It also uses the knowledge gathered in the [Basic
tutorials](Basic%2Btutorials.html) regarding:
- - How to use `playbin2` to play any kind of media
+ - How to use `playbin` to play any kind of media
- How to handle network resilience problems
# Introduction
From the previous tutorials, we already have almost all necessary pieces
to build a media player. The most complex part is assembling a pipeline
which retrieves, decodes and displays the media, but we already know
-that the `playbin2` element can take care of all that for us. We only
+that the `playbin` element can take care of all that for us. We only
need to replace the manual pipeline we used in [Android tutorial 3:
Video](Android%2Btutorial%2B3%253A%2BVideo.html) with a single-element
-`playbin2` pipeline and we are good to go\!
+`playbin` pipeline and we are good to go\!
However, we can do better than. We will add a [Seek
Bar](http://developer.android.com/reference/android/widget/SeekBar.html),
### Supporting arbitrary media URIs
The C code provides the `nativeSetUri()` method so we can indicate the
-URI of the media to play. Since `playbin2` will be taking care of
+URI of the media to play. Since `playbin` will be taking care of
retrieving the media, we can use local or remote URIs indistinctly
(`file://` or `http://`, for example). From Java, though, we want to
keep track of whether the file is local or remote, because we will not
gboolean is_live; /* Live streams do not use buffering */
} CustomData;
-/* playbin2 flags */
+/* playbin flags */
typedef enum {
GST_PLAY_FLAG_TEXT = (1 << 2) /* We want subtitle output */
} GstPlayFlags;
g_main_context_push_thread_default(data->context);
/* Build pipeline */
- data->pipeline = gst_parse_launch("playbin2", &error);
+ data->pipeline = gst_parse_launch("playbin", &error);
if (error) {
gchar *message = g_strdup_printf("Unable to build pipeline: %s", error->message);
g_clear_error (&error);
GST_DEBUG ("Done finalizing");
}
-/* Set playbin2's URI */
+/* Set playbin's URI */
void gst_native_set_uri (JNIEnv* env, jobject thiz, jstring uri) {
CustomData *data = GET_CUSTOM_DATA (env, thiz, custom_data_field_id);
if (!data || !data->pipeline) return;
and
[ReleaseStringUTFChars()](http://docs.oracle.com/javase/1.5.0/docs/guide/jni/spec/functions.html#wp17294).
-`playbin2` will only care about URI changes in the READY to PAUSED state
+`playbin` will only care about URI changes in the READY to PAUSED state
change, because the new URI might need a completely different playback
pipeline (think about switching from a local Matroska file to a remote
OGG file: this would require, at least, different source and demuxing
-elements). Thus, before passing the new URI to `playbin2` we set its
+elements). Thus, before passing the new URI to `playbin` we set its
state to READY (if we were in PAUSED or PLAYING).
-`playbin2`’s URI is exposed as a common GObject property, so we simply
+`playbin`’s URI is exposed as a common GObject property, so we simply
set it with `g_object_set()`.
We then reset the clip duration, so it is re-queried later, and bring
```
We first retrieve the video sink element from the pipeline, using the
-`video-sink` property of `playbin2`, and then its sink Pad. The
+`video-sink` property of `playbin`, and then its sink Pad. The
negotiated Caps of this Pad, which we recover using
`gst_pad_get_negotiated_caps()`, are the Caps of the decoded media.
# Conclusion
-This tutorial has shown how to embed a `playbin2` pipeline into an
+This tutorial has shown how to embed a `playbin` pipeline into an
Android application. This, effectively, turns such application into a
basic media player, capable of streaming and decoding all the formats
GStreamer understands. More particularly, it has shown:
MIME type it has.
If a new media is selected, it is passed onto the native code (which
-will set the pipeline to READY, pass the URI onto `playbin2`, and bring
+will set the pipeline to READY, pass the URI onto `playbin`, and bring
the pipeline back to the previous state). The current position is also
reset, so the new clip does not start in the previous position.
realUri = QUrl::fromLocalFile(realUri).toEncoded();
}
if (!m_pipeline) {
- m_pipeline = QGst::ElementFactory::make("playbin2").dynamicCast<QGst::Pipeline>();
+ m_pipeline = QGst::ElementFactory::make("playbin").dynamicCast<QGst::Pipeline>();
if (m_pipeline) {
//let the video widget watch the pipeline for new video sinks
watchPipeline(m_pipeline);
realUri = QUrl::fromLocalFile(realUri).toEncoded();
}
if (!m_pipeline) {
- m_pipeline = QGst::ElementFactory::make("playbin2").dynamicCast<QGst::Pipeline>();
+ m_pipeline = QGst::ElementFactory::make("playbin").dynamicCast<QGst::Pipeline>();
if (m_pipeline) {
//let the video widget watch the pipeline for new video sinks
watchPipeline(m_pipeline);
Here, we first ensure that the pipeline will receive a proper URI. If
`Player::setUri()` is called with `/home/user/some/file.mp3`, the path
-is modified to `file:///home/user/some/file.mp3`. `playbin2` only
+is modified to `file:///home/user/some/file.mp3`. `playbin` only
accepts complete URIs.
The pipeline is created via `QGst::ElementFactory::make()`. The
}
```
-Finally, we tell `playbin2` what to play by setting the `uri` property:
+Finally, we tell `playbin` what to play by setting the `uri` property:
``` lang=c
m_pipeline->setProperty("uri", realUri);
- How to quickly build a pipeline from a textual description using
`gst_parse_launch()`.
- - How to create an automatic playback pipeline using `playbin2`.
+ - How to create an automatic playback pipeline using `playbin`.
- How to signal GStreamer to start playback using
`gst_element_set_state()`.
#### Examples
-Play a media file using `playbin2` (as in [Basic tutorial 1: Hello
+Play a media file using `playbin` (as in [Basic tutorial 1: Hello
world\!](Basic%2Btutorial%2B1%253A%2BHello%2Bworld%2521.html)):
```
-gst-launch-1.0 playbin2 uri=http://docs.gstreamer.com/media/sintel_trailer-480p.webm
+gst-launch-1.0 playbin uri=http://docs.gstreamer.com/media/sintel_trailer-480p.webm
```
A fully operation playback pipeline, with audio and video (more or less
-the same pipeline that `playbin2` will create
+the same pipeline that `playbin` will create
internally):
```
programs like [GraphViz](http://www.graphviz.org), that describe the
topology of your pipeline, along with the caps negotiated in each link.
-This is also very handy when using all-in-one elements like `playbin2`
+This is also very handy when using all-in-one elements like `playbin`
or `uridecodebin`, which instantiate several elements inside them. Use
the `.dot` files to learn what pipeline they have created inside (and
learn a bit of GStreamer along the way).
`GST_DEBUG_BIN_TO_DOT_FILE_WITH_TS()` macros to generate `.dot` files
at your convenience.
-Here you have an example of the kind of pipelines that playbin2
-generates. It is very complex because `playbin2` can handle many
+Here you have an example of the kind of pipelines that playbin
+generates. It is very complex because `playbin` can handle many
different cases: Your manual pipelines normally do not need to be this
long. If your manual pipeline is starting to get very big, consider
-using `playbin2`.
+using `playbin`.
## Attachments:
-[playbin2.png](attachments/327830/2424840.png) (image/png)
+[playbin.png](attachments/327830/2424840.png) (image/png)
As it turns out, this solution is already implemented in GStreamer, but
the previous tutorials have not been benefiting from it. Some elements,
-like the `queue2` and `multiqueue` found inside `playbin2`, are capable
+like the `queue2` and `multiqueue` found inside `playbin`, are capable
of building this buffer and post bus messages regarding the buffer level
(the state of the queue). An application wanting to have more network
resilience, then, should listen to these messages and pause playback if
memset (&data, 0, sizeof (data));
/* Build the pipeline */
- pipeline = gst_parse_launch ("playbin2 uri=http://docs.gstreamer.com/media/sintel_trailer-480p.webm", NULL);
+ pipeline = gst_parse_launch ("playbin uri=http://docs.gstreamer.com/media/sintel_trailer-480p.webm", NULL);
bus = gst_element_get_bus (pipeline);
/* Start playing */
To use these events, they are created and then passed onto the pipeline,
where they propagate upstream until they reach an element that can
-handle them. If an event is passed onto a bin element like `playbin2`,
+handle them. If an event is passed onto a bin element like `playbin`,
it will simply feed the event to all its sinks, which will result in
multiple seeks being performed. The common approach is to retrieve one
-of `playbin2`’s sinks through the `video-sink` or
+of `playbin`’s sinks through the `video-sink` or
`audio-sink` properties and feed the event directly into the sink.
Frame stepping is a technique that allows playing a video frame by
" 'Q' to quit\n");
/* Build the pipeline */
- data.pipeline = gst_parse_launch ("playbin2 uri=http://docs.gstreamer.com/media/sintel_trailer-480p.webm", NULL);
+ data.pipeline = gst_parse_launch ("playbin uri=http://docs.gstreamer.com/media/sintel_trailer-480p.webm", NULL);
/* Add a keyboard watch so we get notified of keystrokes */
#ifdef _WIN32
# Walkthrough
There is nothing new in the initialization code in the main function: a
-`playbin2` pipeline is instantiated, an I/O watch is installed to track
+`playbin` pipeline is instantiated, an I/O watch is installed to track
keystrokes and a GLib main loop is executed.
Then, in the keyboard handler function:
As explained in the Introduction, to avoid performing multiple Seeks,
the Event is sent to only one sink, in this case, the video sink. It is
-obtained from `playbin2` through the `video-sink` property. It is read
+obtained from `playbin` through the `video-sink` property. It is read
at this time instead at initialization time because the actual sink may
change depending on the media contents, and this won’t be known until
the pipeline is PLAYING and some media has been read.
parameters basically specify the amount to skip (1 frame in the example)
and the new rate (which we do not change).
-The video sink is grabbed from `playbin2` in case we didn’t have it yet,
+The video sink is grabbed from `playbin` in case we didn’t have it yet,
just like before.
And with this we are done. When testing this tutorial, keep in mind that
<tbody>
<tr class="odd">
<td><img src="images/icons/emoticons/warning.png" width="16" height="16" /></td>
-<td><p>Changing the playback rate might only work with local files. If you cannot modify it, try changing the URI passed to <code>playbin2</code> in line 114 to a local URI, starting with <code>file:///</code></p></td>
+<td><p>Changing the playback rate might only work with local files. If you cannot modify it, try changing the URI passed to <code>playbin</code> in line 114 to a local URI, starting with <code>file:///</code></p></td>
</tr>
</tbody>
</table>
This tutorial gives a list of handy GStreamer elements that are worth
knowing. They range from powerful all-in-one elements that allow you to
-build complex pipelines easily (like `playbin2`), to little helper
+build complex pipelines easily (like `playbin`), to little helper
elements which are extremely useful when debugging.
For simplicity, the following examples are given using the
care of instantiating all the necessary internal pipeline to accomplish
their task.
-### `playbin2`
+### `playbin`
This element has been extensively used throughout the tutorials. It
manages all aspects of media playback, from source to display, passing
As a rule of thumb, prefer `queue2` over `queue` whenever network
buffering is a concern to you. See [Basic tutorial 12:
Streaming](Basic%2Btutorial%2B12%253A%2BStreaming.html) for an example
-(`queue2` is hidden inside `playbin2`).
+(`queue2` is hidden inside `playbin`).
### `multiqueue`
g_signal_connect (texture, "size-change", G_CALLBACK (size_change), NULL);
/* Build the GStreamer pipeline */
- pipeline = gst_parse_launch ("playbin2 uri=http://docs.gstreamer.com/media/sintel_trailer-480p.webm", NULL);
+ pipeline = gst_parse_launch ("playbin uri=http://docs.gstreamer.com/media/sintel_trailer-480p.webm", NULL);
/* Instantiate the Clutter sink */
sink = gst_element_factory_make ("autocluttersink", NULL);
g_object_set (pipeline, "video-sink", sink, NULL);
```
-Finally, tell `playbin2` to use the sink we created instead of the
+Finally, tell `playbin` to use the sink we created instead of the
default one.
Then the GStreamer pipeline and the Clutter timeline are started and the
are available on all platforms. For example, the audio and video sinks
depend heavily on the underlying windowing system, and a different one
needs to be selected depending on the platform. You normally do not need
-to worry about this when using elements like `playbin2` or
+to worry about this when using elements like `playbin` or
`autovideosink`, but, for those cases when you need to use one of the
sinks that are only available on specific platforms, this tutorial hints
you some of their peculiarities.
