[FFmpeg-devel] [PATCH 001/279] Add a new channel layout API
James Almer
jamrial at gmail.com
Wed Dec 8 03:06:17 EET 2021
From: Anton Khirnov <anton at khirnov.net>
The new API is more extensible and allows for custom layouts.
More accurate information is exported, eg for decoders that do not
set a channel layout, lavc will not make one up for them.
Deprecate the old API working with just uint64_t bitmasks.
Expanded and completed by Vittorio Giovara <vittorio.giovara at gmail.com>
and James Almer <jamrial at gmail.com>.
Signed-off-by: Vittorio Giovara <vittorio.giovara at gmail.com>
Signed-off-by: James Almer <jamrial at gmail.com>
---
libavutil/channel_layout.c | 498 ++++++++++++++++++++++++++++++------
libavutil/channel_layout.h | 510 ++++++++++++++++++++++++++++++++++---
libavutil/version.h | 1 +
3 files changed, 906 insertions(+), 103 deletions(-)
diff --git a/libavutil/channel_layout.c b/libavutil/channel_layout.c
index ac773a9e63..984255bfca 100644
--- a/libavutil/channel_layout.c
+++ b/libavutil/channel_layout.c
@@ -37,81 +37,132 @@ struct channel_name {
};
static const struct channel_name 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" },
- [31] = { "WL", "wide left" },
- [32] = { "WR", "wide right" },
- [33] = { "SDL", "surround direct left" },
- [34] = { "SDR", "surround direct right" },
- [35] = { "LFE2", "low frequency 2" },
- [36] = { "TSL", "top side left" },
- [37] = { "TSR", "top side right" },
- [38] = { "BFC", "bottom front center" },
- [39] = { "BFL", "bottom front left" },
- [40] = { "BFR", "bottom front right" },
+ [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(int channel_id)
+static const char *get_channel_name(enum AVChannel channel_id)
{
- if (channel_id < 0 || channel_id >= FF_ARRAY_ELEMS(channel_names))
- return NULL;
+ if ((unsigned) channel_id >= FF_ARRAY_ELEMS(channel_names) ||
+ !channel_names[channel_id].name)
+ return "?";
return channel_names[channel_id].name;
}
-static const struct {
+static inline void get_channel_str(AVBPrint *bp, const char *str,
+ enum AVChannel channel_id)
+{
+ if (str)
+ av_bprintf(bp, "%s", str);
+ else
+ av_bprintf(bp, "?");
+}
+
+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);
+ get_channel_str(&bp, (unsigned)channel_id < FF_ARRAY_ELEMS(channel_names) ?
+ channel_names[channel_id].name : NULL, channel_id);
+
+ return bp.len;
+}
+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);
+ get_channel_str(&bp, (unsigned)channel_id < FF_ARRAY_ELEMS(channel_names) ?
+ channel_names[channel_id].description : NULL, channel_id);
+
+ return bp.len;
+}
+
+enum AVChannel av_channel_from_string(const char *str)
+{
+ int i;
+ for (i = 0; i < FF_ARRAY_ELEMS(channel_names); i++) {
+ if (channel_names[i].name && !strcmp(str, channel_names[i].name))
+ return i;
+ }
+ return AV_CHAN_NONE;
+}
+
+struct channel_layout_name {
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 },
- { "3.0", 3, AV_CH_LAYOUT_SURROUND },
- { "3.0(back)", 3, AV_CH_LAYOUT_2_1 },
- { "4.0", 4, AV_CH_LAYOUT_4POINT0 },
- { "quad", 4, AV_CH_LAYOUT_QUAD },
- { "quad(side)", 4, AV_CH_LAYOUT_2_2 },
- { "3.1", 4, AV_CH_LAYOUT_3POINT1 },
- { "5.0", 5, AV_CH_LAYOUT_5POINT0_BACK },
- { "5.0(side)", 5, AV_CH_LAYOUT_5POINT0 },
- { "4.1", 5, AV_CH_LAYOUT_4POINT1 },
- { "5.1", 6, AV_CH_LAYOUT_5POINT1_BACK },
- { "5.1(side)", 6, AV_CH_LAYOUT_5POINT1 },
- { "6.0", 6, AV_CH_LAYOUT_6POINT0 },
- { "6.0(front)", 6, AV_CH_LAYOUT_6POINT0_FRONT },
- { "hexagonal", 6, AV_CH_LAYOUT_HEXAGONAL },
- { "6.1", 7, AV_CH_LAYOUT_6POINT1 },
- { "6.1(back)", 7, AV_CH_LAYOUT_6POINT1_BACK },
- { "6.1(front)", 7, AV_CH_LAYOUT_6POINT1_FRONT },
- { "7.0", 7, AV_CH_LAYOUT_7POINT0 },
- { "7.0(front)", 7, AV_CH_LAYOUT_7POINT0_FRONT },
- { "7.1", 8, AV_CH_LAYOUT_7POINT1 },
- { "7.1(wide)", 8, AV_CH_LAYOUT_7POINT1_WIDE_BACK },
