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-rw-r--r--gst-libs/gst/audio/multichannel.c634
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diff --git a/gst-libs/gst/audio/multichannel.c b/gst-libs/gst/audio/multichannel.c
deleted file mode 100644
index 67c055d9..00000000
--- a/gst-libs/gst/audio/multichannel.c
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@@ -1,634 +0,0 @@
-/* GStreamer Multichannel-Audio helper functions
- * (c) 2004 Ronald Bultje <rbultje@ronald.bitfreak.net>
- *
- * 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., 59 Temple Place - Suite 330,
- * Boston, MA 02111-1307, USA.
- */
-
-#ifdef HAVE_CONFIG_H
-#include <config.h>
-#endif
-
-#include "multichannel.h"
-
-#define GST_AUDIO_CHANNEL_POSITIONS_PROPERTY_NAME "channel-positions"
-
-/*
- * This function checks if basic assumptions apply:
- * - does each position occur at most once?
- * - do conflicting positions occur?
- * + front_mono vs. front_left/right
- * + front_center vs. front_left/right_of_center
- * + rear_center vs. rear_left/right
- * It also adds some hacks that 0.8.x needs for compatibility:
- * - if channels == 1, are we really mono?
- * - if channels == 2, are we really stereo?
- */
-
-static gboolean
-gst_audio_check_channel_positions (const GstAudioChannelPosition * pos,
- gint channels)
-{
- gint i, n;
- struct
- {
- GstAudioChannelPosition pos1[2];
- GstAudioChannelPosition pos2[1];
- } conf[] = {
- /* front: mono <-> stereo */
- { {
- GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT,
- GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT}, {
- GST_AUDIO_CHANNEL_POSITION_FRONT_MONO}},
- /* front center: 2 <-> 1 */
- { {
- GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT_OF_CENTER,
- GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT_OF_CENTER}, {
- GST_AUDIO_CHANNEL_POSITION_FRONT_CENTER}},
- /* rear: 2 <-> 1 */
- { {
- GST_AUDIO_CHANNEL_POSITION_REAR_LEFT,
- GST_AUDIO_CHANNEL_POSITION_REAR_RIGHT}, {
- GST_AUDIO_CHANNEL_POSITION_REAR_CENTER}}, { {
- GST_AUDIO_CHANNEL_POSITION_INVALID}}
- };
-
- /* check for invalid channel positions */
- for (n = 0; n < channels; n++) {
- if (pos[n] == GST_AUDIO_CHANNEL_POSITION_INVALID) {
- g_warning ("Position %d is invalid, not allowed", n);
- return FALSE;
- }
- }
-
- /* check for multiple position occurrences */
- for (i = GST_AUDIO_CHANNEL_POSITION_INVALID + 1;
- i < GST_AUDIO_CHANNEL_POSITION_NUM; i++) {
- gint count = 0;
-
- for (n = 0; n < channels; n++) {
- if (pos[n] == i)
- count++;
- }
-
- if (count > 1) {
- g_warning ("Channel position %d occurred %d times, not allowed",
- i, count);
- return FALSE;
- }
- }
-
- /* check for position conflicts */
- for (i = 0; conf[i].pos1[0] != GST_AUDIO_CHANNEL_POSITION_INVALID; i++) {
- gboolean found1 = FALSE, found2 = FALSE;
-
- for (n = 0; n < channels; n++) {
- if (pos[n] == conf[i].pos1[0] || pos[n] == conf[i].pos1[1])
- found1 = TRUE;
- else if (pos[n] == conf[i].pos2[0])
- found2 = TRUE;
- }
-
- if (found1 && found2) {
- g_warning ("Found conflicting channel positions %d/%d and %d",
- conf[i].pos1[0], conf[i].pos1[1], conf[i].pos2[0]);
- return FALSE;
- }
- }
-
- /* 0.8.x evilry */
- if ((channels == 1 && pos[0] != GST_AUDIO_CHANNEL_POSITION_FRONT_MONO) ||
- (channels == 2 && (pos[0] != GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT ||
- pos[1] != GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT))) {
- g_warning ("0.8.x: channels=1 implies mono; channels=2 implies stereo");
- return FALSE;
- }
-
- return TRUE;
-}
-
-/**
- * gst_audio_get_channel_positions:
- * @str: A #GstStructure to retrieve channel positions from.
