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/* the Music Player Daemon (MPD)
* Copyright (C) 2003-2007 by Warren Dukes (warren.dukes@gmail.com)
* This project's homepage is: http://www.musicpd.org
*
* 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 MPD_PCM_UTILS_H
#define MPD_PCM_UTILS_H
#include "pcm_resample.h"
#include "pcm_dither.h"
#include <glib.h>
#include <stdint.h>
#include <stddef.h>
struct audio_format;
enum {
/** this value means "100% volume" */
PCM_VOLUME_1 = 1000,
};
struct pcm_convert_state {
struct pcm_resample_state resample;
struct pcm_dither_24 dither;
/* Strict C99 doesn't allow empty structs */
int error;
};
/**
* Check if the value is within the range of the provided bit size,
* and caps it if necessary.
*/
static inline int32_t
pcm_range(int32_t sample, unsigned bits)
{
if (G_UNLIKELY(sample < (-1 << (bits - 1))))
return -1 << (bits - 1);
if (G_UNLIKELY(sample >= (1 << (bits - 1))))
return (1 << (bits - 1)) - 1;
return sample;
}
/**
* Converts a float value (0.0 = silence, 1.0 = 100% volume) to an
* integer volume value (1000 = 100%).
*/
static inline int
pcm_float_to_volume(float volume)
{
return volume * PCM_VOLUME_1 + 0.5;
}
void pcm_volume(char *buffer, int bufferSize,
const struct audio_format *format,
int volume);
void pcm_mix(char *buffer1, const char *buffer2, size_t size,
const struct audio_format *format, float portion1);
void pcm_convert_init(struct pcm_convert_state *state);
size_t pcm_convert(const struct audio_format *inFormat,
const char *inBuffer, size_t inSize,
const struct audio_format *outFormat,
char *outBuffer,
struct pcm_convert_state *convState);
size_t pcm_convert_size(const struct audio_format *inFormat, size_t inSize,
const struct audio_format *outFormat);
#endif
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