gstreamer/gst-libs/gst/audio/audio-channels.c

696 lines
21 KiB
C

/* GStreamer
* Copyright (C) <1999> Erik Walthinsen <omega@cse.ogi.edu>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
/**
* SECTION:gstaudiochannels
* @title: Audio-channels
* @short_description: Support library for audio channel handling
*
* This library contains some helper functions for multichannel audio.
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include <string.h>
#include "audio-channels.h"
#ifndef GST_DISABLE_GST_DEBUG
#define GST_CAT_DEFAULT ensure_debug_category()
static GstDebugCategory *
ensure_debug_category (void)
{
static gsize cat_gonce = 0;
if (g_once_init_enter (&cat_gonce)) {
gsize cat_done;
cat_done = (gsize) _gst_debug_category_new ("audio-channels", 0,
"audio-channels object");
g_once_init_leave (&cat_gonce, cat_done);
}
return (GstDebugCategory *) cat_gonce;
}
#else
#define ensure_debug_category() /* NOOP */
#endif /* GST_DISABLE_GST_DEBUG */
static const GstAudioChannelPosition default_channel_order[64] = {
GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT,
GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT,
GST_AUDIO_CHANNEL_POSITION_FRONT_CENTER,
GST_AUDIO_CHANNEL_POSITION_LFE1,
GST_AUDIO_CHANNEL_POSITION_REAR_LEFT,
GST_AUDIO_CHANNEL_POSITION_REAR_RIGHT,
GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT_OF_CENTER,
GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT_OF_CENTER,
GST_AUDIO_CHANNEL_POSITION_REAR_CENTER,
GST_AUDIO_CHANNEL_POSITION_LFE2,
GST_AUDIO_CHANNEL_POSITION_SIDE_LEFT,
GST_AUDIO_CHANNEL_POSITION_SIDE_RIGHT,
GST_AUDIO_CHANNEL_POSITION_TOP_FRONT_LEFT,
GST_AUDIO_CHANNEL_POSITION_TOP_FRONT_RIGHT,
GST_AUDIO_CHANNEL_POSITION_TOP_FRONT_CENTER,
GST_AUDIO_CHANNEL_POSITION_TOP_CENTER,
GST_AUDIO_CHANNEL_POSITION_TOP_REAR_LEFT,
GST_AUDIO_CHANNEL_POSITION_TOP_REAR_RIGHT,
GST_AUDIO_CHANNEL_POSITION_TOP_SIDE_LEFT,
GST_AUDIO_CHANNEL_POSITION_TOP_SIDE_RIGHT,
GST_AUDIO_CHANNEL_POSITION_TOP_REAR_CENTER,
GST_AUDIO_CHANNEL_POSITION_BOTTOM_FRONT_CENTER,
GST_AUDIO_CHANNEL_POSITION_BOTTOM_FRONT_LEFT,
GST_AUDIO_CHANNEL_POSITION_BOTTOM_FRONT_RIGHT,
GST_AUDIO_CHANNEL_POSITION_WIDE_LEFT,
GST_AUDIO_CHANNEL_POSITION_WIDE_RIGHT,
GST_AUDIO_CHANNEL_POSITION_SURROUND_LEFT,
GST_AUDIO_CHANNEL_POSITION_SURROUND_RIGHT,
GST_AUDIO_CHANNEL_POSITION_INVALID,
GST_AUDIO_CHANNEL_POSITION_INVALID,
GST_AUDIO_CHANNEL_POSITION_INVALID,
GST_AUDIO_CHANNEL_POSITION_INVALID,
GST_AUDIO_CHANNEL_POSITION_INVALID,
GST_AUDIO_CHANNEL_POSITION_INVALID,
GST_AUDIO_CHANNEL_POSITION_INVALID,
GST_AUDIO_CHANNEL_POSITION_INVALID,
GST_AUDIO_CHANNEL_POSITION_INVALID,
GST_AUDIO_CHANNEL_POSITION_INVALID,
GST_AUDIO_CHANNEL_POSITION_INVALID,
GST_AUDIO_CHANNEL_POSITION_INVALID,
GST_AUDIO_CHANNEL_POSITION_INVALID,
GST_AUDIO_CHANNEL_POSITION_INVALID,
GST_AUDIO_CHANNEL_POSITION_INVALID,
GST_AUDIO_CHANNEL_POSITION_INVALID,
GST_AUDIO_CHANNEL_POSITION_INVALID,
