RepoMirrors
/
ffmpeg
mirror of https://git.ffmpeg.org/ffmpeg.git
1
0
Fork 0
Code Issues Projects Releases Wiki Activity
ffmpeg/libavutil/channel_layout.c

817 lines
26 KiB
C
Raw Blame History

/*
* 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 channel layout utility functions
*/
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include "channel_layout.h"
#include "bprint.h"
#include "common.h"
#include "error.h"
#include "macros.h"
#include "opt.h"
struct channel_name {
const char *name;
const char *description;
};
static const struct channel_name channel_names[] = {
[AV_CHAN_FRONT_LEFT ] = { "FL", "front left" },
[AV_CHAN_FRONT_RIGHT ] = { "FR", "front right" },
[AV_CHAN_FRONT_CENTER ] = { "FC", "front center" },
[AV_CHAN_LOW_FREQUENCY ] = { "LFE", "low frequency" },
[AV_CHAN_BACK_LEFT ] = { "BL", "back left" },
[AV_CHAN_BACK_RIGHT ] = { "BR", "back right" },
[AV_CHAN_FRONT_LEFT_OF_CENTER ] = { "FLC", "front left-of-center" },
[AV_CHAN_FRONT_RIGHT_OF_CENTER] = { "FRC", "front right-of-center" },
[AV_CHAN_BACK_CENTER ] = { "BC", "back center" },
[AV_CHAN_SIDE_LEFT ] = { "SL", "side left" },
[AV_CHAN_SIDE_RIGHT ] = { "SR", "side right" },
[AV_CHAN_TOP_CENTER ] = { "TC", "top center" },
[AV_CHAN_TOP_FRONT_LEFT ] = { "TFL", "top front left" },
[AV_CHAN_TOP_FRONT_CENTER ] = { "TFC", "top front center" },
[AV_CHAN_TOP_FRONT_RIGHT ] = { "TFR", "top front right" },
[AV_CHAN_TOP_BACK_LEFT ] = { "TBL", "top back left" },
[AV_CHAN_TOP_BACK_CENTER ] = { "TBC", "top back center" },
[AV_CHAN_TOP_BACK_RIGHT ] = { "TBR", "top back right" },
[AV_CHAN_STEREO_LEFT ] = { "DL", "downmix left" },
[AV_CHAN_STEREO_RIGHT ] = { "DR", "downmix right" },
[AV_CHAN_WIDE_LEFT ] = { "WL", "wide left" },
[AV_CHAN_WIDE_RIGHT ] = { "WR", "wide right" },
[AV_CHAN_SURROUND_DIRECT_LEFT ] = { "SDL", "surround direct left" },
[AV_CHAN_SURROUND_DIRECT_RIGHT] = { "SDR", "surround direct right" },
[AV_CHAN_LOW_FREQUENCY_2 ] = { "LFE2", "low frequency 2" },
[AV_CHAN_TOP_SIDE_LEFT ] = { "TSL", "top side left" },
[AV_CHAN_TOP_SIDE_RIGHT ] = { "TSR", "top side right" },
[AV_CHAN_BOTTOM_FRONT_CENTER ] = { "BFC", "bottom front center" },
[AV_CHAN_BOTTOM_FRONT_LEFT ] = { "BFL", "bottom front left" },
[AV_CHAN_BOTTOM_FRONT_RIGHT ] = { "BFR", "bottom front right" },
};
static const char *get_channel_name(enum AVChannel channel_id)
{
if ((unsigned) channel_id >= FF_ARRAY_ELEMS(channel_names) ||
!channel_names[channel_id].name)
return NULL;
return channel_names[channel_id].name;
}
void av_channel_name_bprint(AVBPrint *bp, enum AVChannel channel_id)
{
if ((unsigned)channel_id < FF_ARRAY_ELEMS(channel_names))
av_bprintf(bp, "%s", channel_names[channel_id].name);
else if (channel_id == AV_CHAN_NONE)
av_bprintf(bp, "NONE");
else
av_bprintf(bp, "USR%d", channel_id);
}
int av_channel_name(char *buf, size_t buf_size, enum AVChannel channel_id)
{
AVBPrint bp;
if (!buf && buf_size)
return AVERROR(EINVAL);
av_bprint_init_for_buffer(&bp, buf, buf_size);
av_channel_name_bprint(&bp, channel_id);
return bp.len;
}
void av_channel_description_bprint(AVBPrint *bp, enum AVChannel channel_id)
{
if ((unsigned)channel_id < FF_ARRAY_ELEMS(channel_names))
av_bprintf(bp, "%s", channel_names[channel_id].description);
else
av_bprintf(bp, "user %d", channel_id);
}