- { "7.1(wide-side)", 8, AV_CH_LAYOUT_7POINT1_WIDE },
- { "octagonal", 8, AV_CH_LAYOUT_OCTAGONAL },
- { "hexadecagonal", 16, AV_CH_LAYOUT_HEXADECAGONAL },
- { "downmix", 2, AV_CH_LAYOUT_STEREO_DOWNMIX, },
- { "22.2", 24, AV_CH_LAYOUT_22POINT2, },
+ 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;
@@ -121,7 +172,7 @@ static uint64_t get_channel_layout_single(const char *name, int name_len)
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;
+ return channel_layout_map[i].layout.u.mask;
}
for (i = 0; i < FF_ARRAY_ELEMS(channel_names); i++)
if (channel_names[i].name &&
@@ -189,8 +240,8 @@ void av_bprint_channel_layout(struct AVBPrint *bp,
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].nb_channels &&
- channel_layout == channel_layout_map[i].layout) {
+ 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;
}
@@ -231,8 +282,8 @@ int av_get_channel_layout_nb_channels(uint64_t 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].nb_channels)
- return channel_layout_map[i].layout;
+ if (nb_channels == channel_layout_map[i].layout.nb_channels)
+ return channel_layout_map[i].layout.u.mask;
return 0;
}
@@ -287,7 +338,310 @@ int av_get_standard_channel_layout(unsigned index, uint64_t *layout,
{
if (index >= FF_ARRAY_ELEMS(channel_layout_map))
return AVERROR_EOF;
- if (layout) *layout = channel_layout_map[index].layout;
+ 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, channels;
+ const char *dup = str;
+ char *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;
+ }
+ }
+
+ /* channel names */
+ while (*dup) {
+ char *chname = av_get_token(&dup, "|");
+ if (!chname)
+ return AVERROR(ENOMEM);
+ if (*dup)
+ dup++; // skip separator
+ for (i = 0; i < FF_ARRAY_ELEMS(channel_names); i++) {
+ if (channel_names[i].name && !strcmp(chname, channel_names[i].name)) {
+ mask |= 1ULL << i;
+ }
+ }
+ av_free(chname);
+ }
+ if (mask) {
+ av_channel_layout_from_mask(channel_layout, mask);
+ return 0;
+ }
+
+ /* channel layout mask */
+ if (!strncmp(str, "0x", 2) && sscanf(str + 2, "%"SCNx64, &mask) == 1) {
+ av_channel_layout_from_mask(channel_layout, mask);
+ return 0;
+ }
+
+ errno = 0;
+ channels = strtol(str, &end, 10);
+
+ /* number of channels */
+ if (!errno && *end == 'c' && !*(end + 1) && channels >= 0) {
+ av_channel_layout_default(channel_layout, channels);
+ return 0;
+ }
+
+ /* number of unordered channels */
+ if (!errno && (!*end || av_strnstr(str, "channels", strlen(str))) && channels >= 0) {
+ channel_layout->order = AV_CHANNEL_ORDER_UNSPEC;
+ channel_layout->nb_channels = channels;
+ return 0;
+ }
+
+ return AVERROR_INVALIDDATA;
+}
+
+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(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(const AVChannelLayout *channel_layout,
+ char *buf, size_t buf_size)
+{
+ AVBPrint bp;
+ int i;
+
+ if (!buf && buf_size)
+ return AVERROR(EINVAL);
+
+ av_bprint_init_for_buffer(&bp, buf, buf_size);
+
+ 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 bp.len;
+ }
+ // fall-through
+ case AV_CHANNEL_ORDER_CUSTOM:
+ for (i = 0; i < channel_layout->nb_channels; i++) {
+ enum AVChannel ch = av_channel_layout_channel_from_index(channel_layout, i);
+ const char *ch_name = get_channel_name(ch);
+
+ if (i)
+ av_bprintf(&bp, "|");
+ av_bprintf(&bp, "%s", ch_name);
+ }
+ if (channel_layout->nb_channels)
+ return bp.len;
+ // fall-through
+ case AV_CHANNEL_ORDER_UNSPEC:
+ av_bprintf(&bp, "%d channels", channel_layout->nb_channels);
+ return bp.len;
+ default:
+ return AVERROR(EINVAL);
+ }
+}
+
+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 *name)
+{
+ enum AVChannel;
+ int channel, ret;
+
+ switch (channel_layout->order) {
+ case AV_CHANNEL_ORDER_CUSTOM:
+ case AV_CHANNEL_ORDER_NATIVE:
+ channel = av_channel_from_string(name);
