flac/src/plugin_common/replaygain_synthesis.h

/* plugin_common - Routines common to several plugins
 * Copyright (C) 2002,2003  Josh Coalson
 *
 * 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., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 */

#ifndef FLAC__PLUGIN_COMMON__REPLAYGAIN_SYNTHESIS_H
#define FLAC__PLUGIN_COMMON__REPLAYGAIN_SYNTHESIS_H

#include "defs.h"
#include "FLAC/ordinals.h"

typedef enum {
	NOISE_SHAPING_NONE = 0,
	NOISE_SHAPING_LOW = 1,
	NOISE_SHAPING_MEDUIM = 2,
	NOISE_SHAPING_HIGH = 3
} NoiseShaping;

typedef struct {
	const float*  FilterCoeff;
	FLAC__uint64  Mask;
	double        Add;
	float         Dither;
	float         ErrorHistory     [FLAC_PLUGIN__MAX_SUPPORTED_CHANNELS] [16];  /* 16th order Noise shaping */
	float         DitherHistory    [FLAC_PLUGIN__MAX_SUPPORTED_CHANNELS] [16];
	int           LastRandomNumber [FLAC_PLUGIN__MAX_SUPPORTED_CHANNELS];
	unsigned      LastHistoryIndex;
	NoiseShaping  ShapingType;
} DitherContext;

void FLAC__plugin_common__init_dither_context(DitherContext *dither, int bits, int shapingtype);

/* scale = (float) pow(10., (double)replaygain * 0.05); */
int FLAC__plugin_common__apply_gain(FLAC__byte *data_out, FLAC__bool little_endian_data_out, const FLAC__int32 * const input[], unsigned wide_samples, unsigned channels, const unsigned source_bps, const unsigned target_bps, const float scale, const FLAC__bool hard_limit, FLAC__bool do_dithering, DitherContext *dither_context);

#endif