int av_channel_description(char *buf, size_t buf_size, enum AVChannel channel_id)
{
AVBPrint bp;
if (!buf && buf_size)
return AVERROR(EINVAL);
av_bprint_init_for_buffer(&bp, buf, buf_size);
av_channel_description_bprint(&bp, channel_id);
return bp.len;
}
enum AVChannel av_channel_from_string(const char *str)
{
int i;
char *endptr = (char *)str;
enum AVChannel id = AV_CHAN_NONE;
for (i = 0; i < FF_ARRAY_ELEMS(channel_names); i++) {
if (channel_names[i].name && !strcmp(str, channel_names[i].name))
return i;
}
if (!strncmp(str, "USR", 3)) {
const char *p = str + 3;
id = strtol(p, &endptr, 0);
}
if (id >= 0 && !*endptr)
return id;
return AV_CHAN_NONE;
}
struct channel_layout_name {
const char *name;
AVChannelLayout layout;
};
static const struct channel_layout_name channel_layout_map[] = {
{ "mono", AV_CHANNEL_LAYOUT_MONO },
{ "stereo", AV_CHANNEL_LAYOUT_STEREO },
{ "stereo", AV_CHANNEL_LAYOUT_STEREO_DOWNMIX },
{ "2.1", AV_CHANNEL_LAYOUT_2POINT1 },
{ "3.0", AV_CHANNEL_LAYOUT_SURROUND },
{ "3.0(back)", AV_CHANNEL_LAYOUT_2_1 },
{ "4.0", AV_CHANNEL_LAYOUT_4POINT0 },
{ "quad", AV_CHANNEL_LAYOUT_QUAD },
{ "quad(side)", AV_CHANNEL_LAYOUT_2_2 },
{ "3.1", AV_CHANNEL_LAYOUT_3POINT1 },
{ "5.0", AV_CHANNEL_LAYOUT_5POINT0_BACK },
{ "5.0(side)", AV_CHANNEL_LAYOUT_5POINT0 },
{ "4.1", AV_CHANNEL_LAYOUT_4POINT1 },
{ "5.1", AV_CHANNEL_LAYOUT_5POINT1_BACK },
{ "5.1(side)", AV_CHANNEL_LAYOUT_5POINT1 },
{ "6.0", AV_CHANNEL_LAYOUT_6POINT0 },
{ "6.0(front)", AV_CHANNEL_LAYOUT_6POINT0_FRONT },
{ "hexagonal", AV_CHANNEL_LAYOUT_HEXAGONAL },
{ "6.1", AV_CHANNEL_LAYOUT_6POINT1 },
{ "6.1(back)", AV_CHANNEL_LAYOUT_6POINT1_BACK },
{ "6.1(front)", AV_CHANNEL_LAYOUT_6POINT1_FRONT },
{ "7.0", AV_CHANNEL_LAYOUT_7POINT0 },
{ "7.0(front)", AV_CHANNEL_LAYOUT_7POINT0_FRONT },
{ "7.1", AV_CHANNEL_LAYOUT_7POINT1 },
{ "7.1(wide)", AV_CHANNEL_LAYOUT_7POINT1_WIDE_BACK },
{ "7.1(wide-side)", AV_CHANNEL_LAYOUT_7POINT1_WIDE },
{ "octagonal", AV_CHANNEL_LAYOUT_OCTAGONAL },
{ "hexadecagonal", AV_CHANNEL_LAYOUT_HEXADECAGONAL },
{ "downmix", AV_CHANNEL_LAYOUT_STEREO_DOWNMIX, },
{ "22.2", AV_CHANNEL_LAYOUT_22POINT2, },
};
#if FF_API_OLD_CHANNEL_LAYOUT
FF_DISABLE_DEPRECATION_WARNINGS
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); 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.u.mask;
}
for (i = 0; i < FF_ARRAY_ELEMS(channel_names); i++)
if (channel_names[i].name &&
strlen(channel_names[i].name) == name_len &&
!memcmp(channel_names[i].name, name, name_len))
return (int64_t)1 << i;
errno = 0;
i = strtol(name, &end, 10);
if (!errno && (end + 1 - name == name_len && *end == 'c'))
return av_get_default_channel_layout(i);
errno = 0;
layout = strtoll(name, &end, 0);
if (!errno && 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;
}
int av_get_extended_channel_layout(const char *name, uint64_t* channel_layout, int* nb_channels)
{
int nb = 0;
char *end;
uint64_t layout = av_get_channel_layout(name);
if (layout) {
*channel_layout = layout;
*nb_channels = av_get_channel_layout_nb_channels(layout);
return 0;
}
nb = strtol(name, &end, 10);
if (!errno && *end == 'C' && *(end + 1) == '\0' && nb > 0 && nb < 64) {
*channel_layout = 0;
*nb_channels = nb;
return 0;
}
return AVERROR(EINVAL);
}
void av_bprint_channel_layout(struct AVBPrint *bp,
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; i < FF_ARRAY_ELEMS(channel_layout_map); i++)