- *
- * Retrieves a number of (fixed!) audio channel positions from
- * the provided #GstStructure and returns it as a newly allocated
- * array. The caller should g_free () this array. The caller
- * should also check that the members in this #GstStructure are
- * indeed "fixed" before calling this function.
- *
- * Returns: a newly allocated array containing the channel
- * positions as provided in the given #GstStructure. Returns
- * NULL on error.
- */
-
-GstAudioChannelPosition *
-gst_audio_get_channel_positions (GstStructure * str)
-{
- GstAudioChannelPosition *pos;
- gint channels, n;
- const GValue *pos_val_arr, *pos_val_entry;
- gboolean res;
- GType t;
-
- /* get number of channels, general type checkups */
- g_return_val_if_fail (str != NULL, NULL);
- res = gst_structure_get_int (str, "channels", &channels);
- g_return_val_if_fail (res, NULL);
- g_return_val_if_fail (channels > 0, NULL);
- pos_val_arr = gst_structure_get_value (str,
- GST_AUDIO_CHANNEL_POSITIONS_PROPERTY_NAME);
-
- /* The following checks are here to retain compatibility for plugins not
- * implementing this property. They expect that channels=1 implies mono
- * and channels=2 implies stereo, so we follow that.
- * This might be removed during 0.9.x. */
- if (!pos_val_arr && (channels == 1 || channels == 2)) {
- pos = g_new (GstAudioChannelPosition, channels);
- if (channels == 1) {
- pos[0] = GST_AUDIO_CHANNEL_POSITION_FRONT_MONO;
- } else {
- pos[0] = GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT;
- pos[1] = GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT;
- }
- return pos;
- }
- g_return_val_if_fail (pos_val_arr != NULL, NULL);
- g_return_val_if_fail (gst_value_list_get_size (pos_val_arr) == channels,
- NULL);
- for (n = 0; n < channels; n++) {
- t = G_VALUE_TYPE (gst_value_list_get_value (pos_val_arr, n));
- g_return_val_if_fail (t == GST_TYPE_AUDIO_CHANNEL_POSITION, NULL);
- }
-
- /* ... and fill array */
- pos = g_new (GstAudioChannelPosition, channels);
- for (n = 0; n < channels; n++) {
- pos_val_entry = gst_value_list_get_value (pos_val_arr, n);
- pos[n] = g_value_get_enum (pos_val_entry);
- }
-
- if (!gst_audio_check_channel_positions (pos, channels)) {
- g_free (pos);
- return NULL;
- }
-
- return pos;
-}
-
-/**
- * gst_audio_set_channel_positions:
- * @str: A #GstStructure to retrieve channel positions from.
- * @pos: an array of channel positions. The number of members
- * in this array should be equal to the (fixed!) number
- * of the "channels" property in the given #GstStructure.
- *
- * Adds a "channel-positions" property to the given #GstStructure,
- * which will represent the channel positions as given in the
- * provided #GstAudioChannelPosition array.
- */
-
-void
-gst_audio_set_channel_positions (GstStructure * str,
- const GstAudioChannelPosition * pos)
-{
- GValue pos_val_arr = { 0 }, pos_val_entry = {
- 0};
- gint channels, n;
- gboolean res;
-
- /* get number of channels, checkups */
- g_return_if_fail (str != NULL);
- g_return_if_fail (pos != NULL);
- res = gst_structure_get_int (str, "channels", &channels);
- g_return_if_fail (res);
- g_return_if_fail (channels > 0);
- if (!gst_audio_check_channel_positions (pos, channels))
- return;
-
- /* build gvaluearray from positions */
- g_value_init (&pos_val_entry, GST_TYPE_AUDIO_CHANNEL_POSITION);
- g_value_init (&pos_val_arr, GST_TYPE_FIXED_LIST);
- for (n = 0; n < channels; n++) {
- g_value_set_enum (&pos_val_entry, pos[n]);
- gst_value_list_append_value (&pos_val_arr, &pos_val_entry);
- }
- g_value_unset (&pos_val_entry);
-
- /* add to structure */
- gst_structure_set_value (str,
- GST_AUDIO_CHANNEL_POSITIONS_PROPERTY_NAME, &pos_val_arr);
- g_value_unset (&pos_val_arr);
-}
-
-/**
- * gst_audio_set_structure_channel_positions_list:
- * @str: #GstStructure to set the list of channel positions
- * on.
