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/* the Music Player Daemon (MPD)
* Copyright (C) 2003-2007 by Warren Dukes (warren.dukes@gmail.com)
* Copyright (C) 2008 Max Kellermann <max@duempel.org>
* 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
*/
#include "pcm_resample.h"
#include "gcc.h"
/* resampling code blatantly ripped from ESD */
size_t
pcm_resample_16(uint8_t channels,
unsigned src_rate,
const int16_t *src_buffer, mpd_unused size_t src_size,
unsigned dest_rate,
int16_t *dest_buffer, size_t dest_size,
mpd_unused struct pcm_resample_state *state)
{
unsigned src_pos, dest_pos = 0;
unsigned dest_samples = dest_size / 2;
int16_t lsample, rsample;
switch (channels) {
case 1:
while (dest_pos < dest_samples) {
src_pos = dest_pos * src_rate / dest_rate;
lsample = src_buffer[src_pos++];
dest_buffer[dest_pos++] = lsample;
}
break;
case 2:
while (dest_pos < dest_samples) {
src_pos = dest_pos * src_rate / dest_rate;
src_pos &= ~1;
lsample = src_buffer[src_pos++];
rsample = src_buffer[src_pos++];
dest_buffer[dest_pos++] = lsample;
dest_buffer[dest_pos++] = rsample;
}
break;
}
return dest_size;
}
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