| /* |
| * ReplayGainAnalysis - analyzes input samples and give the recommended dB change |
| * Copyright (C) 2001 David Robinson and Glen Sawyer |
| * |
| * This library is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Lesser General Public |
| * License as published by the Free Software Foundation; either |
| * version 2.1 of the License, or (at your option) any later version. |
| * |
| * This library 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 |
| * Lesser General Public License for more details. |
| * |
| * You should have received a copy of the GNU Lesser General Public |
| * License along with this library; if not, write to the Free Software |
| * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| * |
| * concept and filter values by David Robinson (David@Robinson.org) |
| * -- blame him if you think the idea is flawed |
| * coding by Glen Sawyer (mp3gain@hotmail.com) 735 W 255 N, Orem, UT 84057-4505 USA |
| * -- blame him if you think this runs too slowly, or the coding is otherwise flawed |
| * |
| * For an explanation of the concepts and the basic algorithms involved, go to: |
| * http://www.replaygain.org/ |
| */ |
| |
| #ifndef GAIN_ANALYSIS_H |
| #define GAIN_ANALYSIS_H |
| |
| #ifdef HAVE_INTTYPES_H |
| # include <inttypes.h> |
| #else |
| # ifdef HAVE_STDINT_H |
| # include <stdint.h> |
| # endif |
| #endif |
| |
| #ifdef __cplusplus |
| extern "C" { |
| #endif |
| |
| |
| typedef sample_t Float_t; /* Type used for filtering */ |
| |
| |
| #define PINK_REF 64.82 /* 298640883795 */ /* calibration value for 89dB */ |
| |
| |
| #define YULE_ORDER 10 |
| #define BUTTER_ORDER 2 |
| #define YULE_FILTER filterYule |
| #define BUTTER_FILTER filterButter |
| #define RMS_PERCENTILE 0.95 /* percentile which is louder than the proposed level */ |
| #define MAX_SAMP_FREQ 48000L /* maximum allowed sample frequency [Hz] */ |
| #define RMS_WINDOW_TIME_NUMERATOR 1L |
| #define RMS_WINDOW_TIME_DENOMINATOR 20L /* numerator / denominator = time slice size [s] */ |
| #define STEPS_per_dB 100. /* Table entries per dB */ |
| #define MAX_dB 120. /* Table entries for 0...MAX_dB (normal max. values are 70...80 dB) */ |
| |
| enum { GAIN_NOT_ENOUGH_SAMPLES = -24601, GAIN_ANALYSIS_ERROR = 0, GAIN_ANALYSIS_OK = |
| 1, INIT_GAIN_ANALYSIS_ERROR = 0, INIT_GAIN_ANALYSIS_OK = 1 |
| }; |
| |
| enum { MAX_ORDER = (BUTTER_ORDER > YULE_ORDER ? BUTTER_ORDER : YULE_ORDER) |
| , MAX_SAMPLES_PER_WINDOW = ((MAX_SAMP_FREQ * RMS_WINDOW_TIME_NUMERATOR) / RMS_WINDOW_TIME_DENOMINATOR + 1) /* max. Samples per Time slice */ |
| }; |
| |
| struct replaygain_data { |
| Float_t linprebuf[MAX_ORDER * 2]; |
| Float_t *linpre; /* left input samples, with pre-buffer */ |
| Float_t lstepbuf[MAX_SAMPLES_PER_WINDOW + MAX_ORDER]; |
| Float_t *lstep; /* left "first step" (i.e. post first filter) samples */ |
| Float_t loutbuf[MAX_SAMPLES_PER_WINDOW + MAX_ORDER]; |
| Float_t *lout; /* left "out" (i.e. post second filter) samples */ |
| Float_t rinprebuf[MAX_ORDER * 2]; |
| Float_t *rinpre; /* right input samples ... */ |
| Float_t rstepbuf[MAX_SAMPLES_PER_WINDOW + MAX_ORDER]; |
| Float_t *rstep; |
| Float_t routbuf[MAX_SAMPLES_PER_WINDOW + MAX_ORDER]; |
| Float_t *rout; |
| long sampleWindow; /* number of samples required to reach number of milliseconds required for RMS window */ |
| long totsamp; |
| double lsum; |
| double rsum; |
| int freqindex; |
| int first; |
| uint32_t A[(size_t) (STEPS_per_dB * MAX_dB)]; |
| uint32_t B[(size_t) (STEPS_per_dB * MAX_dB)]; |
| |
| }; |
| #ifndef replaygain_data_defined |
| #define replaygain_data_defined |
| typedef struct replaygain_data replaygain_t; |
| #endif |
| |
| |
| |
| |
| int InitGainAnalysis(replaygain_t * rgData, long samplefreq); |
| int AnalyzeSamples(replaygain_t * rgData, const Float_t * left_samples, |
| const Float_t * right_samples, size_t num_samples, int num_channels); |
| int ResetSampleFrequency(replaygain_t * rgData, long samplefreq); |
| Float_t GetTitleGain(replaygain_t * rgData); |
| Float_t GetAlbumGain(replaygain_t * rgData); |
| |
| |
| #ifdef __cplusplus |
| } |
| #endif |
| #endif /* GAIN_ANALYSIS_H */ |