- * @pos: the array containing one or more possible audio
- * channel positions that we should add in each value
- * of the array in the given structure.
- * @num_positions: the number of values in pos.
- *
- * Sets a (possibly non-fixed) list of possible audio channel
- * positions (given in pos) on the given structure. The
- * structure, after this function has been called, will contain
- * a "channel-positions" property with an array of the size of
- * the "channels" property value in the given structure (note
- * that this means that the channels property in the provided
- * structure should be fixed!). Each value in the array will
- * contain each of the values given in the pos array.
- */
-
-void
-gst_audio_set_structure_channel_positions_list (GstStructure * str,
- const GstAudioChannelPosition * pos, gint num_positions)
-{
- gint channels, n, c;
- GValue pos_val_arr = { 0 }, pos_val_list = {
- 0}, pos_val_entry = {
- 0};
- gboolean res;
-
- /* get number of channels, general type checkups */
- g_return_if_fail (str != NULL);
- g_return_if_fail (num_positions > 0);
- g_return_if_fail (pos != NULL);
- res = gst_structure_get_int (str, "channels", &channels);
- g_return_if_fail (res);
- g_return_if_fail (channels > 0);
-
- /* 0.8.x: channels=1 or channels=2 is mono/stereo, no positions needed
- * there (we discard them anyway) */
- if (channels == 1 || channels == 2)
- return;
-
- /* create the array of lists */
- g_value_init (&pos_val_arr, GST_TYPE_FIXED_LIST);
- g_value_init (&pos_val_entry, GST_TYPE_AUDIO_CHANNEL_POSITION);
- for (n = 0; n < channels; n++) {
- g_value_init (&pos_val_list, GST_TYPE_LIST);
- for (c = 0; c < num_positions; c++) {
- g_value_set_enum (&pos_val_entry, pos[c]);
- gst_value_list_append_value (&pos_val_list, &pos_val_entry);
- }
- gst_value_list_append_value (&pos_val_arr, &pos_val_list);
- g_value_unset (&pos_val_list);
- }
- g_value_unset (&pos_val_entry);
- gst_structure_set_value (str, GST_AUDIO_CHANNEL_POSITIONS_PROPERTY_NAME,
- &pos_val_arr);
- g_value_unset (&pos_val_arr);
-}
-
-/*
- * Helper function for below. The structure will be conserved,
- * but might be cut down. Any additional structures that were
- * created will be stored in the returned caps.
- */
-
-static GstCaps *
-add_list_to_struct (GstStructure * str,
- const GstAudioChannelPosition * pos, gint num_positions)
-{
- GstCaps *caps = gst_caps_new_empty ();
- const GValue *chan_val;
-
- chan_val = gst_structure_get_value (str, "channels");
- if (G_VALUE_TYPE (chan_val) == G_TYPE_INT) {
- gst_audio_set_structure_channel_positions_list (str, pos, num_positions);
- } else if (G_VALUE_TYPE (chan_val) == GST_TYPE_LIST) {
- gint size;
- const GValue *sub_val;
-
- size = gst_value_list_get_size (chan_val);
- sub_val = gst_value_list_get_value (chan_val, 0);
- gst_structure_set_value (str, "channels", sub_val);
- gst_caps_append (caps, add_list_to_struct (str, pos, num_positions));
- while (--size > 0) {
- str = gst_structure_copy (str);
- sub_val = gst_value_list_get_value (chan_val, size);
- gst_structure_set_value (str, "channels", sub_val);
- gst_caps_append (caps, add_list_to_struct (str, pos, num_positions));
- gst_caps_append_structure (caps, str);
- }
- } else if (G_VALUE_TYPE (chan_val) == GST_TYPE_INT_RANGE) {
- gint min, max;
-
- min = gst_value_get_int_range_min (chan_val);
- max = gst_value_get_int_range_max (chan_val);
-
- gst_structure_set (str, "channels", G_TYPE_INT, min, NULL);
- gst_audio_set_structure_channel_positions_list (str, pos, num_positions);
- for (++min; min < max; min++) {
- str = gst_structure_copy (str);
- gst_structure_set (str, "channels", G_TYPE_INT, min, NULL);
- gst_audio_set_structure_channel_positions_list (str, pos, num_positions);
- gst_caps_append_structure (caps, str);
- }
- } else {
- g_warning ("Unknown value type for channels property");
- }
-
- return caps;
-}
-
-/**
- * gst_audio_set_caps_channel_positions_list:
- * @caps: #GstCaps to set the list of channel positions on.