Source element to read iOS assets, this is, documents stored in the
Library (like photos, music and videos). It can be instantiated
-automatically by `playbin2` when URIs use the
+automatically by `playbin` when URIs use the
`assets-library://` scheme.
### `iosavassetsrc`
Source element to read and decode iOS audiovisual assets, this is,
documents stored in the Library (like photos, music and videos). It can
-be instantiated automatically by `playbin2` when URIs use the
+be instantiated automatically by `playbin` when URIs use the
`ipod-library://` scheme. Decoding is performed by the system, so
dedicated hardware will be used if available.
This tutorial has shown a few specific details about some GStreamer
elements which are not available on all platforms. You do not have to
-worry about them when using multiplatform elements like `playbin2` or
+worry about them when using multiplatform elements like `playbin` or
`autovideosink`, but it is good to know their personal quirks if
instancing them manually.
You should now see (and hear) the same movie as in [Basic tutorial 1:
Hello world!](Basic+tutorial+1+Hello+world.markdown). In
-that tutorial you used `playbin2`, which is a handy element that
+that tutorial you used `playbin`, which is a handy element that
automatically takes care of all the demuxing and pad linking for you.
Most of the [Playback tutorials](Playback+tutorials.markdown) are devoted
-to `playbin2`.
+to `playbin`.
## Conclusion
seeks and time-related queries in [Basic tutorial 4: Time
management](Basic+tutorial+4+Time+management.markdown) or move
to the [Playback tutorials](Playback+tutorials.markdown), and gain more
-insight about the `playbin2` element.
+insight about the `playbin` element.
Remember that attached to this page you should find the complete source
code of the tutorial and any accessory files needed to build it.
As an application developer, you will usually build pipelines by linking
elements together (to a lesser extent if you use all-in-all elements
-like `playbin2`). In this case, you need to know the *Pad Caps* (as they
+like `playbin`). In this case, you need to know the *Pad Caps* (as they
are familiarly referred to) of your elements, or, at least, know what
they are when GStreamer refuses to link two elements with a negotiation
error.
[Playback tutorial 3: Short-cutting the
pipeline](Playback+tutorial+3+Short-cutting+the+pipeline.markdown) explains
-how to achieve the same goals in a playbin2-based pipeline.
+how to achieve the same goals in a playbin-based pipeline.
## Introduction
Once we have the buffer ready, we pass it to `appsrc` with the
`push-buffer` action signal (see information box at the end of [Playback
-tutorial 1: Playbin2
-usage](Playback+tutorial+1+Playbin2+usage.markdown)), and then
+tutorial 1: Playbin
+usage](Playback+tutorial+1+Playbin+usage.markdown)), and then
`gst_buffer_unref()` it since we no longer need it.
``` lang=c
- Retrieve data from a pipeline using the `appsink` element.
- Manipulate this data by accessing the `GstBuffer`.
-In a playbin2-based pipeline, the same goals are achieved in a slightly
+In a playbin-based pipeline, the same goals are achieved in a slightly
different way. [Playback tutorial 3: Short-cutting the
pipeline](Playback+tutorial+3+Short-cutting+the+pipeline.markdown) shows
how to do it.
--- /dev/null
+# Playback tutorial 1: Playbin usage
+
+# Goal
+
+We have already worked with the `playbin` element, which is capable of
+building a complete playback pipeline without much work on our side.
+This tutorial shows how to further customize `playbin` in case its
+default values do not suit our particular needs.
+
+We will learn:
+
+ - How to find out how many streams a file contains, and how to switch
+ among them.
+
+ - How to gather information regarding each stream.
+
+As a side note, even though its name is `playbin`, you can pronounce it
+“playbin”, since the original `playbin` element is deprecated and nobody
+should be using it.
+
+# Introduction
+
+More often than not, multiple audio, video and subtitle streams can be
+found embedded in a single file. The most common case are regular
+movies, which contain one video and one audio stream (Stereo or 5.1
+audio tracks are considered a single stream). It is also increasingly
+common to find movies with one video and multiple audio streams, to
+account for different languages. In this case, the user selects one
+audio stream, and the application will only play that one, ignoring the
+others.
+
+To be able to select the appropriate stream, the user needs to know
+certain information about them, for example, their language. This
+information is embedded in the streams in the form of “metadata”
+(annexed data), and this tutorial shows how to retrieve it.
+
+Subtitles can also be embedded in a file, along with audio and video,
+but they are dealt with in more detail in [Playback tutorial 2: Subtitle
+management](Playback%2Btutorial%2B2%253A%2BSubtitle%2Bmanagement.html).
+Finally, multiple video streams can also be found in a single file, for
+example, in DVD with multiple angles of the same scene, but they are
+somewhat rare.
+
+>  Embedding multiple streams
+> inside a single file is called “multiplexing” or “muxing”, and such file
+> is then known as a “container”. Common container formats are Matroska
+> (.mkv), Quicktime (.qt, .mov, .mp4), Ogg (.ogg) or Webm (.webm).
+>
+>
+> Retrieving the individual streams from within the container is called
+> “demultiplexing” or “demuxing”.
+
+The following code recovers the amount of streams in the file, their
+associated metadata, and allows switching the audio stream while the
+media is playing.
+
+# The multilingual player
+
+Copy this code into a text file named `playback-tutorial-1.c` (or find
+it in the SDK installation).
+
+**playback-tutorial-1.c**
+
+``` lang=c
+#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", "http://docs.gstreamer.com/media/sintel_cropped_multilingual.webm", NULL);
+
+ /* Set flags to show Audio and Video but ignore Subtitles */
+ g_object_get (data.playbin, "flags", &flags, NULL);
+ flags |= GST_PLAY_FLAG_VIDEO | GST_PLAY_FLAG_AUDIO;
+ flags &= ~GST_PLAY_FLAG_TEXT;
+ g_object_set (data.playbin, "flags", flags, NULL);
+
+ /* Set connection speed. This will affect some internal decisions of playbin */
+ g_object_set (data.playbin, "connection-speed", 56, 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 _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_signal_emit_by_name (data->playbin, "get-text-tags", i, &tags);
+ if (tags) {
+ g_print ("subtitle stream %d:\n", i);
+ 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);
+ }
+ }
+
+ 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 text stream %d\n",
+ data->current_video, data->current_audio, data->current_text);
+ g_print ("Type any number and hit ENTER to select a different audio 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;
+ }
+
+ /* 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 = atoi (str);
+ if (index < 0 || index >= data->n_audio) {
+ g_printerr ("Index out of bounds\n");
+ } else {
+ /* If the input was a valid audio stream index, set the current audio stream */
+ g_print ("Setting current audio stream to %d\n", index);
+ g_object_set (data->playbin, "current-audio", index, NULL);
+ }
+ }
+ g_free (str);
+ return TRUE;
+}
+```
+
+>  If you need help to compile this code, refer to the **Building the
+> tutorials** section for your platform: [Mac](Installing+on+Mac+OS+X.markdown) or [Windows](Installing+on+Windows)
+> or use this specific command on Linux:
+> ```gcc playback-tutorial-1.c -o playback-tutorial-1 `pkg-config --cflags --libs gstreamer-1.0` ```
+
+If you need help to run this code, refer to the **Running the
+tutorials** section for your platform:
+[Mac OS X](Installing+on+Mac+OS+X.markdown#building-the-tutorials),
+[Windows](Installing+on+Windows.markdown#running-the-tutorials), for
+[iOS](Installing+for+iOS+development.markdown#building-the-tutorials) or for
+[android](Installing+for+Android+development.markdown#building-the-tutorials).
+
+This tutorial opens a window and displays a movie, with accompanying
+audio. The media is fetched from the Internet, so the window might take
+a few seconds to appear, depending on your connection speed. The number
+of audio streams is shown in the terminal, and the user can switch from
+one to another by entering a number and pressing enter. A small delay is
+to be expected.
+
+</p>
+
+<p>
+
+Bear in mind that there is no latency management (buffering), so on slow
+connections, the movie might stop after a few seconds. See
+how <a href="http://docs.gstreamer.com/display/GstSDK/Tutorial+12%3A+Live+streaming">Tutorial
+12: Live streaming</a> solves this issue.
+
+</p>
+
+<p>
+
+</p>
+
+<p>
+
+Required libraries: <code>gstreamer-0.10</code>
+
+</p>
+
+</td>
+
+</tr>
+
+</tbody>
+
+</table>
+
+# Walkthrough
+
+``` lang=c
+/* 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;
+```
+
+We start, as usual, putting all our variables in a structure, so we can
+pass it around to functions. For this tutorial, we need the amount of
+streams of each type, and the currently playing one. Also, we are going
+to use a different mechanism to wait for messages that allows
+interactivity, so we need a GLib's main loop object.
+
+``` lang=c
+/* 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;
+```
+
+Later we are going to set some of `playbin`'s flags. We would like to
+have a handy enum that allows manipulating these flags easily, but since
+`playbin` is a plug-in and not a part of the GStreamer core, this enum
+is not available to us. The “trick” is simply to declare this enum in
+our code, as it appears in the `playbin` documentation: `GstPlayFlags`.
+GObject allows introspection, so the possible values for these flags can
+be retrieved at runtime without using this trick, but in a far more
+cumbersome
+way.
+
+``` lang=c
+/* 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);
+```
+
+Forward declarations for the two callbacks we will be using.
+`handle_message` for the GStreamer messages, as we have already seen,
+and `handle_keyboard` for key strokes, since this tutorial is
+introducing a limited amount of interactivity.
+
+We skip over the creation of the pipeline, the instantiation of
+`playbin` and pointing it to our test media through the `uri`
+property. `playbin` is in itself a pipeline, and in this case it is
+the only element in the pipeline, so we skip completely the creation of
+the pipeline, and use directly the `playbin` element.
+
+We focus on some of the other properties of `playbin`, though:
+
+``` lang=c
+/* Set flags to show Audio and Video but ignore Subtitles */
+g_object_get (data.playbin, "flags", &flags, NULL);
+flags |= GST_PLAY_FLAG_VIDEO | GST_PLAY_FLAG_AUDIO;
+flags &= ~GST_PLAY_FLAG_TEXT;
+g_object_set (data.playbin, "flags", flags, NULL);
+```
+
+`playbin`'s behavior can be changed through its `flags` property, which
+can have any combination of `GstPlayFlags`. The most interesting values
+are:
+
+| | |
+|---------------------------|------------------------------------------------------------------------------------------------------------------------------------|
+| GST_PLAY_FLAG_VIDEO | Enable video rendering. If this flag is not set, there will be no video output. |
+| GST_PLAY_FLAG_AUDIO | Enable audio rendering. If this flag is not set, there will be no audio output. |
+| GST_PLAY_FLAG_TEXT | Enable subtitle rendering. If this flag is not set, subtitles will not be shown in the video output. |
+| GST_PLAY_FLAG_VIS | Enable rendering of visualisations when there is no video stream. Playback tutorial 6: Audio visualization goes into more details. |
+| GST_PLAY_FLAG_DOWNLOAD | See Basic tutorial 12: Streaming and Playback tutorial 4: Progressive streaming. |
+| GST_PLAY_FLAG_BUFFERING | See Basic tutorial 12: Streaming and Playback tutorial 4: Progressive streaming. |
+| GST_PLAY_FLAG_DEINTERLACE | If the video content was interlaced, this flag instructs playbin to deinterlace it before displaying it. |
+
+In our case, for demonstration purposes, we are enabling audio and video
+and disabling subtitles, leaving the rest of flags to their default
+values (this is why we read the current value of the flags with
+`g_object_get()` before overwriting it with
+`g_object_set()`).
+
+``` lang=c
+/* Set connection speed. This will affect some internal decisions of playbin */
+g_object_set (data.playbin, "connection-speed", 56, NULL);
+```
+
+This property is not really useful in this example.
+`connection-speed` informs `playbin` of the maximum speed of our
+network connection, so, in case multiple versions of the requested media
+are available in the server, `playbin` chooses the most
+appropriate. This is mostly used in combination with streaming
+protocols like `mms` or `rtsp`.
+
+We have set all these properties one by one, but we could have all of
+them with a single call to
+`g_object_set()`:
+
+``` lang=c
+g_object_set (data.playbin, "uri", "http://docs.gstreamer.com/media/sintel_cropped_multilingual.webm", "flags", flags, "connection-speed", 56, NULL);
+```
+
+This is why `g_object_set()` requires a NULL as the last parameter.