+ if (channel < 0)
+ return channel;
+ ret = av_channel_layout_index_from_channel(channel_layout, channel);
+ if (ret < 0)
+ return ret;
+ return channel;
+ }
+
+ return AV_CHAN_NONE;
+}
+
+int av_channel_layout_index_from_channel(const AVChannelLayout *channel_layout,
+ enum AVChannel channel)
+{
+ int i;
+
+ 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 (!(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 *name)
+{
+ int ret;
+
+ if (channel_layout->order == AV_CHANNEL_ORDER_UNSPEC)
+ return AVERROR(EINVAL);
+
+ ret = av_channel_from_string(name);
+ if (ret < 0)
+ return ret;
+ return av_channel_layout_index_from_channel(channel_layout, ret);
+}
+
+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:
+ return !!channel_layout->u.map;
+ 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;
+}
diff --git a/libavutil/channel_layout.h b/libavutil/channel_layout.h
index d39ae1177a..018e87ff0b 100644
--- a/libavutil/channel_layout.h
+++ b/libavutil/channel_layout.h
@@ -23,6 +23,10 @@
#define AVUTIL_CHANNEL_LAYOUT_H
#include <stdint.h>
+#include <stdlib.h>
+
+#include "version.h"
+#include "attributes.h"
/**
* @file
@@ -34,6 +38,68 @@
* @{
*/
+enum AVChannel {
+ ///< Invalid channel index
+ AV_CHAN_NONE = -1,
+ AV_CHAN_FRONT_LEFT,
+ AV_CHAN_FRONT_RIGHT,
+ AV_CHAN_FRONT_CENTER,
+ AV_CHAN_LOW_FREQUENCY,
+ AV_CHAN_BACK_LEFT,
+ AV_CHAN_BACK_RIGHT,
+ AV_CHAN_FRONT_LEFT_OF_CENTER,
+ AV_CHAN_FRONT_RIGHT_OF_CENTER,
+ AV_CHAN_BACK_CENTER,
+ AV_CHAN_SIDE_LEFT,
+ AV_CHAN_SIDE_RIGHT,
+ AV_CHAN_TOP_CENTER,
+ AV_CHAN_TOP_FRONT_LEFT,
+ AV_CHAN_TOP_FRONT_CENTER,
+ AV_CHAN_TOP_FRONT_RIGHT,
+ AV_CHAN_TOP_BACK_LEFT,
+ AV_CHAN_TOP_BACK_CENTER,
+ AV_CHAN_TOP_BACK_RIGHT,
+ /** Stereo downmix. */
+ AV_CHAN_STEREO_LEFT = 29,
+ /** See above. */
+ AV_CHAN_STEREO_RIGHT,
+ AV_CHAN_WIDE_LEFT,
+ AV_CHAN_WIDE_RIGHT,
+ AV_CHAN_SURROUND_DIRECT_LEFT,
+ AV_CHAN_SURROUND_DIRECT_RIGHT,
+ AV_CHAN_LOW_FREQUENCY_2,
+ AV_CHAN_TOP_SIDE_LEFT,
+ AV_CHAN_TOP_SIDE_RIGHT,
+ AV_CHAN_BOTTOM_FRONT_CENTER,
+ AV_CHAN_BOTTOM_FRONT_LEFT,
+ AV_CHAN_BOTTOM_FRONT_RIGHT,
+
+ /** Channel is empty can be safely skipped. */
+ AV_CHAN_SILENCE = 64,
+};
+
+enum AVChannelOrder {
+ /**
+ * Only the channel count is specified, without any further information
+ * about the channel order.
+ */
+ AV_CHANNEL_ORDER_UNSPEC,
+ /**
+ * The native channel order, i.e. the channels are in the same order in
+ * which they are defined in the AVChannel enum. This supports up to 63
+ * different channels.
+ */
+ AV_CHANNEL_ORDER_NATIVE,
+ /**
+ * The channel order does not correspond to any other predefined order and
+ * is stored as an explicit map. For example, this could be used to support
+ * layouts with 64 or more channels, or with empty/skipped (AV_CHAN_SILENCE)
+ * channels at arbitrary positions.
+ */
+ AV_CHANNEL_ORDER_CUSTOM,
+};
+
+
/**
* @defgroup channel_masks Audio channel masks
*
@@ -46,41 +112,46 @@
*
* @{
*/
-#define AV_CH_FRONT_LEFT 0x00000001
-#define AV_CH_FRONT_RIGHT 0x00000002
-#define AV_CH_FRONT_CENTER 0x00000004
-#define AV_CH_LOW_FREQUENCY 0x00000008
-#define AV_CH_BACK_LEFT 0x00000010
-#define AV_CH_BACK_RIGHT 0x00000020
-#define AV_CH_FRONT_LEFT_OF_CENTER 0x00000040
-#define AV_CH_FRONT_RIGHT_OF_CENTER 0x00000080
-#define AV_CH_BACK_CENTER 0x00000100
-#define AV_CH_SIDE_LEFT 0x00000200
-#define AV_CH_SIDE_RIGHT 0x00000400
-#define AV_CH_TOP_CENTER 0x00000800
-#define AV_CH_TOP_FRONT_LEFT 0x00001000
-#define AV_CH_TOP_FRONT_CENTER 0x00002000
-#define AV_CH_TOP_FRONT_RIGHT 0x00004000
-#define AV_CH_TOP_BACK_LEFT 0x00008000
-#define AV_CH_TOP_BACK_CENTER 0x00010000
-#define AV_CH_TOP_BACK_RIGHT 0x00020000
-#define AV_CH_STEREO_LEFT 0x20000000 ///< Stereo downmix.
-#define AV_CH_STEREO_RIGHT 0x40000000 ///< See AV_CH_STEREO_LEFT.