if (nb_channels == channel_layout_map[i].layout.nb_channels &&
channel_layout == channel_layout_map[i].layout.u.mask) {
av_bprintf(bp, "%s", channel_layout_map[i].name);
return;
}
av_bprintf(bp, "%d channels", nb_channels);
if (channel_layout) {
int i, ch;
av_bprintf(bp, " (");
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_bprintf(bp, "+");
av_bprintf(bp, "%s", name);
}
ch++;
}
}
av_bprintf(bp, ")");
}
}
void av_get_channel_layout_string(char *buf, int buf_size,
int nb_channels, uint64_t channel_layout)
{
AVBPrint bp;
av_bprint_init_for_buffer(&bp, buf, buf_size);
av_bprint_channel_layout(&bp, nb_channels, channel_layout);
}
int av_get_channel_layout_nb_channels(uint64_t channel_layout)
{
return av_popcount64(channel_layout);
}
int64_t av_get_default_channel_layout(int nb_channels) {
int i;
for (i = 0; i < FF_ARRAY_ELEMS(channel_layout_map); i++)
if (nb_channels == channel_layout_map[i].layout.nb_channels)
return channel_layout_map[i].layout.u.mask;
return 0;
}
int av_get_channel_layout_channel_index(uint64_t channel_layout,
uint64_t channel)
{
if (!(channel_layout & channel) ||
av_get_channel_layout_nb_channels(channel) != 1)
return AVERROR(EINVAL);
channel_layout &= channel - 1;
return av_get_channel_layout_nb_channels(channel_layout);
}
const char *av_get_channel_name(uint64_t channel)
{
int i;
if (av_get_channel_layout_nb_channels(channel) != 1)
return NULL;
for (i = 0; i < 64; i++)
if ((1ULL<<i) & channel)
return get_channel_name(i);
return NULL;
}
const char *av_get_channel_description(uint64_t channel)
{
int i;
if (av_get_channel_layout_nb_channels(channel) != 1)
return NULL;
for (i = 0; i < FF_ARRAY_ELEMS(channel_names); i++)
if ((1ULL<<i) & channel)
return channel_names[i].description;
return NULL;
}
uint64_t av_channel_layout_extract_channel(uint64_t channel_layout, int index)
{
int i;
if (av_get_channel_layout_nb_channels(channel_layout) <= index)
return 0;
for (i = 0; i < 64; i++) {
if ((1ULL << i) & channel_layout && !index--)
return 1ULL << i;
}
return 0;
}
int av_get_standard_channel_layout(unsigned index, uint64_t *layout,
const char **name)
{
if (index >= FF_ARRAY_ELEMS(channel_layout_map))
return AVERROR_EOF;
if (layout) *layout = channel_layout_map[index].layout.u.mask;
if (name) *name = channel_layout_map[index].name;
return 0;
}
FF_ENABLE_DEPRECATION_WARNINGS
#endif
int av_channel_layout_from_mask(AVChannelLayout *channel_layout,
uint64_t mask)
{
if (!mask)
return AVERROR(EINVAL);
channel_layout->order = AV_CHANNEL_ORDER_NATIVE;
channel_layout->nb_channels = av_popcount64(mask);
channel_layout->u.mask = mask;
return 0;
}
int av_channel_layout_from_string(AVChannelLayout *channel_layout,
const char *str)
{
int i;
int channels = 0, nb_channels = 0, native = 1;
enum AVChannel highest_channel = AV_CHAN_NONE;
const char *dup;
char *chlist, *end;
uint64_t mask = 0;
/* channel layout names */
for (i = 0; i < FF_ARRAY_ELEMS(channel_layout_map); i++) {
if (channel_layout_map[i].name && !strcmp(str, channel_layout_map[i].name)) {
*channel_layout = channel_layout_map[i].layout;
return 0;
}
}
chlist = av_strdup(str);
if (!chlist)
return AVERROR(ENOMEM);
/* channel names */
av_sscanf(str, "%d channels (%[^)]", &nb_channels, chlist);
end = strchr(str, ')');
dup = chlist;
while (*dup) {