+
+``` lang=c
+ /* Add a keyboard watch so we get notified of keystrokes */
+#ifdef _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);
+```
+
+These lines connect a callback function to the standard input (the
+keyboard). The mechanism shown here is specific to GLib, and not really
+related to GStreamer, so there is no point in going into much depth.
+Applications normally have their own way of handling user input, and
+GStreamer has little to do with it besides the Navigation interface
+discussed briefly in [Tutorial 17: DVD
+playback](http://docs.gstreamer.com/display/GstSDK/Tutorial+17%3A+DVD+playback).
+
+``` lang=c
+/* 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);
+```
+
+To allow interactivity, we will no longer poll the GStreamer bus
+manually. Instead, we create a `GMainLoop`(GLib main loop) and set it
+running with `g_main_loop_run()`. This function blocks and will not
+return until `g_main_loop_quit()` is issued. In the meantime, it will
+call the callbacks we have registered at the appropriate
+times: `handle_message` when a message appears on the bus, and
+`handle_keyboard` when the user presses any key.
+
+There is nothing new in handle\_message, except that when the pipeline
+moves to the PLAYING state, it will call the `analyze_streams` function:
+
+``` lang=c
+/* 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);
+```
+
+As the comment says, this function just gathers information from the
+media and prints it on the screen. The number of video, audio and
+subtitle streams is directly available through the `n-video`,
+`n-audio` and `n-text` properties.
+
+``` lang=c
+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);
+ }
+}
+```
+
+Now, for each stream, we want to retrieve its metadata. Metadata is
+stored as tags in a `GstTagList` structure, which is a list of data
+pieces identified by a name. The `GstTagList` associated with a stream
+can be recovered with `g_signal_emit_by_name()`, and then individual
+tags are extracted with the `gst_tag_list_get_*` functions
+like `gst_tag_list_get_string()` for
+example.
+
+<table>
+
+<tbody>
+
+<tr class="odd">
+
+<td>
+
+<img src="images/icons/emoticons/information.png" width="16" height="16" />
+
+</td>
+
+<td>
+
+<p>
+
+This rather unintuitive way of retrieving the tag list is called an
+Action Signal. Action signals are emitted by the application to a
+specific element, which then performs an action and returns a result.
+They behave like a dynamic function call, in which methods of a class
+are identified by their name (the signal's name) instead of their memory
+address. These signals are listed In the documentation along with the
+regular signals, and are tagged “Action”. See <code>playbin</code>, for
+example.
+
+</p>
+
+</td>
+
+</tr>
+
+</tbody>
+
+</table>
+
+`playbin` defines 3 action signals to retrieve
+metadata: `get-video-tags`, `get-audio-tags` and `get-text-tags`. The
+name if the tags is standardized, and the list can be found in the
+`GstTagList` documentation. In this example we are interested in the
+`GST_TAG_LANGUAGE_CODE` of the streams and their
+`GST_TAG_*_CODEC` (audio, video or
+text).
+
+``` lang=c
+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);
+```
+
+Once we have extracted all the metadata we want, we get the streams that
+are currently selected through 3 more properties of `playbin`:
+`current-video`, `current-audio` and `current-text`.
+
+It is interesting to always check the currently selected streams and
+never make any assumption. Multiple internal conditions can make
+`playbin` behave differently in different executions. Also, the order
+in which the streams are listed can change from one run to another, so
+checking the metadata to identify one particular stream becomes crucial.
+
+``` lang=c
+/* 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 = atoi (str);
+ if (index < 0 || index >= data->n_audio) {
+ g_printerr ("Index out of bounds\n");
+ } else {
+ /* If the input was a valid audio stream index, set the current audio stream */
+ g_print ("Setting current audio stream to %d\n", index);
+ g_object_set (data->playbin, "current-audio", index, NULL);
+ }
+ }
+ g_free (str);
+ return TRUE;
+}
+```
+
+Finally, we allow the user to switch the running audio stream. This very
+basic function just reads a string from the standard input (the
+keyboard), interprets it as a number, and tries to set the
+`current-audio` property of `playbin` (which previously we have only
+read).
+
+Bear in mind that the switch is not immediate. Some of the previously
+decoded audio will still be flowing through the pipeline, while the new
+stream becomes active and is decoded. The delay depends on the
+particular multiplexing of the streams in the container, and the length
+`playbin` has selected for its internal queues (which depends on the
+network conditions).
+
+If you execute the tutorial, you will be able to switch from one
+language to another while the movie is running by pressing 0, 1 or 2
+(and ENTER). This concludes this tutorial.
+
+# Conclusion
+
+This tutorial has shown:
+
+ - A few more of `playbin`'s properties: `flags`, `connection-speed`,
+ `n-video`, `n-audio`, `n-text`, `current-video`, `current-audio` and
+ `current-text`.
+
+ - How to retrieve the list of tags associated with a stream
+ with `g_signal_emit_by_name()`.
+
+ - How to retrieve a particular tag from the list with
+ `gst_tag_list_get_string()`or `gst_tag_list_get_uint()`
+
+ - How to switch the current audio simply by writing to the
+ `current-audio` property.
+
+The next playback tutorial shows how to handle subtitles, either
+embedded in the container or in an external file.
+
+Remember that attached to this page you should find the complete source
+code of the tutorial and any accessory files needed to build it.
+
+It has been a pleasure having you here, and see you soon\!
+++ /dev/null
-# Playback tutorial 1: Playbin usage
-
-# Goal
-
-We have already worked with the `playbin2` element, which is capable of
-building a complete playback pipeline without much work on our side.
-This tutorial shows how to further customize `playbin2` in case its
-default values do not suit our particular needs.
-
-We will learn:
-
- - How to find out how many streams a file contains, and how to switch
- among them.
-
- - How to gather information regarding each stream.
-
-As a side note, even though its name is `playbin2`, you can pronounce it
-“playbin”, since the original `playbin` element is deprecated and nobody
-should be using it.
-
-# Introduction
-
-More often than not, multiple audio, video and subtitle streams can be
-found embedded in a single file. The most common case are regular
-movies, which contain one video and one audio stream (Stereo or 5.1
-audio tracks are considered a single stream). It is also increasingly
-common to find movies with one video and multiple audio streams, to
-account for different languages. In this case, the user selects one
-audio stream, and the application will only play that one, ignoring the
-others.
-
-To be able to select the appropriate stream, the user needs to know
-certain information about them, for example, their language. This
-information is embedded in the streams in the form of “metadata”
-(annexed data), and this tutorial shows how to retrieve it.
-
-Subtitles can also be embedded in a file, along with audio and video,
-but they are dealt with in more detail in [Playback tutorial 2: Subtitle
-management](Playback%2Btutorial%2B2%253A%2BSubtitle%2Bmanagement.html).
-Finally, multiple video streams can also be found in a single file, for
-example, in DVD with multiple angles of the same scene, but they are
-somewhat rare.
-
->  Embedding multiple streams
-> inside a single file is called “multiplexing” or “muxing”, and such file
-> is then known as a “container”. Common container formats are Matroska
-> (.mkv), Quicktime (.qt, .mov, .mp4), Ogg (.ogg) or Webm (.webm).
->
->
-> Retrieving the individual streams from within the container is called
-> “demultiplexing” or “demuxing”.
-
-The following code recovers the amount of streams in the file, their
-associated metadata, and allows switching the audio stream while the
-media is playing.
-
-# The multilingual player
-
-Copy this code into a text file named `playback-tutorial-1.c` (or find
-it in the SDK installation).
-
-**playback-tutorial-1.c**
-
-``` lang=c
-#include <gst/gst.h>
-
-/* Structure to contain all our information, so we can pass it around */
-typedef struct _CustomData {
- GstElement *playbin2; /* 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;
-
-/* playbin2 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.playbin2 = gst_element_factory_make ("playbin2", "playbin2");
-
- if (!data.playbin2) {
- g_printerr ("Not all elements could be created.\n");
- return -1;
- }
-
- /* Set the URI to play */
- g_object_set (data.playbin2, "uri", "http://docs.gstreamer.com/media/sintel_cropped_multilingual.webm", NULL);
-
- /* Set flags to show Audio and Video but ignore Subtitles */
- g_object_get (data.playbin2, "flags", &flags, NULL);
- flags |= GST_PLAY_FLAG_VIDEO | GST_PLAY_FLAG_AUDIO;
- flags &= ~GST_PLAY_FLAG_TEXT;
- g_object_set (data.playbin2, "flags", flags, NULL);
-
- /* Set connection speed. This will affect some internal decisions of playbin2 */
- g_object_set (data.playbin2, "connection-speed", 56, NULL);
-
- /* Add a bus watch, so we get notified when a message arrives */
- bus = gst_element_get_bus (data.playbin2);
- gst_bus_add_watch (bus, (GstBusFunc)handle_message, &data);
-
- /* Add a keyboard watch so we get notified of keystrokes */
-#ifdef _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.playbin2, 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.playbin2);
- 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.playbin2, GST_STATE_NULL);
- gst_object_unref (data.playbin2);
- 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->playbin2, "n-video", &data->n_video, NULL);
- g_object_get (data->playbin2, "n-audio", &data->n_audio, NULL);
- g_object_get (data->playbin2, "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->playbin2, "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->playbin2, "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_signal_emit_by_name (data->playbin2, "get-text-tags", i, &tags);
- if (tags) {
- g_print ("subtitle stream %d:\n", i);
- 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);
- }
- }
-
- g_object_get (data->playbin2, "current-video", &data->current_video, NULL);
- g_object_get (data->playbin2, "current-audio", &data->current_audio, NULL);
- g_object_get (data->playbin2, "current-text", &data->current_text, NULL);
-
- g_print ("\n");
- g_print ("Currently playing video stream %d, audio stream %d and text stream %d\n",
- data->current_video, data->current_audio, data->current_text);
- g_print ("Type any number and hit ENTER to select a different audio 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->playbin2)) {
- if (new_state == GST_STATE_PLAYING) {
- /* Once we are in the playing state, analyze the streams */
- analyze_streams (data);
- }
- }
- } 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 = atoi (str);
- if (index < 0 || index >= data->n_audio) {
- g_printerr ("Index out of bounds\n");
- } else {
- /* If the input was a valid audio stream index, set the current audio stream */
- g_print ("Setting current audio stream to %d\n", index);
- g_object_set (data->playbin2, "current-audio", index, NULL);
- }
- }
- g_free (str);
- return TRUE;
-}
-```
-
->  If you need help to compile this code, refer to the **Building the
-> tutorials** section for your platform: [Mac](Installing+on+Mac+OS+X.markdown) or [Windows](Installing+on+Windows)
-> or use this specific command on Linux:
-> ```gcc playback-tutorial-1.c -o playback-tutorial-1 `pkg-config --cflags --libs gstreamer-1.0` ```
-
-If you need help to run this code, refer to the **Running the
-tutorials** section for your platform:
-[Mac OS X](Installing+on+Mac+OS+X.markdown#building-the-tutorials),
-[Windows](Installing+on+Windows.markdown#running-the-tutorials), for
-[iOS](Installing+for+iOS+development.markdown#building-the-tutorials) or for
-[android](Installing+for+Android+development.markdown#building-the-tutorials).
-
-This tutorial opens a window and displays a movie, with accompanying
-audio. The media is fetched from the Internet, so the window might take
-a few seconds to appear, depending on your connection speed. The number
-of audio streams is shown in the terminal, and the user can switch from
-one to another by entering a number and pressing enter. A small delay is
-to be expected.
-
-</p>
-
-<p>
-
-Bear in mind that there is no latency management (buffering), so on slow
-connections, the movie might stop after a few seconds. See
-how <a href="http://docs.gstreamer.com/display/GstSDK/Tutorial+12%3A+Live+streaming">Tutorial
-12: Live streaming</a> solves this issue.
-
-</p>
-
-<p>
-
-</p>
-
-<p>
-
-Required libraries: <code>gstreamer-0.10</code>
-
-</p>
-
-</td>
-
-</tr>
-
-</tbody>
-
-</table>
-
-# Walkthrough
-
-``` lang=c
-/* Structure to contain all our information, so we can pass it around */
-typedef struct _CustomData {
- GstElement *playbin2; /* 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;
-```
-
-We start, as usual, putting all our variables in a structure, so we can
-pass it around to functions. For this tutorial, we need the amount of
-streams of each type, and the currently playing one. Also, we are going
-to use a different mechanism to wait for messages that allows
-interactivity, so we need a GLib's main loop object.