-#define AV_CH_WIDE_LEFT 0x0000000080000000ULL
-#define AV_CH_WIDE_RIGHT 0x0000000100000000ULL
-#define AV_CH_SURROUND_DIRECT_LEFT 0x0000000200000000ULL
-#define AV_CH_SURROUND_DIRECT_RIGHT 0x0000000400000000ULL
-#define AV_CH_LOW_FREQUENCY_2 0x0000000800000000ULL
-#define AV_CH_TOP_SIDE_LEFT 0x0000001000000000ULL
-#define AV_CH_TOP_SIDE_RIGHT 0x0000002000000000ULL
-#define AV_CH_BOTTOM_FRONT_CENTER 0x0000004000000000ULL
-#define AV_CH_BOTTOM_FRONT_LEFT 0x0000008000000000ULL
-#define AV_CH_BOTTOM_FRONT_RIGHT 0x0000010000000000ULL
+#define AV_CH_FRONT_LEFT (1ULL << AV_CHAN_FRONT_LEFT )
+#define AV_CH_FRONT_RIGHT (1ULL << AV_CHAN_FRONT_RIGHT )
+#define AV_CH_FRONT_CENTER (1ULL << AV_CHAN_FRONT_CENTER )
+#define AV_CH_LOW_FREQUENCY (1ULL << AV_CHAN_LOW_FREQUENCY )
+#define AV_CH_BACK_LEFT (1ULL << AV_CHAN_BACK_LEFT )
+#define AV_CH_BACK_RIGHT (1ULL << AV_CHAN_BACK_RIGHT )
+#define AV_CH_FRONT_LEFT_OF_CENTER (1ULL << AV_CHAN_FRONT_LEFT_OF_CENTER )
+#define AV_CH_FRONT_RIGHT_OF_CENTER (1ULL << AV_CHAN_FRONT_RIGHT_OF_CENTER)
+#define AV_CH_BACK_CENTER (1ULL << AV_CHAN_BACK_CENTER )
+#define AV_CH_SIDE_LEFT (1ULL << AV_CHAN_SIDE_LEFT )
+#define AV_CH_SIDE_RIGHT (1ULL << AV_CHAN_SIDE_RIGHT )
+#define AV_CH_TOP_CENTER (1ULL << AV_CHAN_TOP_CENTER )
+#define AV_CH_TOP_FRONT_LEFT (1ULL << AV_CHAN_TOP_FRONT_LEFT )
+#define AV_CH_TOP_FRONT_CENTER (1ULL << AV_CHAN_TOP_FRONT_CENTER )
+#define AV_CH_TOP_FRONT_RIGHT (1ULL << AV_CHAN_TOP_FRONT_RIGHT )
+#define AV_CH_TOP_BACK_LEFT (1ULL << AV_CHAN_TOP_BACK_LEFT )
+#define AV_CH_TOP_BACK_CENTER (1ULL << AV_CHAN_TOP_BACK_CENTER )
+#define AV_CH_TOP_BACK_RIGHT (1ULL << AV_CHAN_TOP_BACK_RIGHT )
+#define AV_CH_STEREO_LEFT (1ULL << AV_CHAN_STEREO_LEFT )
+#define AV_CH_STEREO_RIGHT (1ULL << AV_CHAN_STEREO_RIGHT )
+#define AV_CH_WIDE_LEFT (1ULL << AV_CHAN_WIDE_LEFT )
+#define AV_CH_WIDE_RIGHT (1ULL << AV_CHAN_WIDE_RIGHT )
+#define AV_CH_SURROUND_DIRECT_LEFT (1ULL << AV_CHAN_SURROUND_DIRECT_LEFT )
+#define AV_CH_SURROUND_DIRECT_RIGHT (1ULL << AV_CHAN_SURROUND_DIRECT_RIGHT)
+#define AV_CH_LOW_FREQUENCY_2 (1ULL << AV_CHAN_LOW_FREQUENCY_2 )
+#define AV_CH_TOP_SIDE_LEFT (1ULL << AV_CHAN_TOP_SIDE_LEFT )
+#define AV_CH_TOP_SIDE_RIGHT (1ULL << AV_CHAN_TOP_SIDE_RIGHT )
+#define AV_CH_BOTTOM_FRONT_CENTER (1ULL << AV_CHAN_BOTTOM_FRONT_CENTER )
+#define AV_CH_BOTTOM_FRONT_LEFT (1ULL << AV_CHAN_BOTTOM_FRONT_LEFT )
+#define AV_CH_BOTTOM_FRONT_RIGHT (1ULL << AV_CHAN_BOTTOM_FRONT_RIGHT )
+#if FF_API_OLD_CHANNEL_LAYOUT
/** Channel mask value used for AVCodecContext.request_channel_layout
to indicate that the user requests the channel order of the decoder output
- to be the native codec channel order. */
+ to be the native codec channel order.
+ @deprecated channel order is now indicated in a special field in
+ AVChannelLayout
+ */
#define AV_CH_LAYOUT_NATIVE 0x8000000000000000ULL
+#endif
/**
* @}
@@ -128,6 +199,157 @@ enum AVMatrixEncoding {
AV_MATRIX_ENCODING_NB
};
+/**
+ * @}
+ */
+
+/**
+ * An AVChannelCustom defines a single channel within a custom order layout
+ *
+ * Unlike most structures in FFmpeg, sizeof(AVChannelCustom) is a part of the
+ * public ABI.
+ *
+ * No new fields may be added to it without a major version bump.
+ */
+typedef struct AVChannelCustom {
+ enum AVChannel id;
+} AVChannelCustom;
+
+/**
+ * An AVChannelLayout holds information about the channel layout of audio data.
+ *
+ * A channel layout here is defined as a set of channels ordered in a specific
+ * way (unless the channel order is AV_CHANNEL_ORDER_UNSPEC, in which case an
+ * AVChannelLayout carries only the channel count).
+ *
+ * Unlike most structures in Libav, sizeof(AVChannelLayout) is a part of the
+ * public ABI and may be used by the caller. E.g. it may be allocated on stack
+ * or embedded in caller-defined structs.
