diff options
Diffstat (limited to 'tutorials/playback-tutorial-2.c')
| -rw-r--r-- | tutorials/playback-tutorial-2.c | 223 |
1 files changed, 223 insertions, 0 deletions
diff --git a/tutorials/playback-tutorial-2.c b/tutorials/playback-tutorial-2.c new file mode 100644 index 0000000..52d3f6f --- /dev/null +++ b/tutorials/playback-tutorial-2.c @@ -0,0 +1,223 @@ +#include <stdio.h>
+#include <gst/gst.h>
+
+/* Structure to contain all our information, so we can pass it around */
+typedef struct _CustomData {
+ GstElement *playbin; /* Our one and only element */
+
+ gint n_video; /* Number of embedded video streams */
+ gint n_audio; /* Number of embedded audio streams */
+ gint n_text; /* Number of embedded subtitle streams */
+
+ gint current_video; /* Currently playing video stream */
+ gint current_audio; /* Currently playing audio stream */
+ gint current_text; /* Currently playing subtitle stream */
+
+ GMainLoop *main_loop; /* GLib's Main Loop */
+} CustomData;
+
+/* playbin flags */
+typedef enum {
+ GST_PLAY_FLAG_VIDEO = (1 << 0), /* We want video output */
+ GST_PLAY_FLAG_AUDIO = (1 << 1), /* We want audio output */
+ GST_PLAY_FLAG_TEXT = (1 << 2) /* We want subtitle output */
+} GstPlayFlags;
+
+/* Forward definition for the message and keyboard processing functions */
+static gboolean handle_message (GstBus *bus, GstMessage *msg, CustomData *data);
+static gboolean handle_keyboard (GIOChannel *source, GIOCondition cond, CustomData *data);
+
+int main(int argc, char *argv[]) {
+ CustomData data;
+ GstBus *bus;
+ GstStateChangeReturn ret;
+ gint flags;
+ GIOChannel *io_stdin;
+
+ /* Initialize GStreamer */
+ gst_init (&argc, &argv);
+
+ /* Create the elements */
+ data.playbin = gst_element_factory_make ("playbin", "playbin");
+
+ if (!data.playbin) {
+ g_printerr ("Not all elements could be created.\n");
+ return -1;
+ }
+
+ /* Set the URI to play */
+ g_object_set (data.playbin, "uri", "https://www.freedesktop.org/software/gstreamer-sdk/data/media/sintel_trailer-480p.ogv", NULL);
+
+ /* Set the subtitle URI to play and some font description */
+ g_object_set (data.playbin, "suburi", "https://www.freedesktop.org/software/gstreamer-sdk/data/media/sintel_trailer_gr.srt", NULL);
+ g_object_set (data.playbin, "subtitle-font-desc", "Sans, 18", NULL);
+
+ /* Set flags to show Audio, Video and Subtitles */
+ g_object_get (data.playbin, "flags", &flags, NULL);
+ flags |= GST_PLAY_FLAG_VIDEO | GST_PLAY_FLAG_AUDIO | GST_PLAY_FLAG_TEXT;
+ g_object_set (data.playbin, "flags", flags, NULL);
+
+ /* Add a bus watch, so we get notified when a message arrives */
+ bus = gst_element_get_bus (data.playbin);
+ gst_bus_add_watch (bus, (GstBusFunc)handle_message, &data);
+
+ /* Add a keyboard watch so we get notified of keystrokes */
+#ifdef G_OS_WIN32
+ io_stdin = g_io_channel_win32_new_fd (fileno (stdin));
+#else
+ io_stdin = g_io_channel_unix_new (fileno (stdin));
+#endif
+ g_io_add_watch (io_stdin, G_IO_IN, (GIOFunc)handle_keyboard, &data);
+
+ /* Start playing */
+ ret = gst_element_set_state (data.playbin, GST_STATE_PLAYING);
+ if (ret == GST_STATE_CHANGE_FAILURE) {
+ g_printerr ("Unable to set the pipeline to the playing state.\n");
+ gst_object_unref (data.playbin);
+ return -1;
+ }
+
+ /* Create a GLib Main Loop and set it to run */
+ data.main_loop = g_main_loop_new (NULL, FALSE);
+ g_main_loop_run (data.main_loop);
+
+ /* Free resources */
+ g_main_loop_unref (data.main_loop);
+ g_io_channel_unref (io_stdin);
+ gst_object_unref (bus);
+ gst_element_set_state (data.playbin, GST_STATE_NULL);
+ gst_object_unref (data.playbin);
+ return 0;
+}
+
+/* Extract some metadata from the streams and print it on the screen */
+static void analyze_streams (CustomData *data) {
+ gint i;
+ GstTagList *tags;
+ gchar *str;
+ guint rate;
+
+ /* Read some properties */
+ g_object_get (data->playbin, "n-video", &data->n_video, NULL);
+ g_object_get (data->playbin, "n-audio", &data->n_audio, NULL);