-
-``` lang=c
-/* playbin2 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;
-```
-
-Later we are going to set some of `playbin2`'s flags. We would like to
-have a handy enum that allows manipulating these flags easily, but since
-`playbin2` is a plug-in and not a part of the GStreamer core, this enum
-is not available to us. The “trick” is simply to declare this enum in
-our code, as it appears in the `playbin2` documentation: `GstPlayFlags`.
-GObject allows introspection, so the possible values for these flags can
-be retrieved at runtime without using this trick, but in a far more
-cumbersome
-way.
-
-``` lang=c
-/* 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);
-```
-
-Forward declarations for the two callbacks we will be using.
-`handle_message` for the GStreamer messages, as we have already seen,
-and `handle_keyboard` for key strokes, since this tutorial is
-introducing a limited amount of interactivity.
-
-We skip over the creation of the pipeline, the instantiation of
-`playbin2` and pointing it to our test media through the `uri`
-property. `playbin2` is in itself a pipeline, and in this case it is
-the only element in the pipeline, so we skip completely the creation of
-the pipeline, and use directly the `playbin2` element.
-
-We focus on some of the other properties of `playbin2`, though:
-
-``` lang=c
-/* Set flags to show Audio and Video but ignore Subtitles */
-g_object_get (data.playbin2, "flags", &flags, NULL);
-flags |= GST_PLAY_FLAG_VIDEO | GST_PLAY_FLAG_AUDIO;
-flags &= ~GST_PLAY_FLAG_TEXT;
-g_object_set (data.playbin2, "flags", flags, NULL);
-```
-
-`playbin2`'s behavior can be changed through its `flags` property, which
-can have any combination of `GstPlayFlags`. The most interesting values
-are:
-
-| | |
-|---------------------------|------------------------------------------------------------------------------------------------------------------------------------|
-| GST_PLAY_FLAG_VIDEO | Enable video rendering. If this flag is not set, there will be no video output. |
-| GST_PLAY_FLAG_AUDIO | Enable audio rendering. If this flag is not set, there will be no audio output. |
-| GST_PLAY_FLAG_TEXT | Enable subtitle rendering. If this flag is not set, subtitles will not be shown in the video output. |
-| GST_PLAY_FLAG_VIS | Enable rendering of visualisations when there is no video stream. Playback tutorial 6: Audio visualization goes into more details. |
-| GST_PLAY_FLAG_DOWNLOAD | See Basic tutorial 12: Streaming and Playback tutorial 4: Progressive streaming. |
-| GST_PLAY_FLAG_BUFFERING | See Basic tutorial 12: Streaming and Playback tutorial 4: Progressive streaming. |
-| GST_PLAY_FLAG_DEINTERLACE | If the video content was interlaced, this flag instructs playbin2 to deinterlace it before displaying it. |
-
-In our case, for demonstration purposes, we are enabling audio and video
-and disabling subtitles, leaving the rest of flags to their default
-values (this is why we read the current value of the flags with
-`g_object_get()` before overwriting it with
-`g_object_set()`).
-
-``` lang=c
-/* Set connection speed. This will affect some internal decisions of playbin2 */
-g_object_set (data.playbin2, "connection-speed", 56, NULL);
-```
-
-This property is not really useful in this example.
-`connection-speed` informs `playbin2` of the maximum speed of our
-network connection, so, in case multiple versions of the requested media
-are available in the server, `playbin2` chooses the most
-appropriate. This is mostly used in combination with streaming
-protocols like `mms` or `rtsp`.
-
-We have set all these properties one by one, but we could have all of
-them with a single call to
-`g_object_set()`:
-
-``` lang=c
-g_object_set (data.playbin2, "uri", "http://docs.gstreamer.com/media/sintel_cropped_multilingual.webm", "flags", flags, "connection-speed", 56, NULL);
-```
-
-This is why `g_object_set()` requires a NULL as the last parameter.
-
-``` lang=c
- /* Add a keyboard watch so we get notified of keystrokes */
-#ifdef _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);
-```
-
-These lines connect a callback function to the standard input (the
-keyboard). The mechanism shown here is specific to GLib, and not really
-related to GStreamer, so there is no point in going into much depth.
-Applications normally have their own way of handling user input, and
-GStreamer has little to do with it besides the Navigation interface
-discussed briefly in [Tutorial 17: DVD
-playback](http://docs.gstreamer.com/display/GstSDK/Tutorial+17%3A+DVD+playback).
-
-``` lang=c
-/* 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);
-```
-
-To allow interactivity, we will no longer poll the GStreamer bus
-manually. Instead, we create a `GMainLoop`(GLib main loop) and set it
-running with `g_main_loop_run()`. This function blocks and will not
-return until `g_main_loop_quit()` is issued. In the meantime, it will
-call the callbacks we have registered at the appropriate
-times: `handle_message` when a message appears on the bus, and
-`handle_keyboard` when the user presses any key.
-
-There is nothing new in handle\_message, except that when the pipeline
-moves to the PLAYING state, it will call the `analyze_streams` function:
-
-``` lang=c
-/* 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->playbin2, "n-video", &data->n_video, NULL);
- g_object_get (data->playbin2, "n-audio", &data->n_audio, NULL);
- g_object_get (data->playbin2, "n-text", &data->n_text, NULL);
-```
-
-As the comment says, this function just gathers information from the
-media and prints it on the screen. The number of video, audio and
-subtitle streams is directly available through the `n-video`,
-`n-audio` and `n-text` properties.
-
-``` lang=c
-for (i = 0; i < data->n_video; i++) {
- tags = NULL;
- /* Retrieve the stream's video tags */
- g_signal_emit_by_name (data->playbin2, "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);
- }
-}
-```
-
-Now, for each stream, we want to retrieve its metadata. Metadata is
-stored as tags in a `GstTagList` structure, which is a list of data
-pieces identified by a name. The `GstTagList` associated with a stream
-can be recovered with `g_signal_emit_by_name()`, and then individual
-tags are extracted with the `gst_tag_list_get_*` functions
-like `gst_tag_list_get_string()` for
-example.
-
-<table>
-
-<tbody>
-
-<tr class="odd">
-
-<td>
-
-<img src="images/icons/emoticons/information.png" width="16" height="16" />
-
-</td>
-
-<td>
-
-<p>
-
-This rather unintuitive way of retrieving the tag list is called an
-Action Signal. Action signals are emitted by the application to a
-specific element, which then performs an action and returns a result.
-They behave like a dynamic function call, in which methods of a class
-are identified by their name (the signal's name) instead of their memory
-address. These signals are listed In the documentation along with the
-regular signals, and are tagged “Action”. See <code>playbin2</code>, for
-example.
-
-</p>
-
-</td>
-
-</tr>
-
-</tbody>
-
-</table>
-
-`playbin2` defines 3 action signals to retrieve
-metadata: `get-video-tags`, `get-audio-tags` and `get-text-tags`. The
-name if the tags is standardized, and the list can be found in the
-`GstTagList` documentation. In this example we are interested in the
-`GST_TAG_LANGUAGE_CODE` of the streams and their
-`GST_TAG_*_CODEC` (audio, video or
-text).
-
-``` lang=c
-g_object_get (data->playbin2, "current-video", &data->current_video, NULL);
-g_object_get (data->playbin2, "current-audio", &data->current_audio, NULL);
-g_object_get (data->playbin2, "current-text", &data->current_text, NULL);
-```
-
-Once we have extracted all the metadata we want, we get the streams that
-are currently selected through 3 more properties of `playbin2`:
-`current-video`, `current-audio` and `current-text`.
-
-It is interesting to always check the currently selected streams and
-never make any assumption. Multiple internal conditions can make
-`playbin2` behave differently in different executions. Also, the order
-in which the streams are listed can change from one run to another, so
-checking the metadata to identify one particular stream becomes crucial.
-
-``` lang=c
-/* 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 = atoi (str);
- if (index < 0 || index >= data->n_audio) {
- g_printerr ("Index out of bounds\n");
- } else {
- /* If the input was a valid audio stream index, set the current audio stream */
- g_print ("Setting current audio stream to %d\n", index);
- g_object_set (data->playbin2, "current-audio", index, NULL);
- }
- }
- g_free (str);
- return TRUE;
-}
-```
-
-Finally, we allow the user to switch the running audio stream. This very
-basic function just reads a string from the standard input (the
-keyboard), interprets it as a number, and tries to set the
-`current-audio` property of `playbin2` (which previously we have only
-read).
-
-Bear in mind that the switch is not immediate. Some of the previously
-decoded audio will still be flowing through the pipeline, while the new
-stream becomes active and is decoded. The delay depends on the
-particular multiplexing of the streams in the container, and the length
-`playbin2` has selected for its internal queues (which depends on the
-network conditions).
-
-If you execute the tutorial, you will be able to switch from one
-language to another while the movie is running by pressing 0, 1 or 2
-(and ENTER). This concludes this tutorial.
-
-# Conclusion
-
-This tutorial has shown:
-
- - A few more of `playbin2`'s properties: `flags`, `connection-speed`,
- `n-video`, `n-audio`, `n-text`, `current-video`, `current-audio` and
- `current-text`.
-
- - How to retrieve the list of tags associated with a stream
- with `g_signal_emit_by_name()`.
-
- - How to retrieve a particular tag from the list with
- `gst_tag_list_get_string()`or `gst_tag_list_get_uint()`
-
- - How to switch the current audio simply by writing to the
- `current-audio` property.
-
-The next playback tutorial shows how to handle subtitles, either
-embedded in the container or in an external file.
-
-Remember that attached to this page you should find the complete source
-code of the tutorial and any accessory files needed to build it.
-
-It has been a pleasure having you here, and see you soon\!
We already know (from the previous tutorial) that container files can
hold multiple audio and video streams, and that we can very easily
choose among them by changing the `current-audio` or
-`current-video` `playbin2` property. Switching subtitles is just as
+`current-video` `playbin` property. Switching subtitles is just as
easy.
It is worth noting that, just like it happens with audio and video,
-`playbin2` takes care of choosing the right decoder for the subtitles,
+`playbin` takes care of choosing the right decoder for the subtitles,
and that the plugin structure of GStreamer allows adding support for new
formats as easily as copying a file. Everything is invisible to the
application developer.
-Besides subtitles embedded in the container, `playbin2` offers the
+Besides subtitles embedded in the container, `playbin` offers the
possibility to add an extra subtitle stream from an external URI.
This tutorial opens a file which already contains 5 subtitle streams,
/* Structure to contain all our information, so we can pass it around */
typedef struct _CustomData {
- GstElement *playbin2; /* Our one and only element */
+ GstElement *playbin; /* Our one and only element */
gint n_video; /* Number of embedded video streams */
gint n_audio; /* Number of embedded audio streams */
GMainLoop *main_loop; /* GLib's Main Loop */
} CustomData;
-/* playbin2 flags */
+/* 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_init (&argc, &argv);
/* Create the elements */
- data.playbin2 = gst_element_factory_make ("playbin2", "playbin2");
+ data.playbin = gst_element_factory_make ("playbin", "playbin");
- if (!data.playbin2) {
+ if (!data.playbin) {
g_printerr ("Not all elements could be created.\n");
return -1;
}
/* Set the URI to play */
- g_object_set (data.playbin2, "uri", "http://docs.gstreamer.com/media/sintel_trailer-480p.ogv", NULL);
+ g_object_set (data.playbin, "uri", "http://docs.gstreamer.com/media/sintel_trailer-480p.ogv", NULL);
/* Set the subtitle URI to play and some font description */
- g_object_set (data.playbin2, "suburi", "http://docs.gstreamer.com/media/sintel_trailer_gr.srt", NULL);
- g_object_set (data.playbin2, "subtitle-font-desc", "Sans, 18", NULL);
+ g_object_set (data.playbin, "suburi", "http://docs.gstreamer.com/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.playbin2, "flags", &flags, NULL);
+ 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.playbin2, "flags", flags, NULL);
+ 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.playbin2);
+ 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 */
g_io_add_watch (io_stdin, G_IO_IN, (GIOFunc)handle_keyboard, &data);
/* Start playing */
- ret = gst_element_set_state (data.playbin2, GST_STATE_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.playbin2);
+ gst_object_unref (data.playbin);
return -1;
}
g_main_loop_unref (data.main_loop);
g_io_channel_unref (io_stdin);
gst_object_unref (bus);
- gst_element_set_state (data.playbin2, GST_STATE_NULL);
- gst_object_unref (data.playbin2);
+ gst_element_set_state (data.playbin, GST_STATE_NULL);
+ gst_object_unref (data.playbin);
return 0;
}
guint rate;
/* Read some properties */
- g_object_get (data->playbin2, "n-video", &data->n_video, NULL);
- g_object_get (data->playbin2, "n-audio", &data->n_audio, NULL);
- g_object_get (data->playbin2, "n-text", &data->n_text, NULL);
+ 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);
for (i = 0; i < data->n_video; i++) {
tags = NULL;
/* Retrieve the stream's video tags */
- g_signal_emit_by_name (data->playbin2, "get-video-tags", i, &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);
for (i = 0; i < data->n_audio; i++) {
tags = NULL;
/* Retrieve the stream's audio tags */
- g_signal_emit_by_name (data->playbin2, "get-audio-tags", i, &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)) {
tags = NULL;
/* Retrieve the stream's subtitle tags */
g_print ("subtitle stream %d:\n", i);
- g_signal_emit_by_name (data->playbin2, "get-text-tags", i, &tags);
+ 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_object_get (data->playbin2, "current-video", &data->current_video, NULL);
- g_object_get (data->playbin2, "current-audio", &data->current_audio, NULL);
- g_object_get (data->playbin2, "current-text", &data->current_text, NULL);
+ 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",
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->playbin2)) {
+ 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);
} 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->playbin2, "current-text", index, NULL);
+ g_object_set (data->playbin, "current-text", index, NULL);
}
}
g_free (str);
# Walkthrough
-This tutorial is copied from [Playback tutorial 1: Playbin2
-usage](Playback%2Btutorial%2B1%253A%2BPlaybin2%2Busage.html) with some
+This tutorial is copied from [Playback tutorial 1: Playbin
+usage](Playback%2Btutorial%2B1%253A%2BPlaybin%2Busage.html) with some
changes, so let's review only the changes.