- * @pos: the array containing one or more possible audio
- * channel positions that we should add in each value
- * of the array in the given structure.
- * @num_positions: the number of values in pos.
- *
- * Sets a (possibly non-fixed) list of possible audio channel
- * positions (given in pos) on the given caps. Each of the
- * structures of the caps, after this function has been called,
- * will contain a "channel-positions" property with an array.
- * Each value in the array will contain each of the values given
- * in the pos array. Note that the size of the caps might be
- * increased by this, since each structure with a "channel-
- * positions" property needs to have a fixed "channels" property.
- * The input caps is not required to have this.
- */
-
-void
-gst_audio_set_caps_channel_positions_list (GstCaps * caps,
- const GstAudioChannelPosition * pos, gint num_positions)
-{
- gint size, n;
-
- /* get number of channels, general type checkups */
- g_return_if_fail (caps != NULL);
- g_return_if_fail (num_positions > 0);
- g_return_if_fail (pos != NULL);
-
- size = gst_caps_get_size (caps);
- for (n = 0; n < size; n++) {
- gst_caps_append (caps, add_list_to_struct (gst_caps_get_structure (caps,
- n), pos, num_positions));
- }
-}
-
-/**
- * gst_audio_fixate_channel_positions:
- * @str: a #GstStructure containing a (possibly unfixed)
- * "channel-positions" property.
- *
- * Custom fixate function. Elements that implement some sort of
- * channel conversion algorhithm should use this function for
- * fixating on GstAudioChannelPosition properties. It will take
- * care of equal channel positioning (left/right). Caller g_free()s
- * the return value. The input properties may be (and are supposed
- * to be) unfixed.
- * Note that this function is mostly a hack because we currently
- * have no way to add default fixation functions for new GTypes.
- *
- * Returns: fixed values that the caller could use as a fixed
- * set of #GstAudioChannelPosition values.
- */
-
-GstAudioChannelPosition *
-gst_audio_fixate_channel_positions (GstStructure * str)
-{
- GstAudioChannelPosition *pos;
- gint channels, n, num_unfixed = 0, i, c;
- const GValue *pos_val_arr, *pos_val_entry, *pos_val;
- gboolean res, is_stereo = TRUE;
- GType t;
-
- /*
- * We're going to do this cluelessly. We'll make an array of values that
- * conflict with each other and, for each iteration in this array, pick
- * either one until all unknown values are filled. This might not work in
- * corner cases but should work OK for the general case.
- */
- struct
- {
- GstAudioChannelPosition pos1[2];
- GstAudioChannelPosition pos2[1];
- } conf[] = {
- /* front: mono <-> stereo */
- { {
- GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT,
- GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT}, {
- GST_AUDIO_CHANNEL_POSITION_FRONT_MONO}},
- /* front center: 2 <-> 1 */
- { {
- GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT_OF_CENTER,
- GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT_OF_CENTER}, {
- GST_AUDIO_CHANNEL_POSITION_FRONT_CENTER}},
- /* rear: 2 <-> 1 */
- { {
- GST_AUDIO_CHANNEL_POSITION_REAR_LEFT,
- GST_AUDIO_CHANNEL_POSITION_REAR_RIGHT}, {
- GST_AUDIO_CHANNEL_POSITION_REAR_CENTER}}, { {
- GST_AUDIO_CHANNEL_POSITION_INVALID, GST_AUDIO_CHANNEL_POSITION_INVALID}, {
