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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[] = {
[0] = "FL", /* front left */
[1] = "FR", /* front right */
[2] = "FC", /* front center */
[3] = "LFE", /* low frequency */
[4] = "BL", /* back left */
[5] = "BR", /* back right */
[6] = "FLC", /* front left-of-center */
[7] = "FRC", /* front right-of-center */
[8] = "BC", /* back-center */
[9] = "SL", /* side left */
[10] = "SR", /* side right */
[11] = "TC", /* top center */
[12] = "TFL", /* top front left */
[13] = "TFC", /* top front center */
[14] = "TFR", /* top front right */
[15] = "TBL", /* top back left */
[16] = "TBC", /* top back center */
[17] = "TBR", /* top back right */
[29] = "DL", /* downmix left */
[30] = "DR", /* downmix right */
};
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;
uint64_t layout;
} channel_layout_map[] = {
{ "mono", 1, AV_CH_LAYOUT_MONO },
{ "stereo", 2, AV_CH_LAYOUT_STEREO },
{ "2.1", 3, AV_CH_LAYOUT_2POINT1 },
{ "4.0", 4, AV_CH_LAYOUT_4POINT0 },
{ "quad", 4, AV_CH_LAYOUT_QUAD },
{ "5.0", 5, AV_CH_LAYOUT_5POINT0_BACK },
{ "5.0(side)", 5, AV_CH_LAYOUT_5POINT0 },
{ "5.1", 6, AV_CH_LAYOUT_5POINT1_BACK },
{ "5.1(side)", 6, AV_CH_LAYOUT_5POINT1 },
{ "7.1", 8, AV_CH_LAYOUT_7POINT1 },
{ "7.1(wide)", 8, AV_CH_LAYOUT_7POINT1_WIDE },
{ "downmix", 2, AV_CH_LAYOUT_STEREO_DOWNMIX, },
{ 0 }
};
static uint64_t get_channel_layout_single(const char *name, int name_len)
{
int i;
char *end;
int64_t layout;
for (i = 0; i < FF_ARRAY_ELEMS(channel_layout_map) - 1; i++) {
if (strlen(channel_layout_map[i].name) == name_len &&
!memcmp(channel_layout_map[i].name, name, name_len))
return channel_layout_map[i].layout;
}
for (i = 0; i < FF_ARRAY_ELEMS(channel_names); i++)
if (channel_names[i] &&
strlen(channel_names[i]) == name_len &&
!memcmp(channel_names[i], name, name_len))
return (int64_t)1 << i;
i = strtol(name, &end, 10);
if (end - name == name_len ||
(end + 1 - name == name_len && *end == 'c'))
return av_get_default_channel_layout(i);
layout = strtoll(name, &end, 0);
if (end - name == name_len)
return FFMAX(layout, 0);
return 0;
}
uint64_t av_get_channel_layout(const char *name)
{
const char *n, *e;
const char *name_end = name + strlen(name);
int64_t layout = 0, layout_single;
for (n = name; n < name_end; n = e + 1) {
for (e = n; e < name_end && *e != '+' && *e != '|'; e++);
layout_single = get_channel_layout_single(n, e - n);
if (!layout_single)
return 0;
layout |= layout_single;
}
return layout;
}
void av_get_channel_layout_string(char *buf, int buf_size,
int nb_channels, uint64_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 & (UINT64_C(1) << 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(uint64_t channel_layout)
{
int count;
uint64_t x = channel_layout;
for (count = 0; x; count++)
x &= x-1; // unset lowest set bit
return count;
}
int64_t av_get_default_channel_layout(int nb_channels) {
int i;
for (i = 0; channel_layout_map[i].name; i++)
if (nb_channels == channel_layout_map[i].nb_channels)
return channel_layout_map[i].layout;
return 0;
}
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