+ *
+ * AVChannelLayout can be initialized as follows:
+ * - default initialization with {0}, followed by by setting all used fields
+ * correctly;
+ * - by assigning one of the predefined AV_CHANNEL_LAYOUT_* initializers;
+ * - with a constructor function, such as av_channel_layout_default(),
+ * av_channel_layout_from_mask() or av_channel_layout_from_string().
+ *
+ * The channel layout must be unitialized with av_channel_layout_uninit()
+ * (strictly speaking this is not necessary for AV_CHANNEL_ORDER_NATIVE and
+ * AV_CHANNEL_ORDER_UNSPEC, but we recommend always calling
+ * av_channel_layout_uninit() regardless of the channel order used).
+ *
+ * Copying an AVChannelLayout via assigning is forbidden,
+ * av_channel_layout_copy() must be used. instead (and its return value should
+ * be checked)
+ *
+ * No new fields may be added to it without a major version bump, except for
+ * new elements of the union fitting in sizeof(uint64_t).
+ */
+typedef struct AVChannelLayout {
+ /**
+ * Channel order used in this layout.
+ * This is a mandatory field.
+ */
+ enum AVChannelOrder order;
+
+ /**
+ * Number of channels in this layout. Mandatory field.
+ */
+ int nb_channels;
+
+ /**
+ * Details about which channels are present in this layout.
+ * For AV_CHANNEL_ORDER_UNSPEC, this field is undefined and must not be
+ * used.
+ */
+ union {
+ /**
+ * This member must be used for AV_CHANNEL_ORDER_NATIVE.
+ * It is a bitmask, where the position of each set bit means that the
+ * AVChannel with the corresponding value is present.
+ *
+ * I.e. when (mask & (1 << AV_CHAN_FOO)) is non-zero, then AV_CHAN_FOO
+ * is present in the layout. Otherwise it is not present.
+ *
+ * @note when a channel layout using a bitmask is constructed or
+ * modified manually (i.e. not using any of the av_channel_layout_*
+ * functions), the code doing it must ensure that the number of set bits
+ * is equal to nb_channels.
+ */
+ uint64_t mask;
+ /**
+ * This member must be used when the channel order is
+ * AV_CHANNEL_ORDER_CUSTOM. It is a nb_channels-sized array, with each
+ * element signalling the presence of the AVChannel with the
+ * corresponding value in map[i].id.
+ *
+ * I.e. when map[i].id is equal to AV_CHAN_FOO, then AV_CH_FOO is the
+ * i-th channel in the audio data.
+ */
+ AVChannelCustom *map;
+ } u;
+} AVChannelLayout;
+
+#define AV_CHANNEL_LAYOUT_MONO \
+ { .order = AV_CHANNEL_ORDER_NATIVE, .nb_channels = 1, .u = { .mask = AV_CH_LAYOUT_MONO }}
+#define AV_CHANNEL_LAYOUT_STEREO \
+ { .order = AV_CHANNEL_ORDER_NATIVE, .nb_channels = 2, .u = { .mask = AV_CH_LAYOUT_STEREO }}
+#define AV_CHANNEL_LAYOUT_2POINT1 \
+ { .order = AV_CHANNEL_ORDER_NATIVE, .nb_channels = 3, .u = { .mask = AV_CH_LAYOUT_2POINT1 }}
+#define AV_CHANNEL_LAYOUT_2_1 \
+ { .order = AV_CHANNEL_ORDER_NATIVE, .nb_channels = 3, .u = { .mask = AV_CH_LAYOUT_2_1 }}
+#define AV_CHANNEL_LAYOUT_SURROUND \
+ { .order = AV_CHANNEL_ORDER_NATIVE, .nb_channels = 3, .u = { .mask = AV_CH_LAYOUT_SURROUND }}
+#define AV_CHANNEL_LAYOUT_3POINT1 \
+ { .order = AV_CHANNEL_ORDER_NATIVE, .nb_channels = 4, .u = { .mask = AV_CH_LAYOUT_3POINT1 }}
+#define AV_CHANNEL_LAYOUT_4POINT0 \
+ { .order = AV_CHANNEL_ORDER_NATIVE, .nb_channels = 4, .u = { .mask = AV_CH_LAYOUT_4POINT0 }}
+#define AV_CHANNEL_LAYOUT_4POINT1 \
+ { .order = AV_CHANNEL_ORDER_NATIVE, .nb_channels = 5, .u = { .mask = AV_CH_LAYOUT_4POINT1 }}
+#define AV_CHANNEL_LAYOUT_2_2 \