``` lang=c
/* Set the subtitle URI to play and some font description */
-g_object_set (data.playbin2, "suburi", "http://docs.gstreamer.com/media/sintel_trailer_gr.srt", NULL);
-g_object_set (data.playbin2, "subtitle-font-desc", "Sans, 18", NULL);
+g_object_set (data.playbin, "suburi", "http://docs.gstreamer.com/media/sintel_trailer_gr.srt", NULL);
+g_object_set (data.playbin, "subtitle-font-desc", "Sans, 18", NULL);
```
After setting the media URI, we set the `suburi` property, which points
-`playbin2` to a file containing a subtitle stream. In this case, the
+`playbin` to a file containing a subtitle stream. In this case, the
media file already contains multiple subtitle streams, so the one
provided in the `suburi` is added to the list, and will be the currently
selected one.
``` lang=c
/* Set flags to show Audio, Video and Subtitles */
-g_object_get (data.playbin2, "flags", &flags, NULL);
+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.playbin2, "flags", flags, NULL);
+g_object_set (data.playbin, "flags", flags, NULL);
```
We set the `flags` property to allow Audio, Video and Text (Subtitles).
-The rest of the tutorial is the same as [Playback tutorial 1: Playbin2
-usage](Playback%2Btutorial%2B1%253A%2BPlaybin2%2Busage.html), except
+The rest of the tutorial is the same as [Playback tutorial 1: Playbin
+usage](Playback%2Btutorial%2B1%253A%2BPlaybin%2Busage.html), except
that the keyboard input changes the `current-text` property instead of
the `current-audio`. As before, keep in mind that stream changes are not
immediate, since there is a lot of information flowing through the
# Conclusion
-This tutorial showed how to handle subtitles from `playbin2`, whether
+This tutorial showed how to handle subtitles from `playbin`, whether
they are embedded in the container or in a different file:
- Subtitles are chosen using the `current-tex`t and `n-tex`t
- properties of `playbin2`.
+ properties of `playbin`.
- External subtitle files can be selected using the `suburi` property.
pipeline](Basic%2Btutorial%2B8%253A%2BShort-cutting%2Bthe%2Bpipeline.html) showed
how an application can manually extract or inject data into a pipeline
by using two special elements called `appsrc` and `appsink`.
-`playbin2` allows using these elements too, but the method to connect
-them is different. To connect an `appsink` to `playbin2` see [Playback
-tutorial 7: Custom playbin2
-sinks](Playback%2Btutorial%2B7%253A%2BCustom%2Bplaybin2%2Bsinks.html).
+`playbin` allows using these elements too, but the method to connect
+them is different. To connect an `appsink` to `playbin` see [Playback
+tutorial 7: Custom playbin
+sinks](Playback%2Btutorial%2B7%253A%2BCustom%2Bplaybin%2Bsinks.html).
This tutorial shows:
- - How to connect `appsrc` with `playbin2`
+ - How to connect `appsrc` with `playbin`
- How to configure the `appsrc`
-# A playbin2 waveform generator
+# A playbin waveform generator
Copy this code into a text file named `playback-tutorial-3.c`.
g_main_loop_quit (data->main_loop);
}
-/* This function is called when playbin2 has created the appsrc element, so we have
+/* This function is called when playbin has created the appsrc element, so we have
* a chance to configure it. */
static void source_setup (GstElement *pipeline, GstElement *source, CustomData *data) {
gchar *audio_caps_text;
/* Initialize GStreamer */
gst_init (&argc, &argv);
- /* Create the playbin2 element */
- data.pipeline = gst_parse_launch ("playbin2 uri=appsrc://", NULL);
+ /* Create the playbin element */
+ data.pipeline = gst_parse_launch ("playbin uri=appsrc://", NULL);
g_signal_connect (data.pipeline, "source-setup", G_CALLBACK (source_setup), &data);
/* Instruct the bus to emit signals for each received message, and connect to the interesting signals */
```
To use an `appsrc` as the source for the pipeline, simply instantiate a
-`playbin2` and set its URI to `appsrc://`
+`playbin` and set its URI to `appsrc://`
``` lang=c
-/* Create the playbin2 element */
-data.pipeline = gst_parse_launch ("playbin2 uri=appsrc://", NULL);
+/* Create the playbin element */
+data.pipeline = gst_parse_launch ("playbin uri=appsrc://", NULL);
```
-`playbin2` will create an internal `appsrc` element and fire the
+`playbin` will create an internal `appsrc` element and fire the
`source-setup` signal to allow the application to configure
it:
```
In particular, it is important to set the caps property of `appsrc`,
-since, once the signal handler returns, `playbin2` will instantiate the
+since, once the signal handler returns, `playbin` will instantiate the
next element in the pipeline according to these
caps:
``` lang=c
-/* This function is called when playbin2 has created the appsrc element, so we have
+/* This function is called when playbin has created the appsrc element, so we have
* a chance to configure it. */
static void source_setup (GstElement *pipeline, GstElement *source, CustomData *data) {
gchar *audio_caps_text;
pipeline](Basic%2Btutorial%2B8%253A%2BShort-cutting%2Bthe%2Bpipeline.html)
for more details.
-From this point onwards, `playbin2` takes care of the rest of the
+From this point onwards, `playbin` takes care of the rest of the
pipeline, and the application only needs to worry about generating more
data when told so.
-To learn how data can be extracted from `playbin2` using the
-`appsink` element, see [Playback tutorial 7: Custom playbin2
-sinks](Playback%2Btutorial%2B7%253A%2BCustom%2Bplaybin2%2Bsinks.html).
+To learn how data can be extracted from `playbin` using the
+`appsink` element, see [Playback tutorial 7: Custom playbin
+sinks](Playback%2Btutorial%2B7%253A%2BCustom%2Bplaybin%2Bsinks.html).
# Conclusion
This tutorial applies the concepts shown in [Basic tutorial 8:
Short-cutting the
pipeline](Basic%2Btutorial%2B8%253A%2BShort-cutting%2Bthe%2Bpipeline.html) to
-`playbin2`. In particular, it has shown:
+`playbin`. In particular, it has shown:
- - How to connect `appsrc` with `playbin2` using the special
+ - How to connect `appsrc` with `playbin` using the special
URI `appsrc://`
- How to configure the `appsrc` using the `source-setup` signal
is also normally used to show how much of the file has already been
downloaded.
-`playbin2` offers similar functionalities through the `DOWNLOAD` flag
+`playbin` offers similar functionalities through the `DOWNLOAD` flag
which stores the media in a local temporary file for faster playback of
already-downloaded chunks.
#define GRAPH_LENGTH 80
-/* playbin2 flags */
+/* playbin flags */
typedef enum {
GST_PLAY_FLAG_DOWNLOAD = (1 << 7) /* Enable progressive download (on selected formats) */
} GstPlayFlags;
data.buffering_level = 100;
/* Build the pipeline */
- pipeline = gst_parse_launch ("playbin2 uri=http://docs.gstreamer.com/media/sintel_trailer-480p.webm", NULL);
+ pipeline = gst_parse_launch ("playbin uri=http://docs.gstreamer.com/media/sintel_trailer-480p.webm", NULL);
bus = gst_element_get_bus (pipeline);
/* Set the download flag */
g_object_set (pipeline, "flags", flags, NULL);
```
-By setting this flag, `playbin2` instructs its internal queue (a
+By setting this flag, `playbin` instructs its internal queue (a
`queue2` element, actually) to store all downloaded
data.
```
`deep-notify` signals are emitted by `GstObject` elements (like
-`playbin2`) when the properties of any of their children elements
+`playbin`) when the properties of any of their children elements
change. In this case we want to know when the `temp-location` property
changes, indicating that the `queue2` has decided where to store the
downloaded
The first thing we do in `refresh_ui` is construct a new Buffering
`GstQuery` with `gst_query_new_buffering()` and pass it to the pipeline
-(`playbin2`) with `gst_element_query()`. In [Basic tutorial 4: Time
+(`playbin`) with `gst_element_query()`. In [Basic tutorial 4: Time
management](Basic%2Btutorial%2B4%253A%2BTime%2Bmanagement.html) we have
already seen how to perform simple queries like Position and Duration
using specific methods. More complex queries, like Buffering, need to
This tutorial has shown:
- How to enable progressive downloading with the
- `GST_PLAY_FLAG_DOWNLOAD` `playbin2` flag
+ `GST_PLAY_FLAG_DOWNLOAD` `playbin` flag
- How to know what has been downloaded using a Buffering `GstQuery`
- How to know where it has been downloaded with the
`deep-notify::temp-location` signal
- How to limit the size of the temporary file with
- the `ring-buffer-max-size` property of `playbin2`.
+ the `ring-buffer-max-size` property of `playbin`.
It has been a pleasure having you here, and see you soon\!
them to find out if certain functionality is available, regardless of
the actual element which implements it.
-`playbin2` implements the Color Balance interface (`gstcolorbalance`),
+`playbin` implements the Color Balance interface (`gstcolorbalance`),
which allows access to the color balance settings. If any of the
-elements in the `playbin2` pipeline support this interface,
-`playbin2` simply forwards it to the application, otherwise, a
+elements in the `playbin` pipeline support this interface,
+`playbin` simply forwards it to the application, otherwise, a
colorbalance element is inserted in the pipeline.
This interface allows querying for the available color balance channels
" 'Q' to quit\n");
/* Build the pipeline */
- data.pipeline = gst_parse_launch ("playbin2 uri=http://docs.gstreamer.com/media/sintel_trailer-480p.webm", NULL);
+ data.pipeline = gst_parse_launch ("playbin uri=http://docs.gstreamer.com/media/sintel_trailer-480p.webm", NULL);
/* Add a keyboard watch so we get notified of keystrokes */
#ifdef _WIN32
# Walkthrough
-The `main()` function is fairly simple. A `playbin2` pipeline is
+The `main()` function is fairly simple. A `playbin` pipeline is
instantiated and set to run, and a keyboard watch is installed so
keystrokes can be monitored.
# Introduction
-Enabling audio visualization in `playbin2` is actually very easy. Just
-set the appropriate `playbin2` flag and, when an audio-only stream is
+Enabling audio visualization in `playbin` is actually very easy. Just
+set the appropriate `playbin` flag and, when an audio-only stream is
found, it will instantiate the necessary elements to create and display
the visualization.
If you want to specify the actual element that you want to use to
generate the visualization, you instantiate it yourself and then tell
-`playbin2` about it through the `vis-plugin` property.
+`playbin` about it through the `vis-plugin` property.
This tutorial searches the GStreamer registry for all the elements of
the Visualization class, tries to select `goom` (or another one if it is
-not available) and passes it to `playbin2`.
+not available) and passes it to `playbin`.
