mpd/src/pcm_mix.c
Avuton Olrich 0aee49bdf8 all: Update copyright header.
This updates the copyright header to all be the same, which is
pretty much an update of where to mail request for a copy of the GPL
and the years of the MPD project. This also puts all committers under
'The Music Player Project' umbrella. These entries should go
individually in the AUTHORS file, for consistancy.
2009-03-13 11:51:55 -07:00

123 lines
3.0 KiB
C

/*
* Copyright (C) 2003-2009 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.
*/
#include "pcm_mix.h"
#include "pcm_volume.h"
#include "pcm_utils.h"
#include "audio_format.h"
#include <glib.h>
#include <math.h>
#undef G_LOG_DOMAIN
#define G_LOG_DOMAIN "pcm"
static void
pcm_add_8(int8_t *buffer1, const int8_t *buffer2,
unsigned num_samples, int volume1, int volume2)
{
while (num_samples > 0) {
int32_t sample1 = *buffer1;
int32_t sample2 = *buffer2++;
sample1 = ((sample1 * volume1 + sample2 * volume2) +
pcm_volume_dither() + PCM_VOLUME_1 / 2)
/ PCM_VOLUME_1;
*buffer1++ = pcm_range(sample1, 8);
--num_samples;
}
}
static void
pcm_add_16(int16_t *buffer1, const int16_t *buffer2,
unsigned num_samples, int volume1, int volume2)
{
while (num_samples > 0) {
int32_t sample1 = *buffer1;
int32_t sample2 = *buffer2++;
sample1 = ((sample1 * volume1 + sample2 * volume2) +
pcm_volume_dither() + PCM_VOLUME_1 / 2)
/ PCM_VOLUME_1;
*buffer1++ = pcm_range(sample1, 16);
--num_samples;
}
}
static void
pcm_add_24(int32_t *buffer1, const int32_t *buffer2,
unsigned num_samples, unsigned volume1, unsigned volume2)
{
while (num_samples > 0) {
int64_t sample1 = *buffer1;
int64_t sample2 = *buffer2++;
sample1 = ((sample1 * volume1 + sample2 * volume2) +
pcm_volume_dither() + PCM_VOLUME_1 / 2)
/ PCM_VOLUME_1;
*buffer1++ = pcm_range(sample1, 24);
--num_samples;
}
}
static void
pcm_add(void *buffer1, const void *buffer2, size_t size,
int vol1, int vol2,
const struct audio_format *format)
{
switch (format->bits) {
case 8:
pcm_add_8((int8_t *)buffer1, (const int8_t *)buffer2,
size, vol1, vol2);
break;
case 16:
pcm_add_16((int16_t *)buffer1, (const int16_t *)buffer2,
size / 2, vol1, vol2);
break;
case 24:
pcm_add_24((int32_t*)buffer1,
(const int32_t*)buffer2,
size / 4, vol1, vol2);
break;
default:
g_error("%u bits not supported by pcm_add!\n", format->bits);
}
}
void
pcm_mix(void *buffer1, const void *buffer2, size_t size,
const struct audio_format *format, float portion1)
{
int vol1;
float s = sin(M_PI_2 * portion1);
s *= s;
vol1 = s * PCM_VOLUME_1 + 0.5;
vol1 = vol1 > PCM_VOLUME_1 ? PCM_VOLUME_1 : (vol1 < 0 ? 0 : vol1);
pcm_add(buffer1, buffer2, size, vol1, PCM_VOLUME_1 - vol1, format);
}