+ { .order = AV_CHANNEL_ORDER_NATIVE, .nb_channels = 4, .u = { .mask = AV_CH_LAYOUT_2_2 }}
+#define AV_CHANNEL_LAYOUT_QUAD \
+ { .order = AV_CHANNEL_ORDER_NATIVE, .nb_channels = 4, .u = { .mask = AV_CH_LAYOUT_QUAD }}
+#define AV_CHANNEL_LAYOUT_5POINT0 \
+ { .order = AV_CHANNEL_ORDER_NATIVE, .nb_channels = 5, .u = { .mask = AV_CH_LAYOUT_5POINT0 }}
+#define AV_CHANNEL_LAYOUT_5POINT1 \
+ { .order = AV_CHANNEL_ORDER_NATIVE, .nb_channels = 6, .u = { .mask = AV_CH_LAYOUT_5POINT1 }}
+#define AV_CHANNEL_LAYOUT_5POINT0_BACK \
+ { .order = AV_CHANNEL_ORDER_NATIVE, .nb_channels = 5, .u = { .mask = AV_CH_LAYOUT_5POINT0_BACK }}
+#define AV_CHANNEL_LAYOUT_5POINT1_BACK \
+ { .order = AV_CHANNEL_ORDER_NATIVE, .nb_channels = 6, .u = { .mask = AV_CH_LAYOUT_5POINT1_BACK }}
+#define AV_CHANNEL_LAYOUT_6POINT0 \
+ { .order = AV_CHANNEL_ORDER_NATIVE, .nb_channels = 6, .u = { .mask = AV_CH_LAYOUT_6POINT0 }}
+#define AV_CHANNEL_LAYOUT_6POINT0_FRONT \
+ { .order = AV_CHANNEL_ORDER_NATIVE, .nb_channels = 6, .u = { .mask = AV_CH_LAYOUT_6POINT0_FRONT }}
+#define AV_CHANNEL_LAYOUT_HEXAGONAL \
+ { .order = AV_CHANNEL_ORDER_NATIVE, .nb_channels = 6, .u = { .mask = AV_CH_LAYOUT_HEXAGONAL }}
+#define AV_CHANNEL_LAYOUT_6POINT1 \
+ { .order = AV_CHANNEL_ORDER_NATIVE, .nb_channels = 7, .u = { .mask = AV_CH_LAYOUT_6POINT1 }}
+#define AV_CHANNEL_LAYOUT_6POINT1_BACK \
+ { .order = AV_CHANNEL_ORDER_NATIVE, .nb_channels = 7, .u = { .mask = AV_CH_LAYOUT_6POINT1_BACK }}
+#define AV_CHANNEL_LAYOUT_6POINT1_FRONT \
+ { .order = AV_CHANNEL_ORDER_NATIVE, .nb_channels = 7, .u = { .mask = AV_CH_LAYOUT_6POINT1_FRONT }}
+#define AV_CHANNEL_LAYOUT_7POINT0 \
+ { .order = AV_CHANNEL_ORDER_NATIVE, .nb_channels = 7, .u = { .mask = AV_CH_LAYOUT_7POINT0 }}
+#define AV_CHANNEL_LAYOUT_7POINT0_FRONT \
+ { .order = AV_CHANNEL_ORDER_NATIVE, .nb_channels = 7, .u = { .mask = AV_CH_LAYOUT_7POINT0_FRONT }}
+#define AV_CHANNEL_LAYOUT_7POINT1 \
+ { .order = AV_CHANNEL_ORDER_NATIVE, .nb_channels = 8, .u = { .mask = AV_CH_LAYOUT_7POINT1 }}
+#define AV_CHANNEL_LAYOUT_7POINT1_WIDE \
+ { .order = AV_CHANNEL_ORDER_NATIVE, .nb_channels = 8, .u = { .mask = AV_CH_LAYOUT_7POINT1_WIDE }}
+#define AV_CHANNEL_LAYOUT_7POINT1_WIDE_BACK \
+ { .order = AV_CHANNEL_ORDER_NATIVE, .nb_channels = 8, .u = { .mask = AV_CH_LAYOUT_7POINT1_WIDE_BACK }}
+#define AV_CHANNEL_LAYOUT_OCTAGONAL \
+ { .order = AV_CHANNEL_ORDER_NATIVE, .nb_channels = 8, .u = { .mask = AV_CH_LAYOUT_OCTAGONAL }}
+#define AV_CHANNEL_LAYOUT_HEXADECAGONAL \
+ { .order = AV_CHANNEL_ORDER_NATIVE, .nb_channels = 16, .u = { .mask = AV_CH_LAYOUT_HEXAGONAL }}
+#define AV_CHANNEL_LAYOUT_STEREO_DOWNMIX \
+ { .order = AV_CHANNEL_ORDER_NATIVE, .nb_channels = 2, .u = { .mask = AV_CH_LAYOUT_STEREO_DOWNMIX }}
+#define AV_CHANNEL_LAYOUT_22POINT2 \
+ { .order = AV_CHANNEL_ORDER_NATIVE, .nb_channels = 24, .u = { .mask = AV_CH_LAYOUT_22POINT2 }}
+
+#if FF_API_OLD_CHANNEL_LAYOUT
/**
* Return a channel layout id that matches name, or 0 if no match is found.
*
@@ -144,7 +366,10 @@ enum AVMatrixEncoding {
* AV_CH_* macros).
*
* Example: "stereo+FC" = "2c+FC" = "2c+1c" = "0x7"
+ *
+ * @deprecated use av_channel_layout_from_string()
*/
+attribute_deprecated
uint64_t av_get_channel_layout(const char *name);
/**
@@ -158,7 +383,9 @@ uint64_t av_get_channel_layout(const char *name);
* @param[out] nb_channels number of channels
*
* @return 0 on success, AVERROR(EINVAL) if the parsing fails.
