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/* ScummVM - Graphic Adventure Engine
*
* ScummVM is the legal property of its developers, whose names
* are too numerous to list here. Please refer to the COPYRIGHT
* file distributed with this source distribution.
*
* 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
*/
#ifndef AUDIO_RATE_H
#define AUDIO_RATE_H
#include "common/scummsys.h"
namespace Audio {
class AudioStream;
typedef int16 st_sample_t;
typedef uint16 st_volume_t;
typedef uint32 st_size_t;
typedef uint32 st_rate_t;
/* Minimum and maximum values a sample can hold. */
enum {
ST_SAMPLE_MAX = 0x7fffL,
ST_SAMPLE_MIN = (-ST_SAMPLE_MAX - 1L)
};
enum {
ST_EOF = -1,
ST_SUCCESS = 0
};
static inline void clampedAdd(int16& a, int b) {
int val;
#ifdef OUTPUT_UNSIGNED_AUDIO
val = (a ^ 0x8000) + b;
#else
val = a + b;
#endif
if (val > ST_SAMPLE_MAX)
val = ST_SAMPLE_MAX;
else if (val < ST_SAMPLE_MIN)
val = ST_SAMPLE_MIN;
#ifdef OUTPUT_UNSIGNED_AUDIO
a = ((int16)val) ^ 0x8000;
#else
a = val;
#endif
}
class RateConverter {
public:
RateConverter() {}
virtual ~RateConverter() {}
/**
* @return Number of sample pairs written into the buffer.
*/
virtual int flow(AudioStream &input, st_sample_t *obuf, st_size_t osamp, st_volume_t vol_l, st_volume_t vol_r) = 0;
virtual int drain(st_sample_t *obuf, st_size_t osamp, st_volume_t vol) = 0;
};
RateConverter *makeRateConverter(st_rate_t inrate, st_rate_t outrate, bool stereo, bool reverseStereo = false);
} // End of namespace Audio
#endif
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