- GST_AUDIO_CHANNEL_POSITION_LFE}}, { {
- GST_AUDIO_CHANNEL_POSITION_SIDE_LEFT,
- GST_AUDIO_CHANNEL_POSITION_SIDE_RIGHT}, {
- GST_AUDIO_CHANNEL_POSITION_INVALID}}, { {
- GST_AUDIO_CHANNEL_POSITION_INVALID, GST_AUDIO_CHANNEL_POSITION_INVALID}, {
- GST_AUDIO_CHANNEL_POSITION_INVALID}}
- };
- struct
- {
- gint num_opt[3];
- guint num_opts[3];
- gboolean is_fixed[3];
- gint choice; /* -1 is none, 0 is the two, 1 is the one */
- } opt;
-
- /* get number of channels, general type checkups */
- g_return_val_if_fail (str != NULL, NULL);
- res = gst_structure_get_int (str, "channels", &channels);
- g_return_val_if_fail (res, NULL);
- g_return_val_if_fail (channels > 0, NULL);
-
- /* 0.8.x mono/stereo checks */
- pos_val_arr = gst_structure_get_value (str,
- GST_AUDIO_CHANNEL_POSITIONS_PROPERTY_NAME);
- if (!pos_val_arr && (channels == 1 || channels == 2)) {
- pos = g_new (GstAudioChannelPosition, channels);
- if (channels == 1) {
- pos[0] = GST_AUDIO_CHANNEL_POSITION_FRONT_MONO;
- } else {
- pos[0] = GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT;
- pos[1] = GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT;
- }
- return pos;
- }
- g_return_val_if_fail (pos_val_arr != NULL, NULL);
- g_return_val_if_fail (gst_value_list_get_size (pos_val_arr) == channels,
- NULL);
- for (n = 0; n < channels; n++) {
- t = G_VALUE_TYPE (gst_value_list_get_value (pos_val_arr, n));
- g_return_val_if_fail (t == GST_TYPE_LIST ||
- t == GST_TYPE_AUDIO_CHANNEL_POSITION, NULL);
- }
-
- /* all unknown, to start with */
- pos = g_new (GstAudioChannelPosition, channels);
- for (n = 0; n < channels; n++)
- pos[n] = GST_AUDIO_CHANNEL_POSITION_INVALID;
- num_unfixed = channels;
-
- /* Iterate the array of conflicting values */
- for (i = 0; conf[i].pos1[0] != GST_AUDIO_CHANNEL_POSITION_INVALID ||
- conf[i].pos2[0] != GST_AUDIO_CHANNEL_POSITION_INVALID; i++) {
- /* front/center only important if not mono (obviously) */
- if (conf[i].pos1[0] == GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT_OF_CENTER &&
- !is_stereo)
- continue;
-
- /* init values */
- for (n = 0; n < 3; n++) {
- opt.num_opt[n] = -1;
- opt.num_opts[n] = -1;
- opt.is_fixed[n] = FALSE;
- }
-
- /* Now, we'll see for each channel if it allows for any of the values in
- * the set of conflicting audio channel positions and keep scores. */
- for (n = 0; n < channels; n++) {
- /* if the channel is already taken, don't bother */
- if (pos[n] != GST_AUDIO_CHANNEL_POSITION_INVALID)
- continue;
-
- pos_val_entry = gst_value_list_get_value (pos_val_arr, n);
- t = G_VALUE_TYPE (pos_val_entry);
- if (t == GST_TYPE_LIST) {
- /* This algorhythm is suboptimal. */
- for (c = 0; c < gst_value_list_get_size (pos_val_entry); c++) {
- pos_val = gst_value_list_get_value (pos_val_entry, c);
- if (g_value_get_enum (pos_val) == conf[i].pos1[0] &&
- opt.num_opts[0] > gst_value_list_get_size (pos_val_entry) &&
- !opt.is_fixed[0]) {
- /* Now test if the old position of num_opt[0] also allows for
- * the other channel (which was skipped previously). If so,
- * keep score. */
- if (opt.num_opt[0] != -1) {
- gint c1;
-
- pos_val_entry = gst_value_list_get_value (pos_val_arr,
- opt.num_opt[0]);
- if (G_VALUE_TYPE (pos_val_entry) == GST_TYPE_LIST) {
- for (c1 = 0; c1 < gst_value_list_get_size (pos_val_entry); c1++) {