+ * @deprecated use av_channel_layout_from_string()
*/
+attribute_deprecated
int av_get_extended_channel_layout(const char *name, uint64_t* channel_layout, int* nb_channels);
/**
@@ -167,23 +394,32 @@ int av_get_extended_channel_layout(const char *name, uint64_t* channel_layout, i
*
* @param buf put here the string containing the channel layout
* @param buf_size size in bytes of the buffer
+ * @deprecated use av_channel_layout_describe()
*/
+attribute_deprecated
void av_get_channel_layout_string(char *buf, int buf_size, int nb_channels, uint64_t channel_layout);
struct AVBPrint;
/**
* Append a description of a channel layout to a bprint buffer.
+ * @deprecated use av_channel_layout_describe()
*/
+attribute_deprecated
void av_bprint_channel_layout(struct AVBPrint *bp, int nb_channels, uint64_t channel_layout);
/**
* Return the number of channels in the channel layout.
+ * @deprecated use AVChannelLayout.nb_channels
*/
+attribute_deprecated
int av_get_channel_layout_nb_channels(uint64_t channel_layout);
/**
* Return default channel layout for a given number of channels.
+ *
+ * @deprecated use av_channel_layout_default()
*/
+attribute_deprecated
int64_t av_get_default_channel_layout(int nb_channels);
/**
@@ -194,20 +430,28 @@ int64_t av_get_default_channel_layout(int nb_channels);
*
* @return index of channel in channel_layout on success, a negative AVERROR
* on error.
+ *
+ * @deprecated use av_channel_layout_index_from_channel()
*/
+attribute_deprecated
int av_get_channel_layout_channel_index(uint64_t channel_layout,
uint64_t channel);
/**
* Get the channel with the given index in channel_layout.
+ * @deprecated use av_channel_layout_channel_from_index()
*/
+attribute_deprecated
uint64_t av_channel_layout_extract_channel(uint64_t channel_layout, int index);
/**
* Get the name of a given channel.
*
* @return channel name on success, NULL on error.
+ *
+ * @deprecated use av_channel_name()
*/
+attribute_deprecated
const char *av_get_channel_name(uint64_t channel);
/**
@@ -215,7 +459,9 @@ const char *av_get_channel_name(uint64_t channel);
*
* @param channel a channel layout with a single channel
* @return channel description on success, NULL on error
+ * @deprecated use av_channel_description()
*/
+attribute_deprecated
const char *av_get_channel_description(uint64_t channel);
/**
@@ -226,9 +472,211 @@ const char *av_get_channel_description(uint64_t channel);
* @param[out] name name of the layout
* @return 0 if the layout exists,
* <0 if index is beyond the limits
+ * @deprecated use av_channel_layout_standard()
*/
+attribute_deprecated
int av_get_standard_channel_layout(unsigned index, uint64_t *layout,
const char **name);
+#endif
+
+/**
+ * Get a human readable string in an abbreviated form describing a given channel,
+ * or "?" if not found.
+ * This is the inverse function of @ref av_channel_from_string().
+ *
+ * @param buf pre-allocated buffer where to put the generated string
+ * @param buf_size size in bytes of the buffer.
+ * @return amount of bytes needed to hold the output string, or a negative AVERROR
+ * on failure. If the returned value is bigger than buf_size, then the
+ * string was truncated.
+ */
+int av_channel_name(char *buf, size_t buf_size, enum AVChannel channel);
+
+/**
+ * Get a human readable string describing a given channel, or "?" if not found.
+ *
+ * @param buf pre-allocated buffer where to put the generated string
+ * @param buf_size size in bytes of the buffer.
+ * @return amount of bytes needed to hold the output string, or a negative AVERROR
+ * on failure. If the returned value is bigger than buf_size, then the
+ * string was truncated.
+ */
+int av_channel_description(char *buf, size_t buf_size, enum AVChannel channel);
+
+/**
+ * This is the inverse function of @ref av_channel_name().
+ *
+ * @return the channel with the given name
+ * AV_CHAN_NONE when name does not identify a known channel
+ */
+enum AVChannel av_channel_from_string(const char *name);
+
+/**
+ * Initialize a native channel layout from a bitmask indicating which channels
+ * are present.
+ *
+ * @param channel_layout the layout structure to be initialized
+ * @param mask bitmask describing the channel layout
+ *
+ * @return 0 on success
+ * AVERROR(EINVAL) for invalid mask values
+ */
+int av_channel_layout_from_mask(AVChannelLayout *channel_layout, uint64_t mask);
+
+/**
+ * Initialize a channel layout from a given string description.
+ * The input string can be represented by:
+ * - the formal channel layout name (returned by av_channel_layout_describe())
+ * - single or multiple channel names (returned by av_channel_name()
+ * or concatenated with "|")
+ * - a hexadecimal value of a channel layout (eg. "0x4")
+ * - the number of channels with default layout (eg. "5c")
+ * - the number of unordered channels (eg. "4" or "4 channels")
+ *
+ * @param channel_layout input channel layout
+ * @param str string describing the channel layout
+ * @return 0 channel layout was detected, AVERROR_INVALIDATATA otherwise
+ */
+int av_channel_layout_from_string(AVChannelLayout *channel_layout,
+ const char *str);
+
+/**
+ * Get the default channel layout for a given number of channels.
+ *
+ * @param channel_layout the layout structure to be initialized
+ * @param nb_channels number of channels
+ */
+void av_channel_layout_default(AVChannelLayout *ch_layout, int nb_channels);
+
+/**
+ * Iterate over all standard channel layouts.
+ *
+ * @param opaque a pointer where libavutil will store the iteration state. Must
+ * point to NULL to start the iteration.