char *channel, *chname;
int ret = av_opt_get_key_value(&dup, "@", "+", AV_OPT_FLAG_IMPLICIT_KEY, &channel, &chname);
if (ret < 0) {
av_free(chlist);
return ret;
}
if (*dup)
dup++; // skip separator
if (channel && !*channel)
av_freep(&channel);
for (i = 0; i < FF_ARRAY_ELEMS(channel_names); i++) {
if (channel_names[i].name && !strcmp(channel ? channel : chname, channel_names[i].name)) {
if (channel || i < highest_channel || mask & (1ULL << i))
native = 0; // Not a native layout, use a custom one
highest_channel = i;
mask |= 1ULL << i;
break;
}
}
if (!channel && i >= FF_ARRAY_ELEMS(channel_names)) {
char *endptr = chname;
enum AVChannel id = AV_CHAN_NONE;
if (!strncmp(chname, "USR", 3)) {
const char *p = chname + 3;
id = strtol(p, &endptr, 0);
}
if (id < 0 || *endptr) {
native = 0; // Unknown channel name
channels = 0;
mask = 0;
av_free(chname);
break;
}
if (id > 63)
native = 0; // Not a native layout, use a custom one
else {
if (id < highest_channel || mask & (1ULL << id))
native = 0; // Not a native layout, use a custom one
highest_channel = id;
mask |= 1ULL << id;
}
}
channels++;
av_free(channel);
av_free(chname);
}
if (mask && native) {
av_free(chlist);
if (nb_channels && ((nb_channels != channels) || (!end || *++end)))
return AVERROR(EINVAL);
av_channel_layout_from_mask(channel_layout, mask);
return 0;
}
/* custom layout of channel names */
if (channels && !native) {
int idx = 0;
if (nb_channels && ((nb_channels != channels) || (!end || *++end))) {
av_free(chlist);
return AVERROR(EINVAL);
}
channel_layout->u.map = av_calloc(channels, sizeof(*channel_layout->u.map));
if (!channel_layout->u.map) {
av_free(chlist);
return AVERROR(ENOMEM);
}
channel_layout->order = AV_CHANNEL_ORDER_CUSTOM;
channel_layout->nb_channels = channels;
dup = chlist;
while (*dup) {
char *channel, *chname;
int ret = av_opt_get_key_value(&dup, "@", "+", AV_OPT_FLAG_IMPLICIT_KEY, &channel, &chname);
if (ret < 0) {
av_freep(&channel_layout->u.map);
av_free(chlist);
return ret;
}
if (*dup)
dup++; // skip separator
for (i = 0; i < FF_ARRAY_ELEMS(channel_names); i++) {
if (channel_names[i].name && !strcmp(channel ? channel : chname, channel_names[i].name)) {
channel_layout->u.map[idx].id = i;
if (channel)
av_strlcpy(channel_layout->u.map[idx].name, chname, sizeof(channel_layout->u.map[idx].name));
idx++;
break;
}
}
if (i >= FF_ARRAY_ELEMS(channel_names)) {
const char *p = (channel ? channel : chname) + 3;
channel_layout->u.map[idx].id = strtol(p, NULL, 0);
if (channel)
av_strlcpy(channel_layout->u.map[idx].name, chname, sizeof(channel_layout->u.map[idx].name));
idx++;
}
av_free(channel);
av_free(chname);
}
return 0;
}
av_freep(&chlist);
errno = 0;
mask = strtoull(str, &end, 0);
/* channel layout mask */
if (!errno && !*end && !strchr(str, '-') && mask) {
av_channel_layout_from_mask(channel_layout, mask);
return 0;
}
errno = 0;
channels = strtol(str, &end, 10);
/* number of channels */
if (!errno && !strcmp(end, "c") && channels > 0) {
av_channel_layout_default(channel_layout, channels);
if (channel_layout->order == AV_CHANNEL_ORDER_NATIVE)
return 0;
}
/* number of unordered channels */
if (!errno && (!strcmp(end, "C") || !strcmp(end, " channels"))
&& channels > 0) {
channel_layout->order = AV_CHANNEL_ORDER_UNSPEC;
channel_layout->nb_channels = channels;