GST_AUDIO_CHANNEL_POSITION_INVALID,
GST_AUDIO_CHANNEL_POSITION_INVALID,
GST_AUDIO_CHANNEL_POSITION_INVALID,
GST_AUDIO_CHANNEL_POSITION_INVALID,
GST_AUDIO_CHANNEL_POSITION_INVALID,
GST_AUDIO_CHANNEL_POSITION_INVALID,
GST_AUDIO_CHANNEL_POSITION_INVALID,
GST_AUDIO_CHANNEL_POSITION_INVALID,
GST_AUDIO_CHANNEL_POSITION_INVALID,
GST_AUDIO_CHANNEL_POSITION_INVALID,
GST_AUDIO_CHANNEL_POSITION_INVALID,
GST_AUDIO_CHANNEL_POSITION_INVALID,
GST_AUDIO_CHANNEL_POSITION_INVALID,
GST_AUDIO_CHANNEL_POSITION_INVALID,
GST_AUDIO_CHANNEL_POSITION_INVALID,
GST_AUDIO_CHANNEL_POSITION_INVALID,
GST_AUDIO_CHANNEL_POSITION_INVALID,
GST_AUDIO_CHANNEL_POSITION_INVALID,
GST_AUDIO_CHANNEL_POSITION_INVALID
};
/*
* Compares @channels audio channel positions @p1 and @p2 if they are equal.
* In other words, tells whether channel reordering is needed (unequal) or not (equal).
*
* Returns: %TRUE if the channel positions are equal, i.e. no reordering is needed.
*/
static gboolean
gst_audio_channel_positions_equal (const GstAudioChannelPosition * p1,
const GstAudioChannelPosition * p2, gint channels)
{
return memcmp (p1, p2, channels * sizeof (p1[0])) == 0;
}
static gboolean
check_valid_channel_positions (const GstAudioChannelPosition * position,
gint channels, gboolean enforce_order, guint64 * channel_mask_out)
{
gint i, j;
guint64 channel_mask = 0;
if (channels == 1 && position[0] == GST_AUDIO_CHANNEL_POSITION_MONO) {
if (channel_mask_out)
*channel_mask_out = 0;
return TRUE;
}
if (channels > 0 && position[0] == GST_AUDIO_CHANNEL_POSITION_NONE) {
if (channel_mask_out)
*channel_mask_out = 0;
return TRUE;
}
j = 0;
for (i = 0; i < channels; i++) {
while (j < G_N_ELEMENTS (default_channel_order)
&& default_channel_order[j] != position[i])
j++;
if (position[i] == GST_AUDIO_CHANNEL_POSITION_INVALID ||
position[i] == GST_AUDIO_CHANNEL_POSITION_MONO ||
position[i] == GST_AUDIO_CHANNEL_POSITION_NONE)
return FALSE;
/* Is this in valid channel order? */
if (enforce_order && j == G_N_ELEMENTS (default_channel_order))
return FALSE;
j++;
if ((channel_mask & (G_GUINT64_CONSTANT (1) << position[i])))
return FALSE;
channel_mask |= (G_GUINT64_CONSTANT (1) << position[i]);
}
if (channel_mask_out)
*channel_mask_out = channel_mask;
return TRUE;
}
/**
* gst_audio_reorder_channels:
* @data: (array length=size) (element-type guint8): The pointer to
* the memory.
* @size: The size of the memory.
* @format: The %GstAudioFormat of the buffer.
* @channels: The number of channels.
* @from: (array length=channels): The channel positions in the buffer.
* @to: (array length=channels): The channel positions to convert to.
*
* Reorders @data from the channel positions @from to the channel
* positions @to. @from and @to must contain the same number of
* positions and the same positions, only in a different order.
*
* Note: this function assumes the audio data is in interleaved layout
*
* Returns: %TRUE if the reordering was possible.