+ *
+ * @return the standard channel layout or NULL when the iteration is
+ * finished
+ */
+const AVChannelLayout *av_channel_layout_standard(void **opaque);
+
+/**
+ * Free any allocated data in the channel layout and reset the channel
+ * count to 0.
+ *
+ * @param channel_layout the layout structure to be uninitialized
+ */
+void av_channel_layout_uninit(AVChannelLayout *channel_layout);
+
+/**
+ * Make a copy of a channel layout. This differs from just assigning src to dst
+ * in that it allocates and copies the map for AV_CHANNEL_ORDER_CUSTOM.
+ *
+ * @note the destination channel_layout will be always uninitialized before copy.
+ *
+ * @param dst destination channel layout
+ * @param src source channel layout
+ * @return 0 on success, a negative AVERROR on error.
+ */
+int av_channel_layout_copy(AVChannelLayout *dst, const AVChannelLayout *src);
+
+/**
+ * Get a human-readable string describing the channel layout properties.
+ * The string will be in the same format that is accepted by
+ * @ref av_channel_layout_from_string().
+ *
+ * @param channel_layout channel layout to be described
+ * @param buf pre-allocated buffer where to put the generated string
+ * @param buf_size size in bytes of the buffer.
+ * @return amount of bytes needed to hold the output string, or a negative AVERROR
+ * on failure. If the returned value is bigger than buf_size, then the
+ * string was truncated.
+ */
+int av_channel_layout_describe(const AVChannelLayout *channel_layout,
+ char *buf, size_t buf_size);
+
+/**
+ * Get the channel with the given index in a channel layout.
+ *
+ * @param channel_layout input channel layout
+ * @return channel with the index idx in channel_layout on success or
+ * AV_CHAN_NONE on failure (if idx is not valid or the channel order is
+ * unspecified)
+ */
+enum AVChannel
+av_channel_layout_channel_from_index(const AVChannelLayout *channel_layout, unsigned int idx);
+
+/**
+ * Get the index of a given channel in a channel layout. In case multiple
+ * channels are found, only the first match will be returned.
+ *
+ * @param channel_layout input channel layout
+ * @return index of channel in channel_layout on success or a negative number if
+ * channel is not present in channel_layout.
+ */
+int av_channel_layout_index_from_channel(const AVChannelLayout *channel_layout,
+ enum AVChannel channel);
+
+/**
+ * Get the index in a channel layout of a channel described by the given string.
+ * In case multiple channels are found, only the first match will be returned.
+ *
+ * This function accepts channel names in the same format as
+ * @ref av_channel_from_string().
+ *
+ * @param channel_layout input channel layout
+ * @return a channel index described by the given string, or a negative AVERROR
+ * value.
+ */
+int av_channel_layout_index_from_string(const AVChannelLayout *channel_layout,
+ const char *name);
+
+/**
+ * Get a channel described by the given string.
+ *
+ * This function accepts channel names in the same format as
+ * @ref av_channel_from_string().
+ *
+ * @param channel_layout input channel layout
+ * @return a channel described by the given string, or a negative AVERROR value.
+ */
+int av_channel_layout_channel_from_string(const AVChannelLayout *channel_layout,
+ const char *name);
+
+/**
+ * Find out what channels from a given set are present in a channel layout,
+ * without regard for their positions.
+ *
+ * @param channel_layout input channel layout
+ * @param mask a combination of AV_CH_* representing a set of channels
+ * @return a bitfield representing all the channels from mask that are present
+ * in channel_layout
+ */
+uint64_t av_channel_layout_subset(const AVChannelLayout *channel_layout,
+ uint64_t mask);
+
+/**
+ * Check whether a channel layout is valid, i.e. can possibly describe audio
+ * data.
+ *
+ * @param channel_layout input channel layout
+ * @return 1 if channel_layout is valid, 0 otherwise.
+ */
+int av_channel_layout_check(const AVChannelLayout *channel_layout);
+
+/**
+ * Check whether two channel layouts are semantically the same, i.e. the same
+ * channels are present on the same positions in both.
+ *
+ * If one of the channel layouts is AV_CHANNEL_ORDER_UNSPEC, while the other is
+ * not, they are considered to be unequal. If both are AV_CHANNEL_ORDER_UNSPEC,
+ * they are considered equal iff the channel counts are the same in both.
+ *
+ * @param chl input channel layout
+ * @param chl1 input channel layout
+ * @return 0 if chl and chl1 are equal, 1 if they are not equal. A negative
+ * AVERROR code if one or both are invalid.
+ */
+int av_channel_layout_compare(const AVChannelLayout *chl, const AVChannelLayout *chl1);
/**
* @}
diff --git a/libavutil/version.h b/libavutil/version.h
index 017fc277a6..d7179e1fdd 100644
--- a/libavutil/version.h
+++ b/libavutil/version.h
@@ -109,6 +109,7 @@
#define FF_API_DECLARE_ALIGNED (LIBAVUTIL_VERSION_MAJOR < 58)
#define FF_API_COLORSPACE_NAME (LIBAVUTIL_VERSION_MAJOR < 58)
#define FF_API_AV_MALLOCZ_ARRAY (LIBAVUTIL_VERSION_MAJOR < 58)
+#define FF_API_OLD_CHANNEL_LAYOUT (LIBAVUTIL_VERSION_MAJOR < 58)
/**
* @}
--
2.34.1
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