return 0;
}
return AVERROR(EINVAL);
}
void av_channel_layout_uninit(AVChannelLayout *channel_layout)
{
if (channel_layout->order == AV_CHANNEL_ORDER_CUSTOM)
av_freep(&channel_layout->u.map);
memset(channel_layout, 0, sizeof(*channel_layout));
}
int av_channel_layout_copy(AVChannelLayout *dst, const AVChannelLayout *src)
{
av_channel_layout_uninit(dst);
*dst = *src;
if (src->order == AV_CHANNEL_ORDER_CUSTOM) {
dst->u.map = av_malloc_array(src->nb_channels, sizeof(*dst->u.map));
if (!dst->u.map)
return AVERROR(ENOMEM);
memcpy(dst->u.map, src->u.map, src->nb_channels * sizeof(*src->u.map));
}
return 0;
}
int av_channel_layout_describe_bprint(const AVChannelLayout *channel_layout,
AVBPrint *bp)
{
int i;
switch (channel_layout->order) {
case AV_CHANNEL_ORDER_NATIVE:
for (i = 0; i < FF_ARRAY_ELEMS(channel_layout_map); i++)
if (channel_layout->u.mask == channel_layout_map[i].layout.u.mask) {
av_bprintf(bp, "%s", channel_layout_map[i].name);
return 0;
}
// fall-through
case AV_CHANNEL_ORDER_CUSTOM:
if (channel_layout->nb_channels)
av_bprintf(bp, "%d channels (", channel_layout->nb_channels);
for (i = 0; i < channel_layout->nb_channels; i++) {
enum AVChannel ch = av_channel_layout_channel_from_index(channel_layout, i);
const char *channel = get_channel_name(ch);
if (i)
av_bprintf(bp, "+");
if (channel)
av_bprintf(bp, "%s", channel);
else
av_bprintf(bp, "USR%d", ch);
if (channel_layout->order == AV_CHANNEL_ORDER_CUSTOM &&
channel_layout->u.map[i].name[0])
av_bprintf(bp, "@%s", channel_layout->u.map[i].name);
}
if (channel_layout->nb_channels) {
av_bprintf(bp, ")");
return 0;
}
// fall-through
case AV_CHANNEL_ORDER_UNSPEC:
av_bprintf(bp, "%d channels", channel_layout->nb_channels);
return 0;
default:
return AVERROR(EINVAL);
}
}
int av_channel_layout_describe(const AVChannelLayout *channel_layout,
char *buf, size_t buf_size)
{
AVBPrint bp;
int ret;
if (!buf && buf_size)
return AVERROR(EINVAL);
av_bprint_init_for_buffer(&bp, buf, buf_size);
ret = av_channel_layout_describe_bprint(channel_layout, &bp);
if (ret < 0)
return ret;
return bp.len;
}
enum AVChannel
av_channel_layout_channel_from_index(const AVChannelLayout *channel_layout,
unsigned int idx)
{
int i;
if (idx >= channel_layout->nb_channels)
return AV_CHAN_NONE;
switch (channel_layout->order) {
case AV_CHANNEL_ORDER_CUSTOM:
return channel_layout->u.map[idx].id;
case AV_CHANNEL_ORDER_NATIVE:
for (i = 0; i < 64; i++) {
if ((1ULL << i) & channel_layout->u.mask && !idx--)
return i;
}
default:
return AV_CHAN_NONE;
}
}
enum AVChannel
av_channel_layout_channel_from_string(const AVChannelLayout *channel_layout,
const char *str)
{
int index = av_channel_layout_index_from_string(channel_layout, str);
if (index < 0)
return AV_CHAN_NONE;
return av_channel_layout_channel_from_index(channel_layout, index);
}
int av_channel_layout_index_from_channel(const AVChannelLayout *channel_layout,
enum AVChannel channel)
{
int i;
if (channel == AV_CHAN_NONE)
return AVERROR(EINVAL);
switch (channel_layout->order) {
case AV_CHANNEL_ORDER_CUSTOM:
for (i = 0; i < channel_layout->nb_channels; i++)
if (channel_layout->u.map[i].id == channel)
return i;
return AVERROR(EINVAL);
case AV_CHANNEL_ORDER_NATIVE: {
uint64_t mask = channel_layout->u.mask;
if ((unsigned)channel > 63 || !(mask & (1ULL << channel)))