*/
gboolean
gst_audio_reorder_channels (gpointer data, gsize size, GstAudioFormat format,
gint channels, const GstAudioChannelPosition * from,
const GstAudioChannelPosition * to)
{
const GstAudioFormatInfo *info;
gint i, j, n;
gint reorder_map[64] = { 0, };
guint8 *ptr;
gint bpf, bps;
guint8 tmp[64 * 8];
info = gst_audio_format_get_info (format);
g_return_val_if_fail (data != NULL, FALSE);
g_return_val_if_fail (from != NULL, FALSE);
g_return_val_if_fail (to != NULL, FALSE);
g_return_val_if_fail (info != NULL && info->width > 0, FALSE);
g_return_val_if_fail (info->width > 0, FALSE);
g_return_val_if_fail (info->width <= 8 * 64, FALSE);
g_return_val_if_fail (size % ((info->width * channels) / 8) == 0, FALSE);
g_return_val_if_fail (channels > 0, FALSE);
g_return_val_if_fail (channels <= 64, FALSE);
if (size == 0)
return TRUE;
if (gst_audio_channel_positions_equal (from, to, channels))
return TRUE;
if (!gst_audio_get_channel_reorder_map (channels, from, to, reorder_map))
return FALSE;
bps = info->width / 8;
bpf = bps * channels;
ptr = data;
n = size / bpf;
for (i = 0; i < n; i++) {
memcpy (tmp, ptr, bpf);
for (j = 0; j < channels; j++)
memcpy (ptr + reorder_map[j] * bps, tmp + j * bps, bps);
ptr += bpf;
}
return TRUE;
}
static gboolean
gst_audio_meta_reorder_channels (GstAudioMeta * meta,
const GstAudioChannelPosition * from, const GstAudioChannelPosition * to)
{
gint reorder_map[64] = { 0, };
gsize tmp_offsets[64] = { 0, };
gint i;
g_return_val_if_fail (meta, FALSE);
g_return_val_if_fail (meta->info.channels > 0, FALSE);
g_return_val_if_fail (meta->info.channels <= 64, FALSE);
g_return_val_if_fail (meta->offsets != NULL, FALSE);
if (!gst_audio_get_channel_reorder_map (meta->info.channels, from, to,
reorder_map))
return FALSE;
memcpy (tmp_offsets, meta->offsets, meta->info.channels * sizeof (gsize));
for (i = 0; i < meta->info.channels; i++) {
meta->offsets[reorder_map[i]] = tmp_offsets[i];
}
return TRUE;
}
/**
* gst_audio_buffer_reorder_channels:
* @buffer: The buffer to reorder.
* @format: The %GstAudioFormat of the buffer.
* @channels: The number of channels.
* @from: (array length=channels): The channel positions in the buffer.
* @to: (array length=channels): The channel positions to convert to.
*
* Reorders @buffer from the channel positions @from to the channel
* positions @to. @from and @to must contain the same number of
* positions and the same positions, only in a different order.
* @buffer must be writable.
*
* Returns: %TRUE if the reordering was possible.
*/
gboolean
gst_audio_buffer_reorder_channels (GstBuffer * buffer,
GstAudioFormat format, gint channels,
const GstAudioChannelPosition * from, const GstAudioChannelPosition * to)
{
GstMapInfo info;
GstAudioMeta *meta;
gboolean ret = TRUE;
g_return_val_if_fail (GST_IS_BUFFER (buffer), FALSE);
g_return_val_if_fail (gst_buffer_is_writable (buffer), FALSE);
if (gst_audio_channel_positions_equal (from, to, channels))
return TRUE;
meta = gst_buffer_get_audio_meta (buffer);
if (meta && meta->info.layout == GST_AUDIO_LAYOUT_NON_INTERLEAVED) {
g_return_val_if_fail (channels == meta->info.channels, FALSE);
ret = gst_audio_meta_reorder_channels (meta, from, to);
} else {
if (!gst_buffer_map (buffer, &info, GST_MAP_READWRITE))
return FALSE;
ret = gst_audio_reorder_channels (info.data, info.size, format, channels,
from, to);
gst_buffer_unmap (buffer, &info);
}
return ret;
}
/**
* gst_audio_check_valid_channel_positions:
* @position: (array length=channels): The %GstAudioChannelPositions
* to check.
* @channels: The number of channels.
* @force_order: Only consider the GStreamer channel order.