# A fancy music player
``` lang=c
#include <gst/gst.h>
-/* playbin2 flags */
+/* playbin flags */
typedef enum {
GST_PLAY_FLAG_VIS = (1 << 3) /* Enable rendering of visualizations when there is no video stream. */
} GstPlayFlags;
return -1;
/* Build the pipeline */
- pipeline = gst_parse_launch ("playbin2 uri=http://radio.hbr1.com:19800/ambient.ogg", NULL);
+ pipeline = gst_parse_launch ("playbin uri=http://radio.hbr1.com:19800/ambient.ogg", NULL);
/* Set the visualization flag */
g_object_get (pipeline, "flags", &flags, NULL);
flags |= GST_PLAY_FLAG_VIS;
g_object_set (pipeline, "flags", flags, NULL);
- /* set vis plugin for playbin2 */
+ /* set vis plugin for playbin */
g_object_set (pipeline, "vis-plugin", vis_plugin, NULL);
/* Start playing */
# Walkthrough
-First off, we indicate `playbin2` that we want an audio visualization by
+First off, we indicate `playbin` that we want an audio visualization by
setting the `GST_PLAY_FLAG_VIS` flag. If the media already contains
video, this flag has no effect.
g_object_set (pipeline, "flags", flags, NULL);
```
-If no visualization plugin is enforced by the user, `playbin2` will use
+If no visualization plugin is enforced by the user, `playbin` will use
`goom` (audio visualization will be disabled if `goom` is not
available). The rest of the tutorial shows how to find out the available
-visualization elements and enforce one to `playbin2`.
+visualization elements and enforce one to `playbin`.
``` lang=c
/* Get a list of all visualization plugins */
```
The selected factory is used to instantiate an actual `GstElement` which
-is then passed to `playbin2` through the `vis-plugin` property:
+is then passed to `playbin` through the `vis-plugin` property:
``` lang=c
-/* set vis plugin for playbin2 */
+/* set vis plugin for playbin */
g_object_set (pipeline, "vis-plugin", vis_plugin, NULL);
```
This tutorial has shown:
- - How to enable Audio Visualization in `playbin2` with the
+ - How to enable Audio Visualization in `playbin` with the
`GST_PLAY_FLAG_VIS` flag
- How to enforce one particular visualization element with the
- `vis-plugin` `playbin2` property
+ `vis-plugin` `playbin` property
It has been a pleasure having you here, and see you soon\!
--- /dev/null
+# Playback tutorial 7: Custom playbin sinks
+
+# Goal
+
+`playbin` can be further customized by manually selecting its audio and
+video sinks. This allows applications to rely on `playbin` to retrieve
+and decode the media and then manage the final render/display
+themselves. This tutorial shows:
+
+ - How to replace the sinks selected by `playbin`.
+ - How to use a complex pipeline as a sink.
+
+# Introduction
+
+Two properties of `playbin` allow selecting the desired audio and video
+sinks: `audio-sink` and `video-sink` (respectively). The application
+only needs to instantiate the appropriate `GstElement` and pass it to
+`playbin` through these properties.
+
+This method, though, only allows using a single Element as sink. If a
+more complex pipeline is required, for example, an equalizer plus an
+audio sink, it needs to be wrapped in a Bin, so it looks to
+`playbin` as if it was a single Element.
+
+A Bin (`GstBin`) is a container that encapsulates partial pipelines so
+they can be managed as single elements. As an example, the
+`GstPipeline` we have been using in all tutorials is a type of
+`GstBin`, which does not interact with external Elements. Elements
+inside a Bin connect to external elements through Ghost Pads
+(`GstGhostPad`), this is, Pads on the surface of the Bin which simply
+forward data from an external Pad to a given Pad on an internal Element.
+
+
+
+**Figure 1:** A Bin with two Elements and one Ghost Pad.
+
+`GstBin`s are also a type of `GstElement`, so they can be used wherever
+an Element is required, in particular, as sinks for `playbin` (and they
+are then known as **sink-bins**).
+
+# An equalized player
+
+Copy this code into a text file named `playback-tutorial-7.c`.
+
+<table>
+<tbody>
+<tr class="odd">
+<td><img src="images/icons/emoticons/information.png" width="16" height="16" /></td>
+<td><p>This tutorial is included in the SDK since release 2012.7. If you cannot find it in the downloaded code, please install the latest release of the GStreamer SDK.</p></td>
+</tr>
+</tbody>
+</table>
+
+**playback-tutorial7.c**
+
+``` lang=c
+#include <gst/gst.h>
+
+int main(int argc, char *argv[]) {
+ GstElement *pipeline, *bin, *equalizer, *convert, *sink;
+ GstPad *pad, *ghost_pad;
+ GstBus *bus;
+ GstMessage *msg;
+
+ /* Initialize GStreamer */
+ gst_init (&argc, &argv);
+
+ /* Build the pipeline */
+ pipeline = gst_parse_launch ("playbin uri=http://docs.gstreamer.com/media/sintel_trailer-480p.webm", NULL);
+
+ /* Create the elements inside the sink bin */
+ equalizer = gst_element_factory_make ("equalizer-3bands", "equalizer");
+ convert = gst_element_factory_make ("audioconvert", "convert");
+ sink = gst_element_factory_make ("autoaudiosink", "audio_sink");
+ if (!equalizer || !convert || !sink) {
+ g_printerr ("Not all elements could be created.\n");
+ return -1;
+ }
+
+ /* Create the sink bin, add the elements and link them */
+ bin = gst_bin_new ("audio_sink_bin");
+ gst_bin_add_many (GST_BIN (bin), equalizer, convert, sink, NULL);
+ gst_element_link_many (equalizer, convert, sink, NULL);
+ pad = gst_element_get_static_pad (equalizer, "sink");
+ ghost_pad = gst_ghost_pad_new ("sink", pad);
+ gst_pad_set_active (ghost_pad, TRUE);
+ gst_element_add_pad (bin, ghost_pad);
+ gst_object_unref (pad);
+
+ /* Configure the equalizer */
+ g_object_set (G_OBJECT (equalizer), "band1", (gdouble)-24.0, NULL);
+ g_object_set (G_OBJECT (equalizer), "band2", (gdouble)-24.0, NULL);
+
+ /* Set playbin's audio sink to be our sink bin */
+ g_object_set (GST_OBJECT (pipeline), "audio-sink", bin, NULL);
+
+ /* Start playing */
+ gst_element_set_state (pipeline, GST_STATE_PLAYING);
+
+ /* Wait until error or EOS */
+ bus = gst_element_get_bus (pipeline);
+ msg = gst_bus_timed_pop_filtered (bus, GST_CLOCK_TIME_NONE, GST_MESSAGE_ERROR | GST_MESSAGE_EOS);
+
+ /* Free resources */
+ if (msg != NULL)
+ gst_message_unref (msg);
+ gst_object_unref (bus);
+ gst_element_set_state (pipeline, GST_STATE_NULL);
+ gst_object_unref (pipeline);
+ return 0;
+}
+```
+
+<table>
+<tbody>
+<tr class="odd">
+<td><img src="images/icons/emoticons/information.png" width="16" height="16" /></td>
+<td><div id="expander-1371267928" class="expand-container">
+<div id="expander-control-1371267928" class="expand-control">
+<span class="expand-control-icon"><img src="images/icons/grey_arrow_down.gif" class="expand-control-image" /></span><span class="expand-control-text">Need help? (Click to expand)</span>
+</div>
+<div id="expander-content-1371267928" class="expand-content">
+<p>If you need help to compile this code, refer to the <strong>Building the tutorials</strong> section for your platform: <a href="Installing%2Bon%2BLinux.html#InstallingonLinux-Build">Linux</a>, <a href="Installing%2Bon%2BMac%2BOS%2BX.html#InstallingonMacOSX-Build">Mac OS X</a> or <a href="Installing%2Bon%2BWindows.html#InstallingonWindows-Build">Windows</a>, or use this specific command on Linux:</p>
+<div class="panel" style="border-width: 1px;">
+<div class="panelContent">
+<p><code>gcc playback-tutorial-7.c -o playback-tutorial-7 `pkg-config --cflags --libs gstreamer-0.10`</code></p>
+</div>
+</div>
+<p>If you need help to run this code, refer to the <strong>Running the tutorials</strong> section for your platform: <a href="Installing%2Bon%2BLinux.html#InstallingonLinux-Run">Linux</a>, <a href="Installing%2Bon%2BMac%2BOS%2BX.html#InstallingonMacOSX-Run">Mac OS X</a> or <a href="Installing%2Bon%2BWindows.html#InstallingonWindows-Run">Windows</a></p>
+<p><span>This tutorial opens a window and displays a movie, with accompanying audio. The media is fetched from the Internet, so the window might take a few seconds to appear, depending on your connection speed. The higher frequency bands have been attenuated, so the movie sound should have a more powerful bass component.</span></p>
+<p>Required libraries: <code>gstreamer-0.10</code></p>
+</div>
+</div></td>
+</tr>
+</tbody>
+</table>
+
+# Walkthrough
+
+``` lang=c
+/* Create the elements inside the sink bin */
+equalizer = gst_element_factory_make ("equalizer-3bands", "equalizer");
+convert = gst_element_factory_make ("audioconvert", "convert");
+sink = gst_element_factory_make ("autoaudiosink", "audio_sink");
+if (!equalizer || !convert || !sink) {
+ g_printerr ("Not all elements could be created.\n");
+ return -1;
+}
+```
+
+All the Elements that compose our sink-bin are instantiated. We use an
+`equalizer-3bands` and an `autoaudiosink`, with an `audioconvert` in
+between, because we are not sure of the capabilities of the audio sink
+(since they are hardware-dependant).
+
+``` lang=c
+/* Create the sink bin, add the elements and link them */
+bin = gst_bin_new ("audio_sink_bin");
+gst_bin_add_many (GST_BIN (bin), equalizer, convert, sink, NULL);
+gst_element_link_many (equalizer, convert, sink, NULL);
+```
+
+This adds the new Elements to the Bin and links them just as we would do
+if this was a pipeline.
+
+``` lang=c
+pad = gst_element_get_static_pad (equalizer, "sink");
+ghost_pad = gst_ghost_pad_new ("sink", pad);
+gst_pad_set_active (ghost_pad, TRUE);
+gst_element_add_pad (bin, ghost_pad);
+gst_object_unref (pad);
+```
+
+Now we need to create a Ghost Pad so this partial pipeline inside the
+Bin can be connected to the outside. This Ghost Pad will be connected to
+a Pad in one of the internal Elements (the sink pad of the equalizer),
+so we retrieve this Pad with `gst_element_get_static_pad()`. Remember
+from [Basic tutorial 7: Multithreading and Pad
+Availability](Basic%2Btutorial%2B7%253A%2BMultithreading%2Band%2BPad%2BAvailability.html) that
+if this was a Request Pad instead of an Always Pad, we would need to use
+`gst_element_request_pad()`.
+
+The Ghost Pad is created with `gst_ghost_pad_new()` (pointing to the
+inner Pad we just acquired), and activated with `gst_pad_set_active()`.
+It is then added to the Bin with `gst_element_add_pad()`, transferring
+ownership of the Ghost Pad to the bin, so we do not have to worry about
+releasing it.
+
+Finally, the sink Pad we obtained from the equalizer needs to be release
+with `gst_object_unref()`.
+
+At this point, we have a functional sink-bin, which we can use as the
+audio sink in `playbin`. We just need to instruct `playbin` to use it:
+
+``` lang=c
+/* Set playbin's audio sink to be our sink bin */
+g_object_set (GST_OBJECT (pipeline), "audio-sink", bin, NULL);
+```
+
+It is as simple as setting the `audio-sink` property on `playbin` to
+the newly created sink.
+
+``` lang=c
+/* Configure the equalizer */
+g_object_set (G_OBJECT (equalizer), "band1", (gdouble)-24.0, NULL);
+g_object_set (G_OBJECT (equalizer), "band2", (gdouble)-24.0, NULL);
+```
+
+The only bit remaining is to configure the equalizer. For this example,
+the two higher frequency bands are set to the maximum attenuation so the
+bass is boosted. Play a bit with the values to feel the difference (Look
+at the documentation for the `equalizer-3bands` element for the allowed
+range of values).
+
+# Exercise
+
+Build a video bin instead of an audio bin, using one of the many
+interesting video filters GStreamer offers, like `solarize`,
+`vertigotv` or any of the Elements in the `effectv` plugin. Remember to
+use the color space conversion element `ffmpegcolorspace` if your
+pipeline fails to link due to incompatible caps.
+
+# Conclusion
+
+This tutorial has shown:
+
+ - How to set your own sinks to `playbin` using the audio-sink and
+ video-sink properties.
+ - How to wrap a piece of pipeline into a `GstBin` so it can be used as
+ a **sink-bin** by `playbin`.