return AVERROR(EINVAL);
mask &= (1ULL << channel) - 1;
return av_popcount64(mask);
}
default:
return AVERROR(EINVAL);
}
}
int av_channel_layout_index_from_string(const AVChannelLayout *channel_layout,
const char *str)
{
char *chname;
enum AVChannel ch = AV_CHAN_NONE;
switch (channel_layout->order) {
case AV_CHANNEL_ORDER_CUSTOM:
chname = strstr(str, "@");
if (chname) {
char buf[16];
chname++;
av_strlcpy(buf, str, FFMIN(sizeof(buf), chname - str));
if (!*chname)
chname = NULL;
ch = av_channel_from_string(buf);
if (ch == AV_CHAN_NONE && *buf)
return AVERROR(EINVAL);
}
for (int i = 0; chname && i < channel_layout->nb_channels; i++) {
if (!strcmp(chname, channel_layout->u.map[i].name) &&
(ch == AV_CHAN_NONE || ch == channel_layout->u.map[i].id))
return i;
}
// fall-through
case AV_CHANNEL_ORDER_NATIVE:
ch = av_channel_from_string(str);
if (ch == AV_CHAN_NONE)
return AVERROR(EINVAL);
return av_channel_layout_index_from_channel(channel_layout, ch);
}
return AVERROR(EINVAL);
}
int av_channel_layout_check(const AVChannelLayout *channel_layout)
{
if (channel_layout->nb_channels <= 0)
return 0;
switch (channel_layout->order) {
case AV_CHANNEL_ORDER_NATIVE:
return av_popcount64(channel_layout->u.mask) == channel_layout->nb_channels;
case AV_CHANNEL_ORDER_CUSTOM:
if (!channel_layout->u.map)
return 0;
for (int i = 0; i < channel_layout->nb_channels; i++) {
if (channel_layout->u.map[i].id == AV_CHAN_NONE)
return 0;
}
return 1;
case AV_CHANNEL_ORDER_UNSPEC:
return 1;
default:
return 0;
}
}
int av_channel_layout_compare(const AVChannelLayout *chl, const AVChannelLayout *chl1)
{
int i;
/* different channel counts -> not equal */
if (chl->nb_channels != chl1->nb_channels)
return 1;
/* if only one is unspecified -> not equal */
if ((chl->order == AV_CHANNEL_ORDER_UNSPEC) !=
(chl1->order == AV_CHANNEL_ORDER_UNSPEC))
return 1;
/* both are unspecified -> equal */
else if (chl->order == AV_CHANNEL_ORDER_UNSPEC)
return 0;
/* can compare masks directly */
if (chl->order != AV_CHANNEL_ORDER_CUSTOM &&
chl->order == chl1->order)
return chl->u.mask != chl1->u.mask;
/* compare channel by channel */
for (i = 0; i < chl->nb_channels; i++)
if (av_channel_layout_channel_from_index(chl, i) !=
av_channel_layout_channel_from_index(chl1, i))
return 1;
return 0;
}
void av_channel_layout_default(AVChannelLayout *ch_layout, int nb_channels)
{
int i;
for (i = 0; i < FF_ARRAY_ELEMS(channel_layout_map); i++)
if (nb_channels == channel_layout_map[i].layout.nb_channels) {
*ch_layout = channel_layout_map[i].layout;
return;
}
ch_layout->order = AV_CHANNEL_ORDER_UNSPEC;
ch_layout->nb_channels = nb_channels;
}
const AVChannelLayout *av_channel_layout_standard(void **opaque)
{
uintptr_t i = (uintptr_t)*opaque;
const AVChannelLayout *ch_layout = NULL;
if (i < FF_ARRAY_ELEMS(channel_layout_map)) {
ch_layout = &channel_layout_map[i].layout;
*opaque = (void*)(i + 1);
}
return ch_layout;
}
uint64_t av_channel_layout_subset(const AVChannelLayout *channel_layout,
uint64_t mask)
{
uint64_t ret = 0;
int i;
if (channel_layout->order == AV_CHANNEL_ORDER_NATIVE)
return channel_layout->u.mask & mask;
for (i = 0; i < 64; i++)
if (mask & (1ULL << i) && av_channel_layout_index_from_channel(channel_layout, i) >= 0)
ret |= (1ULL << i);
return ret;
}
Reference in New Issue View Git Blame Copy Permalink