+ g_object_get (data->playbin, "n-text", &data->n_text, NULL);
+
+ g_print ("%d video stream(s), %d audio stream(s), %d text stream(s)\n",
+ data->n_video, data->n_audio, data->n_text);
+
+ g_print ("\n");
+ for (i = 0; i < data->n_video; i++) {
+ tags = NULL;
+ /* Retrieve the stream's video tags */
+ g_signal_emit_by_name (data->playbin, "get-video-tags", i, &tags);
+ if (tags) {
+ g_print ("video stream %d:\n", i);
+ gst_tag_list_get_string (tags, GST_TAG_VIDEO_CODEC, &str);
+ g_print (" codec: %s\n", str ? str : "unknown");
+ g_free (str);
+ gst_tag_list_free (tags);
+ }
+ }
+
+ g_print ("\n");
+ for (i = 0; i < data->n_audio; i++) {
+ tags = NULL;
+ /* Retrieve the stream's audio tags */
+ g_signal_emit_by_name (data->playbin, "get-audio-tags", i, &tags);
+ if (tags) {
+ g_print ("audio stream %d:\n", i);
+ if (gst_tag_list_get_string (tags, GST_TAG_AUDIO_CODEC, &str)) {
+ g_print (" codec: %s\n", str);
+ g_free (str);
+ }
+ if (gst_tag_list_get_string (tags, GST_TAG_LANGUAGE_CODE, &str)) {
+ g_print (" language: %s\n", str);
+ g_free (str);
+ }
+ if (gst_tag_list_get_uint (tags, GST_TAG_BITRATE, &rate)) {
+ g_print (" bitrate: %d\n", rate);
+ }
+ gst_tag_list_free (tags);
+ }
+ }
+
+ g_print ("\n");
+ for (i = 0; i < data->n_text; i++) {
+ tags = NULL;
+ /* Retrieve the stream's subtitle tags */
+ g_print ("subtitle stream %d:\n", i);
+ g_signal_emit_by_name (data->playbin, "get-text-tags", i, &tags);
+ if (tags) {
+ if (gst_tag_list_get_string (tags, GST_TAG_LANGUAGE_CODE, &str)) {
+ g_print (" language: %s\n", str);
+ g_free (str);
+ }
+ gst_tag_list_free (tags);
+ } else {
+ g_print (" no tags found\n");
+ }
+ }
+
+ g_object_get (data->playbin, "current-video", &data->current_video, NULL);
+ g_object_get (data->playbin, "current-audio", &data->current_audio, NULL);
+ g_object_get (data->playbin, "current-text", &data->current_text, NULL);
+
+ g_print ("\n");
+ g_print ("Currently playing video stream %d, audio stream %d and subtitle stream %d\n",
+ data->current_video, data->current_audio, data->current_text);
+ g_print ("Type any number and hit ENTER to select a different subtitle stream\n");
+}
+
+/* Process messages from GStreamer */
+static gboolean handle_message (GstBus *bus, GstMessage *msg, CustomData *data) {
+ GError *err;
+ gchar *debug_info;
+
+ switch (GST_MESSAGE_TYPE (msg)) {
+ case GST_MESSAGE_ERROR:
+ gst_message_parse_error (msg, &err, &debug_info);
+ g_printerr ("Error received from element %s: %s\n", GST_OBJECT_NAME (msg->src), err->message);
+ g_printerr ("Debugging information: %s\n", debug_info ? debug_info : "none");
+ g_clear_error (&err);
+ g_free (debug_info);
+ g_main_loop_quit (data->main_loop);
+ break;
+ case GST_MESSAGE_EOS:
+ g_print ("End-Of-Stream reached.\n");
+ g_main_loop_quit (data->main_loop);
+ break;
+ case GST_MESSAGE_STATE_CHANGED: {
+ GstState old_state, new_state, pending_state;
+ gst_message_parse_state_changed (msg, &old_state, &new_state, &pending_state);
+ if (GST_MESSAGE_SRC (msg) == GST_OBJECT (data->playbin)) {
+ if (new_state == GST_STATE_PLAYING) {
+ /* Once we are in the playing state, analyze the streams */
+ analyze_streams (data);
+ }
+ }
+ } break;
+ default:
+ break;
+ }
+
+ /* We want to keep receiving messages */
+ return TRUE;
+}
+
+/* Process keyboard input */
+static gboolean handle_keyboard (GIOChannel *source, GIOCondition cond, CustomData *data) {
+ gchar *str = NULL;
+
+ if (g_io_channel_read_line (source, &str, NULL, NULL, NULL) == G_IO_STATUS_NORMAL) {
+ int index = g_ascii_strtoull (str, NULL, 0);
+ if (index < 0 || index >= data->n_text) {
+ g_printerr ("Index out of bounds\n");
+ } else {
+ /* If the input was a valid subtitle stream index, set the current subtitle stream */
+ g_print ("Setting current subtitle stream to %d\n", index);
+ g_object_set (data->playbin, "current-text", index, NULL);
+ }
+ }
+ g_free (str);
+ return TRUE;
+}
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