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/*
* Copyright (C) 2003-2011 The Music Player Daemon Project
* 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.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#ifndef PCM_MIX_H
#define PCM_MIX_H
#include "audio_format.h"
#include <stdbool.h>
#include <stddef.h>
#include <libavutil/samplefmt.h>
/*
* Linearly mixes two PCM buffers. Both must have the same length and
* the same audio format. The formula is:
*
* s1 := s1 * portion1 + s2 * (1 - portion1)
*
* @param buffer1 the first PCM buffer, and the destination buffer
* @param buffer2 the second PCM buffer
* @param size the size of both buffers in bytes
* @param format the sample format of both buffers
* @param portion1 a number between 0.0 and 1.0 specifying the portion
* of the first buffer in the mix; portion2 = (1.0 - portion1). The value
* NaN is used by the MixRamp code to specify that simple addition is required.
*
* @return true on success, false if the format is not supported
*/
bool pcm_mix(void *buffer1, const void *buffer2, size_t size,
enum AVSampleFormat format, float portion1);
#endif
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