gstreamer/examples/metadata/read-metadata.c

250 lines
6.5 KiB
C
Raw Normal View History

/* GStreamer
* Copyright (C) 2003 Thomas Vander Stichele <thomas@apestaart.org>
* 2003 Benjamin Otte <in7y118@public.uni-hamburg.de>
* 2005 Andy Wingo <wingo@pobox.com>
* 2005 Jan Schmidt <thaytan@mad.scientist.com>
*
* gst-metadata.c: Use GStreamer to display metadata within files.
*
* 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 <string.h>
#include <stdlib.h>
#include <locale.h>
#include <gst/gst.h>
char *filename = NULL;
GstElement *pipeline = NULL;
GstElement *source = NULL;
#define NEW_PIPE_PER_FILE
static void
message_loop (GstElement * element, GstTagList ** tags)
{
GstBus *bus;
gboolean done = FALSE;
bus = gst_element_get_bus (element);
g_return_if_fail (bus != NULL);
g_return_if_fail (tags != NULL);
while (!done) {
GstMessage *message;
GstMessageType revent;
revent = gst_bus_poll (bus, GST_MESSAGE_ANY, -1);
if (revent == GST_MESSAGE_UNKNOWN) {
/* Messages ended */
gst_object_unref (bus);
return;
}
message = gst_bus_pop (bus);
if (message == NULL)
continue;
switch (GST_MESSAGE_TYPE (message)) {
case GST_MESSAGE_EOS:
case GST_MESSAGE_ERROR:
done = TRUE;
break;
case GST_MESSAGE_TAG:
{
GstTagList *new_tags;
gst_message_parse_tag (message, &new_tags);
if (tags) {
if (*tags)
*tags =
gst_tag_list_merge (*tags, new_tags, GST_TAG_MERGE_KEEP_ALL);
else
*tags = new_tags;
} else {
GST_WARNING ("Failed to extract tags list from message");
}
break;
}
case GST_MESSAGE_APPLICATION:
{
const GstStructure *s = gst_message_get_structure (message);
/* Application specific message used to mark end point */
if (strcmp (gst_structure_get_name (s), "gst-metadata-mark") == 0)
done = TRUE;
break;
}
default:
break;
}
gst_message_unref (message);
}
gst_object_unref (bus);
}
void
have_pad_handler (GstElement * decodebin, GstPad * pad, gboolean last,
GstElement * sink)
{
GST_DEBUG ("New pad %" GST_PTR_FORMAT " - attempting link", pad);
gst_pad_link (pad, gst_element_get_pad (sink, "sink"));
}
static void
make_pipeline ()
{
GstElement *decodebin, *fakesink;
if (pipeline != NULL)
gst_object_unref (pipeline);
pipeline = gst_pipeline_new (NULL);
g_object_set (G_OBJECT (pipeline), "play-timeout",
(GstClockTime) 5 * GST_SECOND, NULL);
source = gst_element_factory_make ("filesrc", "source");
g_assert (GST_IS_ELEMENT (source));
decodebin = gst_element_factory_make ("decodebin", "decodebin");
g_assert (GST_IS_ELEMENT (decodebin));
fakesink = gst_element_factory_make ("fakesink", "fakesink");
g_assert (GST_IS_ELEMENT (fakesink));
gst_bin_add_many (GST_BIN (pipeline), source, decodebin, fakesink, NULL);
gst_element_link (source, decodebin);
/* Listen for pads from decodebin */
g_signal_connect (G_OBJECT (decodebin), "new-decoded-pad",
G_CALLBACK (have_pad_handler), fakesink);
}
static void
print_tag (const GstTagList * list, const gchar * tag, gpointer unused)
{
gint i, count;
count = gst_tag_list_get_tag_size (list, tag);
for (i = 0; i < count; i++) {
gchar *str;
if (gst_tag_get_type (tag) == G_TYPE_STRING) {
if (!gst_tag_list_get_string_index (list, tag, i, &str))
g_assert_not_reached ();
} else {
str =
g_strdup_value_contents (gst_tag_list_get_value_index (list, tag, i));
}
if (i == 0) {
g_print (" %15s: %s\n", gst_tag_get_nick (tag), str);
} else {
g_print (" : %s\n", str);
}
g_free (str);
}
}
int
main (int argc, char *argv[])
{
guint i = 1;
setlocale (LC_ALL, "");
gst_init (&argc, &argv);
if (argc < 2) {
g_print ("Please give filenames to read metadata from\n\n");
return 1;
}
make_pipeline ();
while (i < argc) {
GstStateChangeReturn sret;
GstState state;
filename = argv[i];
g_object_set (source, "location", filename, NULL);
GST_DEBUG ("Starting reading for %s", filename);
/* Decodebin will only commit to PAUSED if it actually finds a type;
* otherwise the state change fails */
sret = gst_element_set_state (GST_ELEMENT (pipeline), GST_STATE_PAUSED);
if (GST_STATE_CHANGE_ASYNC == sret) {
if (GST_STATE_CHANGE_FAILURE ==
gst_element_get_state (GST_ELEMENT (pipeline), &state, NULL, NULL)) {
g_print ("State change failed. Aborting");
break;
}
} else if (sret != GST_STATE_CHANGE_SUCCESS) {
g_print ("%s - Could not read file\n", argv[i]);
} else {
GstTagList *tags = NULL;
GstBus *bus;
/* Send message on the bus to mark end point of preroll. */
bus = gst_element_get_bus (GST_ELEMENT (pipeline));
if (bus) {
gst_bus_post (bus,
gst_message_new_application (NULL,
gst_structure_new ("gst-metadata-mark", NULL)));
gst_object_unref (bus);
}
message_loop (GST_ELEMENT (pipeline), &tags);
if (tags) {
g_print ("Metadata for %s:\n", argv[i]);
gst_tag_list_foreach (tags, print_tag, NULL);
gst_tag_list_free (tags);
tags = NULL;
} else
g_print ("No metadata found for %s\n", argv[i]);
sret = gst_element_set_state (GST_ELEMENT (pipeline), GST_STATE_NULL);
if (GST_STATE_CHANGE_ASYNC == sret) {
if (GST_STATE_CHANGE_FAILURE ==
gst_element_get_state (GST_ELEMENT (pipeline), &state, NULL, NULL))
{
g_print ("State change failed. Aborting");
break;
}
}
}
i++;
#ifdef NEW_PIPE_PER_FILE
make_pipeline ();
#endif
}
if (pipeline)
gst_object_unref (pipeline);
return 0;
}