+
+It has been a pleasure having you here, and see you soon\!
+
+## Attachments:
+
+
+[bin-element-ghost.png](attachments/1441842/2424880.png) (image/png)
+
+[playback-tutorial-7.c](attachments/1441842/2424881.c) (text/plain)
+
+[vs2010.zip](attachments/1441842/2424882.zip) (application/zip)
+++ /dev/null
-# Playback tutorial 7: Custom playbin2 sinks
-
-# Goal
-
-`playbin2` can be further customized by manually selecting its audio and
-video sinks. This allows applications to rely on `playbin2` to retrieve
-and decode the media and then manage the final render/display
-themselves. This tutorial shows:
-
- - How to replace the sinks selected by `playbin2`.
- - How to use a complex pipeline as a sink.
-
-# Introduction
-
-Two properties of `playbin2` allow selecting the desired audio and video
-sinks: `audio-sink` and `video-sink` (respectively). The application
-only needs to instantiate the appropriate `GstElement` and pass it to
-`playbin2` through these properties.
-
-This method, though, only allows using a single Element as sink. If a
-more complex pipeline is required, for example, an equalizer plus an
-audio sink, it needs to be wrapped in a Bin, so it looks to
-`playbin2` as if it was a single Element.
-
-A Bin (`GstBin`) is a container that encapsulates partial pipelines so
-they can be managed as single elements. As an example, the
-`GstPipeline` we have been using in all tutorials is a type of
-`GstBin`, which does not interact with external Elements. Elements
-inside a Bin connect to external elements through Ghost Pads
-(`GstGhostPad`), this is, Pads on the surface of the Bin which simply
-forward data from an external Pad to a given Pad on an internal Element.
-
-
-
-**Figure 1:** A Bin with two Elements and one Ghost Pad.
-
-`GstBin`s are also a type of `GstElement`, so they can be used wherever
-an Element is required, in particular, as sinks for `playbin2` (and they
-are then known as **sink-bins**).
-
-# An equalized player
-
-Copy this code into a text file named `playback-tutorial-7.c`.
-
-<table>
-<tbody>
-<tr class="odd">
-<td><img src="images/icons/emoticons/information.png" width="16" height="16" /></td>
-<td><p>This tutorial is included in the SDK since release 2012.7. If you cannot find it in the downloaded code, please install the latest release of the GStreamer SDK.</p></td>
-</tr>
-</tbody>
-</table>
-
-**playback-tutorial7.c**
-
-``` lang=c
-#include <gst/gst.h>
-
-int main(int argc, char *argv[]) {
- GstElement *pipeline, *bin, *equalizer, *convert, *sink;
- GstPad *pad, *ghost_pad;
- GstBus *bus;
- GstMessage *msg;
-
- /* Initialize GStreamer */
- gst_init (&argc, &argv);
-
- /* Build the pipeline */
- pipeline = gst_parse_launch ("playbin2 uri=http://docs.gstreamer.com/media/sintel_trailer-480p.webm", NULL);
-
- /* Create the elements inside the sink bin */
- equalizer = gst_element_factory_make ("equalizer-3bands", "equalizer");
- convert = gst_element_factory_make ("audioconvert", "convert");
- sink = gst_element_factory_make ("autoaudiosink", "audio_sink");
- if (!equalizer || !convert || !sink) {
- g_printerr ("Not all elements could be created.\n");
- return -1;
- }
-
- /* Create the sink bin, add the elements and link them */
- bin = gst_bin_new ("audio_sink_bin");
- gst_bin_add_many (GST_BIN (bin), equalizer, convert, sink, NULL);
- gst_element_link_many (equalizer, convert, sink, NULL);
- pad = gst_element_get_static_pad (equalizer, "sink");
- ghost_pad = gst_ghost_pad_new ("sink", pad);
- gst_pad_set_active (ghost_pad, TRUE);
- gst_element_add_pad (bin, ghost_pad);
- gst_object_unref (pad);
-
- /* Configure the equalizer */
- g_object_set (G_OBJECT (equalizer), "band1", (gdouble)-24.0, NULL);
- g_object_set (G_OBJECT (equalizer), "band2", (gdouble)-24.0, NULL);
-
- /* Set playbin2's audio sink to be our sink bin */
- g_object_set (GST_OBJECT (pipeline), "audio-sink", bin, NULL);
-
- /* Start playing */
- gst_element_set_state (pipeline, GST_STATE_PLAYING);
-
- /* Wait until error or EOS */
- bus = gst_element_get_bus (pipeline);
- msg = gst_bus_timed_pop_filtered (bus, GST_CLOCK_TIME_NONE, GST_MESSAGE_ERROR | GST_MESSAGE_EOS);
-
- /* Free resources */
- if (msg != NULL)
- gst_message_unref (msg);
- gst_object_unref (bus);
- gst_element_set_state (pipeline, GST_STATE_NULL);
- gst_object_unref (pipeline);
- return 0;
-}
-```
-
-<table>
-<tbody>
-<tr class="odd">
-<td><img src="images/icons/emoticons/information.png" width="16" height="16" /></td>
-<td><div id="expander-1371267928" class="expand-container">
-<div id="expander-control-1371267928" class="expand-control">
-<span class="expand-control-icon"><img src="images/icons/grey_arrow_down.gif" class="expand-control-image" /></span><span class="expand-control-text">Need help? (Click to expand)</span>
-</div>
-<div id="expander-content-1371267928" class="expand-content">
-<p>If you need help to compile this code, refer to the <strong>Building the tutorials</strong> section for your platform: <a href="Installing%2Bon%2BLinux.html#InstallingonLinux-Build">Linux</a>, <a href="Installing%2Bon%2BMac%2BOS%2BX.html#InstallingonMacOSX-Build">Mac OS X</a> or <a href="Installing%2Bon%2BWindows.html#InstallingonWindows-Build">Windows</a>, or use this specific command on Linux:</p>
-<div class="panel" style="border-width: 1px;">
-<div class="panelContent">
-<p><code>gcc playback-tutorial-7.c -o playback-tutorial-7 `pkg-config --cflags --libs gstreamer-0.10`</code></p>
-</div>
-</div>
-<p>If you need help to run this code, refer to the <strong>Running the tutorials</strong> section for your platform: <a href="Installing%2Bon%2BLinux.html#InstallingonLinux-Run">Linux</a>, <a href="Installing%2Bon%2BMac%2BOS%2BX.html#InstallingonMacOSX-Run">Mac OS X</a> or <a href="Installing%2Bon%2BWindows.html#InstallingonWindows-Run">Windows</a></p>
-<p><span>This tutorial opens a window and displays a movie, with accompanying audio. The media is fetched from the Internet, so the window might take a few seconds to appear, depending on your connection speed. The higher frequency bands have been attenuated, so the movie sound should have a more powerful bass component.</span></p>
-<p>Required libraries: <code>gstreamer-0.10</code></p>
-</div>
-</div></td>
-</tr>
-</tbody>
-</table>
-
-# Walkthrough
-
-``` lang=c
-/* Create the elements inside the sink bin */
-equalizer = gst_element_factory_make ("equalizer-3bands", "equalizer");
-convert = gst_element_factory_make ("audioconvert", "convert");
-sink = gst_element_factory_make ("autoaudiosink", "audio_sink");
-if (!equalizer || !convert || !sink) {
- g_printerr ("Not all elements could be created.\n");
- return -1;
-}
-```
-
-All the Elements that compose our sink-bin are instantiated. We use an
-`equalizer-3bands` and an `autoaudiosink`, with an `audioconvert` in
-between, because we are not sure of the capabilities of the audio sink
-(since they are hardware-dependant).
-
-``` lang=c
-/* Create the sink bin, add the elements and link them */
-bin = gst_bin_new ("audio_sink_bin");
-gst_bin_add_many (GST_BIN (bin), equalizer, convert, sink, NULL);
-gst_element_link_many (equalizer, convert, sink, NULL);
-```
-
-This adds the new Elements to the Bin and links them just as we would do
-if this was a pipeline.
-
-``` lang=c
-pad = gst_element_get_static_pad (equalizer, "sink");
-ghost_pad = gst_ghost_pad_new ("sink", pad);
-gst_pad_set_active (ghost_pad, TRUE);
-gst_element_add_pad (bin, ghost_pad);
-gst_object_unref (pad);
-```
-
-Now we need to create a Ghost Pad so this partial pipeline inside the
-Bin can be connected to the outside. This Ghost Pad will be connected to
-a Pad in one of the internal Elements (the sink pad of the equalizer),
-so we retrieve this Pad with `gst_element_get_static_pad()`. Remember
-from [Basic tutorial 7: Multithreading and Pad
-Availability](Basic%2Btutorial%2B7%253A%2BMultithreading%2Band%2BPad%2BAvailability.html) that
-if this was a Request Pad instead of an Always Pad, we would need to use
-`gst_element_request_pad()`.
-
-The Ghost Pad is created with `gst_ghost_pad_new()` (pointing to the
-inner Pad we just acquired), and activated with `gst_pad_set_active()`.
-It is then added to the Bin with `gst_element_add_pad()`, transferring
-ownership of the Ghost Pad to the bin, so we do not have to worry about
-releasing it.
-
-Finally, the sink Pad we obtained from the equalizer needs to be release
-with `gst_object_unref()`.
-
-At this point, we have a functional sink-bin, which we can use as the
-audio sink in `playbin2`. We just need to instruct `playbin2` to use it:
-
-``` lang=c
-/* Set playbin2's audio sink to be our sink bin */
-g_object_set (GST_OBJECT (pipeline), "audio-sink", bin, NULL);
-```
-
-It is as simple as setting the `audio-sink` property on `playbin2` to
-the newly created sink.
-
-``` lang=c
-/* Configure the equalizer */
-g_object_set (G_OBJECT (equalizer), "band1", (gdouble)-24.0, NULL);
-g_object_set (G_OBJECT (equalizer), "band2", (gdouble)-24.0, NULL);
-```
-
-The only bit remaining is to configure the equalizer. For this example,
-the two higher frequency bands are set to the maximum attenuation so the
-bass is boosted. Play a bit with the values to feel the difference (Look
-at the documentation for the `equalizer-3bands` element for the allowed
-range of values).
-
-# Exercise
-
-Build a video bin instead of an audio bin, using one of the many
-interesting video filters GStreamer offers, like `solarize`,
-`vertigotv` or any of the Elements in the `effectv` plugin. Remember to
-use the color space conversion element `ffmpegcolorspace` if your
-pipeline fails to link due to incompatible caps.
-
-# Conclusion
-
-This tutorial has shown:
-
- - How to set your own sinks to `playbin2` using the audio-sink and
- video-sink properties.
- - How to wrap a piece of pipeline into a `GstBin` so it can be used as
- a **sink-bin** by `playbin2`.
-
-It has been a pleasure having you here, and see you soon\!
-
-## Attachments:
-
-
-[bin-element-ghost.png](attachments/1441842/2424880.png) (image/png)
-
-[playback-tutorial-7.c](attachments/1441842/2424881.c) (text/plain)
-
-[vs2010.zip](attachments/1441842/2424882.zip) (application/zip)
This all means that, if a particular hardware acceleration API is
present in the system, and the corresponding GStreamer plugin is also
-available, auto-plugging elements like `playbin2` are free to use
+available, auto-plugging elements like `playbin` are free to use
hardware acceleration to build their pipelines; the application does not
need to do anything special to enable it. Almost:
-When `playbin2` has to choose among different equally valid elements,
+When `playbin` has to choose among different equally valid elements,
like conventional software decoding (through `vp8dec`, for example) or
hardware accelerated decoding (through `vaapidecode`, for example), it
uses their *rank* to decide. The rank is a property of each element that
-indicates its priority; `playbin2` will simply select the element that
+indicates its priority; `playbin` will simply select the element that
is able to build a complete pipeline and has the highest rank.
-So, whether `playbin2` will use hardware acceleration or not will depend
+So, whether `playbin` will use hardware acceleration or not will depend
on the relative ranks of all elements capable of dealing with that media
type. Therefore, the easiest way to make sure hardware acceleration is
enabled or disabled is by changing the rank of the associated element,
- Can interface directly with Clutter (See [Basic tutorial 15: Clutter
integration](Basic%2Btutorial%2B15%253A%2BClutter%2Bintegration.html)),
so frames do not need to leave the GPU.
- - Compatible with `playbin2`.
+ - Compatible with `playbin`.
### gst-omx
- Can interface directly with Clutter (See [Basic tutorial 15: Clutter
integration](Basic%2Btutorial%2B15%253A%2BClutter%2Bintegration.html)),
so frames do not need to leave the GPU.