*
* Checks if @position contains valid channel positions for
* @channels channels. If @force_order is %TRUE it additionally
* checks if the channels are in the order required by GStreamer.
*
* Returns: %TRUE if the channel positions are valid.
*/
gboolean
gst_audio_check_valid_channel_positions (const GstAudioChannelPosition *
position, gint channels, gboolean force_order)
{
return check_valid_channel_positions (position, channels, force_order, NULL);
}
/**
* gst_audio_channel_positions_to_mask:
* @position: (array length=channels): The %GstAudioChannelPositions
* @channels: The number of channels.
* @force_order: Only consider the GStreamer channel order.
* @channel_mask: (out): the output channel mask
*
* Convert the @position array of @channels channels to a bitmask.
*
* If @force_order is %TRUE it additionally checks if the channels are
* in the order required by GStreamer.
*
* Returns: %TRUE if the channel positions are valid and could be converted.
*/
gboolean
gst_audio_channel_positions_to_mask (const GstAudioChannelPosition * position,
gint channels, gboolean force_order, guint64 * channel_mask)
{
return check_valid_channel_positions (position, channels, force_order,
channel_mask);
}
/**
* gst_audio_channel_positions_from_mask:
* @channels: The number of channels
* @channel_mask: The input channel_mask
* @position: (array length=channels): The
* %GstAudioChannelPosition<!-- -->s
*
* Convert the @channels present in @channel_mask to a @position array
* (which should have at least @channels entries ensured by caller).
* If @channel_mask is set to 0, it is considered as 'not present' for purpose
* of conversion.
* A partially valid @channel_mask with less bits set than the number
* of channels is considered valid.
*
* Returns: %TRUE if channel and channel mask are valid and could be converted
*/
gboolean
gst_audio_channel_positions_from_mask (gint channels, guint64 channel_mask,
GstAudioChannelPosition * position)
{
g_return_val_if_fail (position != NULL, FALSE);
g_return_val_if_fail (channels != 0, FALSE);
GST_DEBUG ("converting %d channels for "
" channel mask 0x%016" G_GINT64_MODIFIER "x", channels, channel_mask);
if (!channel_mask) {
if (channels == 1) {
position[0] = GST_AUDIO_CHANNEL_POSITION_MONO;
} else if (channels == 2) {
position[0] = GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT;
position[1] = GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT;
} else {
goto no_channel_mask;
}
} else {
gint i, j;
j = 0;
for (i = 0; i < 64; i++) {
if ((channel_mask & (G_GUINT64_CONSTANT (1) << i))) {
if (j < channels)
position[j] = default_channel_order[i];
j++;
}
}
if (j != channels)
GST_WARNING ("Only partially valid channel mask 0x%016" G_GINT64_MODIFIER
"x for %d channels", channel_mask, channels);
}
return TRUE;
/* ERROR */
no_channel_mask:
{
GST_ERROR ("no channel-mask property given");
return FALSE;
}
}
/**
* gst_audio_get_channel_reorder_map:
* @channels: The number of channels.
* @from: (array length=channels): The channel positions to reorder from.
* @to: (array length=channels): The channel positions to reorder to.
* @reorder_map: (array length=channels): Pointer to the reorder map.
*
* Returns a reorder map for @from to @to that can be used in
* custom channel reordering code, e.g. to convert from or to the
* GStreamer channel order. @from and @to must contain the same
* number of positions and the same positions, only in a
* different order.
*
* The resulting @reorder_map can be used for reordering by assigning
* channel i of the input to channel reorder_map[i] of the output.
*
* Returns: %TRUE if the channel positions are valid and reordering
* is possible.
