 4*600f14f4SXin Li * 5*600f14f4SXin Li * This library is free software; you can redistribute it and/or 6*600f14f4SXin Li * modify it under the terms of the GNU Lesser General Public 7*600f14f4SXin Li * License as published by the Free Software Foundation; either 8*600f14f4SXin Li * version 2.1 of the License, or (at your option) any later version. 9*600f14f4SXin Li * 10*600f14f4SXin Li * This library is distributed in the hope that it will be useful, 11*600f14f4SXin Li * but WITHOUT ANY WARRANTY; without even the implied warranty of 12*600f14f4SXin Li * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13*600f14f4SXin Li * Lesser General Public License for more details. 14*600f14f4SXin Li * 15*600f14f4SXin Li * You should have received a copy of the GNU Lesser General Public 16*600f14f4SXin Li * License along with this library; if not, write to the Free Software 17*600f14f4SXin Li * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 18*600f14f4SXin Li * 19*600f14f4SXin Li * concept and filter values by David Robinson ([email protected]) 20*600f14f4SXin Li * -- blame him if you think the idea is flawed 21*600f14f4SXin Li * coding by Glen Sawyer ([email protected]) 442 N 700 E, Provo, UT 84606 USA 22*600f14f4SXin Li * -- blame him if you think this runs too slowly, or the coding is otherwise flawed 23*600f14f4SXin Li * minor cosmetic tweaks to integrate with FLAC by Josh Coalson 24*600f14f4SXin Li * 25*600f14f4SXin Li * For an explanation of the concepts and the basic algorithms involved, go to: 26*600f14f4SXin Li * http://www.replaygain.org/ 27*600f14f4SXin Li */ 28*600f14f4SXin Li 29*600f14f4SXin Li #ifndef GAIN_ANALYSIS_H 30*600f14f4SXin Li #define GAIN_ANALYSIS_H 31*600f14f4SXin Li 32*600f14f4SXin Li #include <stddef.h> 33*600f14f4SXin Li 34*600f14f4SXin Li #define GAIN_NOT_ENOUGH_SAMPLES -24601 35*600f14f4SXin Li #define GAIN_ANALYSIS_ERROR 0 36*600f14f4SXin Li #define GAIN_ANALYSIS_OK 1 37*600f14f4SXin Li 38*600f14f4SXin Li #define INIT_GAIN_ANALYSIS_ERROR 0 39*600f14f4SXin Li #define INIT_GAIN_ANALYSIS_OK 1 40*600f14f4SXin Li 41*600f14f4SXin Li #ifdef __cplusplus 42*600f14f4SXin Li extern "C" { 43*600f14f4SXin Li #endif 44*600f14f4SXin Li 45*600f14f4SXin Li typedef float flac_float_t; /* Type used for filtering */ 46*600f14f4SXin Li 47*600f14f4SXin Li extern flac_float_t ReplayGainReferenceLoudness; /* in dB SPL, currently == 89.0 */ 48*600f14f4SXin Li 49*600f14f4SXin Li int InitGainAnalysis ( long samplefreq ); 50*600f14f4SXin Li int ValidGainFrequency ( long samplefreq ); 51*600f14f4SXin Li int AnalyzeSamples ( const flac_float_t* left_samples, const flac_float_t* right_samples, size_t num_samples, int num_channels ); 52*600f14f4SXin Li flac_float_t GetTitleGain ( void ); 53*600f14f4SXin Li flac_float_t GetAlbumGain ( void ); 54*600f14f4SXin Li 55*600f14f4SXin Li #ifdef __cplusplus 56*600f14f4SXin Li } 57*600f14f4SXin Li #endif 58*600f14f4SXin Li 59*600f14f4SXin Li #endif /* GAIN_ANALYSIS_H */ 60