- pos_val = gst_value_list_get_value (pos_val_entry, c1);
- if (g_value_get_enum (pos_val) == conf[i].pos1[1] &&
- opt.num_opts[1] > opt.num_opts[0] && !opt.is_fixed[1]) {
- opt.num_opts[1] = opt.num_opts[0];
- opt.num_opt[1] = opt.num_opt[0];
- }
- }
- pos_val = gst_value_list_get_value (pos_val_entry, c);
- }
- pos_val_entry = gst_value_list_get_value (pos_val_arr, n);
- }
-
- /* and save values */
- opt.num_opts[0] = gst_value_list_get_size (pos_val_entry);
- opt.num_opt[0] = n;
- } else if (g_value_get_enum (pos_val) == conf[i].pos1[1] &&
- opt.num_opts[1] > gst_value_list_get_size (pos_val_entry) &&
- !opt.is_fixed[1] && n != opt.num_opt[0]) {
- opt.num_opts[1] = gst_value_list_get_size (pos_val_entry);
- opt.num_opt[1] = n;
- }
-
- /* 2 goes separately, because 0/1 vs. 2 are separate */
- if (g_value_get_enum (pos_val) == conf[i].pos2[0] &&
- opt.num_opts[2] > gst_value_list_get_size (pos_val_entry) &&
- !opt.is_fixed[2]) {
- opt.num_opts[2] = gst_value_list_get_size (pos_val_entry);
- opt.num_opt[2] = n;
- }
- }
- } else {
- if (g_value_get_enum (pos_val_entry) == conf[i].pos1[0]) {
- opt.num_opt[0] = n;
- opt.is_fixed[0] = TRUE;
- } else if (g_value_get_enum (pos_val_entry) == conf[i].pos1[1]) {
- opt.num_opt[1] = n;
- opt.is_fixed[1] = TRUE;
- } else if (g_value_get_enum (pos_val_entry) == conf[i].pos2[0]) {
- opt.num_opt[2] = n;
- opt.is_fixed[2] = TRUE;
- }
- }
- }
-
- /* check our results and choose either one */
- if ((opt.is_fixed[0] || opt.is_fixed[1]) && opt.is_fixed[2]) {
- g_warning ("Pre-fixated on both %d/%d and %d - conflict!",
- conf[i].pos1[0], conf[i].pos1[1], conf[i].pos2[0]);
- g_free (pos);
- return NULL;
- } else if ((opt.is_fixed[0] && opt.num_opt[1] == -1) ||
- (opt.is_fixed[1] && opt.num_opt[0] == -1)) {
- g_warning ("Pre-fixated one side, but other side n/a of %d/%d",
- conf[i].pos1[0], conf[i].pos1[1]);
- g_free (pos);
- return NULL;
- } else if (opt.is_fixed[0] || opt.is_fixed[1]) {
- opt.choice = 0;
- } else if (opt.is_fixed[2]) {
- opt.choice = 1;
- } else if (opt.num_opt[0] != -1 && opt.num_opt[1] != -1) {
- opt.choice = 0;
- } else if (opt.num_opt[2] != -1) {
- opt.choice = 1;
- } else {
- opt.choice = -1;
- }
-
- /* stereo? Note that we keep is_stereo to TRUE if we didn't decide on
- * any arrangement. The mono/stereo channels might be handled elsewhere
- * which is clearly outside the scope of this element, so we cannot
- * know and expect the application to handle that then. */
- if (conf[i].pos2[0] == GST_AUDIO_CHANNEL_POSITION_FRONT_MONO &&
- opt.choice == 1) {
- is_stereo = FALSE;
- }
-
- /* now actually decide what we'll do and fixate on that */
- if (opt.choice == 0) {
- g_assert (conf[i].pos1[0] != GST_AUDIO_CHANNEL_POSITION_INVALID &&
- conf[i].pos1[1] != GST_AUDIO_CHANNEL_POSITION_INVALID);
- pos[opt.num_opt[0]] = conf[i].pos1[0];
- pos[opt.num_opt[1]] = conf[i].pos1[1];
- num_unfixed -= 2;
- } else if (opt.choice == 1) {
- g_assert (conf[i].pos2[0] != GST_AUDIO_CHANNEL_POSITION_INVALID);
- pos[opt.num_opt[2]] = conf[i].pos2[0];
- num_unfixed--;
- }
- }
-
- /* safety check */
- if (num_unfixed > 0) {
- g_warning ("%d unfixed channel positions left after fixation!",
- num_unfixed);
- g_free (pos);
- return NULL;
- }
-
- if (!gst_audio_check_channel_positions (pos, channels)) {
- g_free (pos);
- return NULL;
- }
-
- return pos;
-}