*/
gboolean
gst_audio_get_channel_reorder_map (gint channels,
const GstAudioChannelPosition * from, const GstAudioChannelPosition * to,
gint * reorder_map)
{
gint i, j;
g_return_val_if_fail (reorder_map != NULL, FALSE);
g_return_val_if_fail (channels > 0, FALSE);
g_return_val_if_fail (from != NULL, FALSE);
g_return_val_if_fail (to != NULL, FALSE);
g_return_val_if_fail (check_valid_channel_positions (from, channels, FALSE,
NULL), FALSE);
g_return_val_if_fail (check_valid_channel_positions (to, channels, FALSE,
NULL), FALSE);
/* Build reorder map and check compatibility */
for (i = 0; i < channels; i++) {
if (from[i] == GST_AUDIO_CHANNEL_POSITION_NONE
|| to[i] == GST_AUDIO_CHANNEL_POSITION_NONE)
return FALSE;
if (from[i] == GST_AUDIO_CHANNEL_POSITION_INVALID
|| to[i] == GST_AUDIO_CHANNEL_POSITION_INVALID)
return FALSE;
if (from[i] == GST_AUDIO_CHANNEL_POSITION_MONO
|| to[i] == GST_AUDIO_CHANNEL_POSITION_MONO)
return FALSE;
for (j = 0; j < channels; j++) {
if (from[i] == to[j]) {
reorder_map[i] = j;
break;
}
}
/* Not all channels present in both */
if (j == channels)
return FALSE;
}
return TRUE;
}
/**
* gst_audio_channel_positions_to_valid_order:
* @position: (array length=channels): The channel positions to
* reorder to.
* @channels: The number of channels.
*
* Reorders the channel positions in @position from any order to
* the GStreamer channel order.
*
* Returns: %TRUE if the channel positions are valid and reordering
* was successful.
*/
gboolean
gst_audio_channel_positions_to_valid_order (GstAudioChannelPosition * position,
gint channels)
{
GstAudioChannelPosition tmp[64];
guint64 channel_mask = 0;
gint i, j;
g_return_val_if_fail (channels > 0, FALSE);
g_return_val_if_fail (position != NULL, FALSE);
g_return_val_if_fail (check_valid_channel_positions (position, channels,
FALSE, NULL), FALSE);
if (channels == 1 && position[0] == GST_AUDIO_CHANNEL_POSITION_MONO)
return TRUE;
if (position[0] == GST_AUDIO_CHANNEL_POSITION_NONE)
return TRUE;
check_valid_channel_positions (position, channels, FALSE, &channel_mask);
memset (tmp, 0xff, sizeof (tmp));
j = 0;
for (i = 0; i < 64; i++) {
if ((channel_mask & (G_GUINT64_CONSTANT (1) << i))) {
tmp[j] = i;
j++;
}
}
memcpy (position, tmp, sizeof (tmp[0]) * channels);
return TRUE;
}
#define _P(pos) (G_GUINT64_CONSTANT (1) << GST_AUDIO_CHANNEL_POSITION_ ##pos)
static const guint64 default_masks[] = {
/* 1 channel */
0,
/* 2 channels */
_P (FRONT_LEFT) | _P (FRONT_RIGHT),
/* 3 channels (2.1) */
_P (FRONT_LEFT) | _P (FRONT_RIGHT) | _P (LFE1),
/* 4 channels (4.0) */
_P (FRONT_LEFT) | _P (FRONT_RIGHT) | _P (REAR_LEFT) | _P (REAR_RIGHT),
/* 5 channels */
_P (FRONT_LEFT) | _P (FRONT_RIGHT) | _P (REAR_LEFT) | _P (REAR_RIGHT)
| _P (FRONT_CENTER),
/* 6 channels (5.1) */
_P (FRONT_LEFT) |
_P (FRONT_RIGHT) |
_P (REAR_LEFT) | _P (REAR_RIGHT) | _P (FRONT_CENTER) | _P (LFE1),
/* 7 channels (6.1) */
_P (FRONT_LEFT) |
_P (FRONT_RIGHT) |
_P (REAR_LEFT) |
_P (REAR_RIGHT) | _P (FRONT_CENTER) | _P (LFE1) | _P (REAR_CENTER),
/* 8 channels (7.1) */
_P (FRONT_LEFT) |
_P (FRONT_RIGHT) |
_P (REAR_LEFT) |
_P (REAR_RIGHT) |
_P (FRONT_CENTER) | _P (LFE1) | _P (SIDE_LEFT) | _P (SIDE_RIGHT),
};
/**
* gst_audio_channel_get_fallback_mask:
* @channels: the number of channels
*
* Get the fallback channel-mask for the given number of channels.
*
* This function returns a reasonable fallback channel-mask and should be
* called as a last resort when the specific channel map is unknown.
