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/*
* Copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* audio conversion routines
*/
#include "avstring.h"
#include "avutil.h"
#include "audioconvert.h"
static const char * const channel_names[] = {
"FL", "FR", "FC", "LFE", "BL", "BR", "FLC", "FRC",
"BC", "SL", "SR", "TC", "TFL", "TFC", "TFR", "TBL",
"TBC", "TBR",
[29] = "DL",
[30] = "DR",
};
static const char *get_channel_name(int channel_id)
{
if (channel_id < 0 || channel_id >= FF_ARRAY_ELEMS(channel_names))
return NULL;
return channel_names[channel_id];
}
static const struct {
const char *name;
int nb_channels;
int64_t layout;
} channel_layout_map[] = {
{ "mono", 1, AV_CH_LAYOUT_MONO },
{ "stereo", 2, AV_CH_LAYOUT_STEREO },
{ "4.0", 4, AV_CH_LAYOUT_4POINT0 },
{ "quad", 4, AV_CH_LAYOUT_QUAD },
{ "5.0", 5, AV_CH_LAYOUT_5POINT0 },
{ "5.0(back)", 5, AV_CH_LAYOUT_5POINT0_BACK },
{ "5.1", 6, AV_CH_LAYOUT_5POINT1 },
{ "5.1(back)", 6, AV_CH_LAYOUT_5POINT1_BACK },
{ "5.1+downmix", 8, AV_CH_LAYOUT_5POINT1|AV_CH_LAYOUT_STEREO_DOWNMIX, },
{ "7.1", 8, AV_CH_LAYOUT_7POINT1 },
{ "7.1(wide)", 8, AV_CH_LAYOUT_7POINT1_WIDE },
{ "7.1+downmix", 10, AV_CH_LAYOUT_7POINT1|AV_CH_LAYOUT_STEREO_DOWNMIX, },
{ 0 }
};
int64_t av_get_channel_layout(const char *name)
{
int i = 0;
do {
if (!strcmp(channel_layout_map[i].name, name))
return channel_layout_map[i].layout;
i++;
} while (channel_layout_map[i].name);
return 0;
}
void av_get_channel_layout_string(char *buf, int buf_size,
int nb_channels, int64_t channel_layout)
{
int i;
if (nb_channels <= 0)
nb_channels = av_get_channel_layout_nb_channels(channel_layout);
for (i = 0; channel_layout_map[i].name; i++)
if (nb_channels == channel_layout_map[i].nb_channels &&
channel_layout == channel_layout_map[i].layout) {
av_strlcpy(buf, channel_layout_map[i].name, buf_size);
return;
}
snprintf(buf, buf_size, "%d channels", nb_channels);
if (channel_layout) {
int i,ch;
av_strlcat(buf, " (", buf_size);
for(i=0,ch=0; i<64; i++) {
if ((channel_layout & (1L<<i))) {
const char *name = get_channel_name(i);
if (name) {
if (ch>0) av_strlcat(buf, "|", buf_size);
av_strlcat(buf, name, buf_size);
}
ch++;
}
}
av_strlcat(buf, ")", buf_size);
}
}
int av_get_channel_layout_nb_channels(int64_t channel_layout)
{
int count;
uint64_t x = channel_layout;
for (count = 0; x; count++)
x &= x-1; // unset lowest set bit
return count;
}
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