*
* Returns: a fallback channel-mask for @channels or 0 when there is no
* mask and mono.
*
* Since: 1.8
*/
guint64
gst_audio_channel_get_fallback_mask (gint channels)
{
g_return_val_if_fail (channels > 0, 0);
if (channels > 8)
return 0;
return default_masks[channels - 1];
}
static const gchar *
position_to_string (GstAudioChannelPosition pos)
{
switch (pos) {
case GST_AUDIO_CHANNEL_POSITION_NONE:
return "NONE";
case GST_AUDIO_CHANNEL_POSITION_MONO:
return "MONO";
case GST_AUDIO_CHANNEL_POSITION_INVALID:
return "INVALID";
case GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT:
return "FL";
case GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT:
return "FR";
case GST_AUDIO_CHANNEL_POSITION_FRONT_CENTER:
return "FC";
case GST_AUDIO_CHANNEL_POSITION_LFE1:
return "LFE1";
case GST_AUDIO_CHANNEL_POSITION_REAR_LEFT:
return "RL";
case GST_AUDIO_CHANNEL_POSITION_REAR_RIGHT:
return "RR";
case GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT_OF_CENTER:
return "FLoC";
case GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT_OF_CENTER:
return "FRoC";
case GST_AUDIO_CHANNEL_POSITION_REAR_CENTER:
return "RC";
case GST_AUDIO_CHANNEL_POSITION_LFE2:
return "LF2";
case GST_AUDIO_CHANNEL_POSITION_SIDE_LEFT:
return "SL";
case GST_AUDIO_CHANNEL_POSITION_SIDE_RIGHT:
return "SR";
case GST_AUDIO_CHANNEL_POSITION_TOP_FRONT_LEFT:
return "TFL";
case GST_AUDIO_CHANNEL_POSITION_TOP_FRONT_RIGHT:
return "TFR";
case GST_AUDIO_CHANNEL_POSITION_TOP_FRONT_CENTER:
return "TFC";
case GST_AUDIO_CHANNEL_POSITION_TOP_CENTER:
return "TFC";
case GST_AUDIO_CHANNEL_POSITION_TOP_REAR_LEFT:
return "TRL";
case GST_AUDIO_CHANNEL_POSITION_TOP_REAR_RIGHT:
return "TRR";
case GST_AUDIO_CHANNEL_POSITION_TOP_SIDE_LEFT:
return "TSL";
case GST_AUDIO_CHANNEL_POSITION_TOP_SIDE_RIGHT:
return "TSR";
case GST_AUDIO_CHANNEL_POSITION_TOP_REAR_CENTER:
return "TRC";
case GST_AUDIO_CHANNEL_POSITION_BOTTOM_FRONT_CENTER:
return "BFC";
case GST_AUDIO_CHANNEL_POSITION_BOTTOM_FRONT_LEFT:
return "BFL";
case GST_AUDIO_CHANNEL_POSITION_BOTTOM_FRONT_RIGHT:
return "BFR";
case GST_AUDIO_CHANNEL_POSITION_WIDE_LEFT:
return "WL";
case GST_AUDIO_CHANNEL_POSITION_WIDE_RIGHT:
return "WR";
case GST_AUDIO_CHANNEL_POSITION_SURROUND_LEFT:
return "SL";
case GST_AUDIO_CHANNEL_POSITION_SURROUND_RIGHT:
return "SR";
default:
break;
}
return "UNKNOWN";
}
/**
* gst_audio_channel_positions_to_string:
* @position: (array length=channels): The %GstAudioChannelPositions
* to convert.
* @channels: The number of channels.
*
* Converts @position to a human-readable string representation for
* debugging purposes.
*
* Returns: (transfer full): a newly allocated string representing
* @position
*
* Since 1.10
*/
gchar *
gst_audio_channel_positions_to_string (const GstAudioChannelPosition * position,
gint channels)
{
guint i;
GString *tmp;
g_return_val_if_fail (channels > 0, FALSE);
g_return_val_if_fail (position != NULL, FALSE);
tmp = g_string_new ("[");
for (i = 0; i < channels; i++)
g_string_append_printf (tmp, " %s", position_to_string (position[i]));
g_string_append (tmp, " ]");
return g_string_free (tmp, FALSE);
}