- - Compatible with `playbin2`.
+ - Compatible with `playbin`.
# Conclusion
system, they may also accept `audio/mpeg`, `audio/x-ac3`,
`audio/x-eac3` or `audio/x-dts`.
-Then, when `playbin2` builds the decoding pipeline, it realizes that the
+Then, when `playbin` builds the decoding pipeline, it realizes that the
audio sink can be directly connected to the encoded data (typically
coming out of a demuxer), so there is no need for a decoder. This
process is automatic and does not need any action from the application.
drivers.
Another solution involves, using a custom sinkbin (see [Playback
-tutorial 7: Custom playbin2
-sinks](Playback%2Btutorial%2B7%253A%2BCustom%2Bplaybin2%2Bsinks.html))
+tutorial 7: Custom playbin
+sinks](Playback%2Btutorial%2B7%253A%2BCustom%2Bplaybin%2Bsinks.html))
which includes a `capsfilter` element (see [Basic tutorial 14: Handy
elements](Basic%2Btutorial%2B14%253A%2BHandy%2Belements.html)) and an
audio sink. The caps that the external decoder supports are then set in
This tutorial has shown a bit of how GStreamer deals with digital audio.
In particular, it has shown that:
- - Applications using `playbin2` do not need to do anything special to
+ - Applications using `playbin` do not need to do anything special to
enable digital audio output: it is managed from the audio control
panel of the operating system.
need them. This is accessible with a simple cast:
``` lang=c
-ElementPtr qgstElement = QGst::ElementFactory::make("playbin2");
+ElementPtr qgstElement = QGst::ElementFactory::make("playbin");
GstElement* gstElement = GST_ELEMENT(qgstElement);
```
- Basic+tutorial+15+Clutter+integration.markdown
- Basic+tutorial+16+Platform-specific+elements.markdown
- Playback+tutorials.markdown
- - Playback+tutorial+1+Playbin2+usage.markdown
+ - Playback+tutorial+1+Playbin+usage.markdown
- Playback+tutorial+2+Subtitle+management.markdown
- Playback+tutorial+3+Short-cutting+the+pipeline.markdown
- Playback+tutorial+4+Progressive+streaming.markdown
- Playback+tutorial+5+Color+Balance.markdown
- Playback+tutorial+6+Audio+visualization.markdown
- - Playback+tutorial+7+Custom+playbin2+sinks.markdown
+ - Playback+tutorial+7+Custom+playbin+sinks.markdown
- Playback+tutorial+8+Hardware-accelerated+video+decoding.markdown
- Playback+tutorial+9+Digital+audio+pass-through.markdown
- Android+tutorials.markdown
- Tools: [Basic tutorial 10: GStreamer tools]
- Threads: [Basic tutorial 7: Multithreading and Pad Availability]
- [Playback tutorial 1: Playbin usage]: Playback+tutorial+1+Playbin2+usage.markdown
+ [Playback tutorial 1: Playbin usage]: Playback+tutorial+1+Playbin+usage.markdown
[Basic tutorial 8: Short-cutting the pipeline]: Basic+tutorial+8+Short-cutting+the+pipeline.markdown
[Basic tutorial 2: GStreamer concepts]: Basic+tutorial+2+GStreamer+concepts.markdown
[Basic tutorial 6: Media formats and Pad Capabilities]: Basic+tutorial+6+Media+formats+and+Pad+Capabilities.markdown
memset (&data, 0, sizeof (data));\r
\r
/* Build the pipeline */\r
- pipeline = gst_parse_launch ("playbin2 uri=http://docs.gstreamer.com/media/sintel_trailer-480p.webm", NULL);\r
+ pipeline = gst_parse_launch ("playbin uri=http://docs.gstreamer.com/media/sintel_trailer-480p.webm", NULL);\r
bus = gst_element_get_bus (pipeline);\r
\r
/* Start playing */\r
#define GRAPH_LENGTH 80
-/* playbin2 flags */
+/* playbin flags */
typedef enum {
GST_PLAY_FLAG_DOWNLOAD = (1 << 7) /* Enable progressive download (on selected formats) */
} GstPlayFlags;
data.buffering_level = 100;
/* Build the pipeline */
- pipeline = gst_parse_launch ("playbin2 uri=http://docs.gstreamer.com/media/sintel_trailer-480p.webm", NULL);
+ pipeline = gst_parse_launch ("playbin uri=http://docs.gstreamer.com/media/sintel_trailer-480p.webm", NULL);
bus = gst_element_get_bus (pipeline);
/* Set the download flag */
g_main_loop_quit (data->main_loop);
}
-/* This function is called when playbin2 has created the appsrc element, so we have
+/* This function is called when playbin has created the appsrc element, so we have
* a chance to configure it. */
static void source_setup (GstElement *pipeline, GstElement *source, CustomData *data) {
gchar *audio_caps_text;
/* Initialize GStreamer */
gst_init (&argc, &argv);
- /* Create the playbin2 element */
- data.pipeline = gst_parse_launch ("playbin2 uri=appsrc://", NULL);
+ /* Create the playbin element */
+ data.pipeline = gst_parse_launch ("playbin uri=appsrc://", NULL);
g_signal_connect (data.pipeline, "source-setup", G_CALLBACK (source_setup), &data);
/* Instruct the bus to emit signals for each received message, and connect to the interesting signals */
g_main_loop_quit (data->main_loop);
}
-/* This function is called when playbin2 has created the appsrc element, so we have
+/* This function is called when playbin has created the appsrc element, so we have
* a chance to configure it. */
static void source_setup (GstElement *pipeline, GstElement *source, CustomData *data) {
gchar *audio_caps_text;
/* Initialize GStreamer */
gst_init (&argc, &argv);
- /* Create the playbin2 element */
- data.pipeline = gst_parse_launch ("playbin2 uri=appsrc://", NULL);
+ /* Create the playbin element */
+ data.pipeline = gst_parse_launch ("playbin uri=appsrc://", NULL);
g_signal_connect (data.pipeline, "source-setup", G_CALLBACK (source_setup), &data);
/* Instruct the bus to emit signals for each received message, and connect to the interesting signals */
" 'Q' to quit\n");
/* Build the pipeline */
- data.pipeline = gst_parse_launch ("playbin2 uri=http://docs.gstreamer.com/media/sintel_trailer-480p.webm", NULL);
+ data.pipeline = gst_parse_launch ("playbin uri=http://docs.gstreamer.com/media/sintel_trailer-480p.webm", NULL);
/* Add a keyboard watch so we get notified of keystrokes */
#ifdef _WIN32
#include <gst/gst.h>
-/* playbin2 flags */
+/* playbin flags */
typedef enum {
GST_PLAY_FLAG_VIS = (1 << 3) /* Enable rendering of visualizations when there is no video stream. */
} GstPlayFlags;
return -1;
/* Build the pipeline */
- pipeline = gst_parse_launch ("playbin2 uri=http://radio.hbr1.com:19800/ambient.ogg", NULL);
+ pipeline = gst_parse_launch ("playbin uri=http://radio.hbr1.com:19800/ambient.ogg", NULL);
/* Set the visualization flag */
g_object_get (pipeline, "flags", &flags, NULL);
flags |= GST_PLAY_FLAG_VIS;
g_object_set (pipeline, "flags", flags, NULL);
- /* set vis plugin for playbin2 */
+ /* set vis plugin for playbin */
g_object_set (pipeline, "vis-plugin", vis_plugin, NULL);
/* Start playing */
gst_init (&argc, &argv);\r
\r
/* Build the pipeline */\r
- pipeline = gst_parse_launch ("playbin2 uri=http://docs.gstreamer.com/media/sintel_trailer-480p.webm", NULL);\r
+ pipeline = gst_parse_launch ("playbin uri=http://docs.gstreamer.com/media/sintel_trailer-480p.webm", NULL);\r
\r
/* Create the elements inside the sink bin */\r
equalizer = gst_element_factory_make ("equalizer-3bands", "equalizer");\r
g_object_set (G_OBJECT (equalizer), "band1", (gdouble)-24.0, NULL);\r
g_object_set (G_OBJECT (equalizer), "band2", (gdouble)-24.0, NULL);\r
\r
- /* Set playbin2's audio sink to be our sink bin */\r
+ /* Set playbin's audio sink to be our sink bin */\r
g_object_set (GST_OBJECT (pipeline), "audio-sink", bin, NULL);\r
\r
/* Start playing */\r
" 'Q' to quit\n");
/* Build the pipeline */
-// data.pipeline = gst_parse_launch ("playbin2 uri=http://docs.gstreamer.com/media/sintel_trailer-480p.webm", NULL);
- data.pipeline = gst_parse_launch ("playbin2 uri=file:///f:/media/sintel/sintel_trailer-480p.webm", NULL);
+// data.pipeline = gst_parse_launch ("playbin uri=http://docs.gstreamer.com/media/sintel_trailer-480p.webm", NULL);
+ data.pipeline = gst_parse_launch ("playbin uri=file:///f:/media/sintel/sintel_trailer-480p.webm", NULL);
/* Add a keyboard watch so we get notified of keystrokes */
#ifdef _WIN32
ffmpegcolorspace \! overlay.video\_sink filesrc location=movie.srt \!
subparse \! overlay.text\_sink**
-Play an AVI movie with an external text subtitle stream using playbin2
+Play an AVI movie with an external text subtitle stream using playbin
-**gst-launch-1.0 playbin2 uri=<file:///path/to/movie.avi>
+**gst-launch-1.0 playbin uri=<file:///path/to/movie.avi>
suburi=<file:///path/to/movie.srt>**
**Network streaming**
It also uses the knowledge gathered in the [Basic
tutorials](Basic%2Btutorials.html) regarding:
- - How to use `playbin2` to play any kind of media
+ - How to use `playbin` to play any kind of media
- How to handle network resilience problems
# Introduction
From the previous tutorials, we already have almost all necessary pieces
to build a media player. The most complex part is assembling a pipeline
which retrieves, decodes and displays the media, but we already know
-that the `playbin2` element can take care of all that for us. We only
+that the `playbin` element can take care of all that for us. We only
need to replace the manual pipeline we used in [iOS tutorial 3:
Video](iOS%2Btutorial%2B3%253A%2BVideo.html) with a
-single-element `playbin2` pipeline and we are good to go\!
+single-element `playbin` pipeline and we are good to go\!
However, we can do better than. We will add a [Time
Slider](http://developer.apple.com/library/ios/#documentation/UIKit/Reference/UISlider_Class/Reference/Reference.html),
Supporting arbitrary media URIs
The `GStreamerBackend` provides the `setUri()` method so we can
-indicate the URI of the media to play. Since `playbin2` will be taking
+indicate the URI of the media to play. Since `playbin` will be taking
care of retrieving the media, we can use local or remote URIs
indistinctly (`file://` or `http://`, for example). From the UI code,
though, we want to keep track of whether the file is local or remote,
g_main_context_push_thread_default(context);
/* Build pipeline */
- pipeline = gst_parse_launch("playbin2", &error);
+ pipeline = gst_parse_launch("playbin", &error);
if (error) {
gchar *message = g_strdup_printf("Unable to build pipeline: %s", error->message);
g_clear_error (&error);
We first need to obtain a plain `char *` from within the `NSString *` we
get, using the `UTF8String` method.
-`playbin2`’s URI is exposed as a common GObject property, so we simply
+`playbin`’s URI is exposed as a common GObject property, so we simply
set it with `g_object_set()`.
### Reporting media size
```
We first retrieve the video sink element from the pipeline, using
-the `video-sink` property of `playbin2`, and then its sink Pad. The
+the `video-sink` property of `playbin`, and then its sink Pad. The
negotiated Caps of this Pad, which we recover using
`gst_pad_get_negotiated_caps()`, are the Caps of the decoded media.
### Conclusion
-This tutorial has shown how to embed a `playbin2` pipeline into an iOS
+This tutorial has shown how to embed a `playbin` pipeline into an iOS
application. This, effectively, turns such application into a basic
media player, capable of streaming and decoding all the formats
GStreamer understands. More particularly, it has shown:
Basic+tutorial+15+Clutter+integration.markdown
Basic+tutorial+16+Platform-specific+elements.markdown
Playback+tutorials.markdown
- Playback+tutorial+1+Playbin2+usage.markdown
+ Playback+tutorial+1+Playbin+usage.markdown
Playback+tutorial+2+Subtitle+management.markdown
Playback+tutorial+3+Short-cutting+the+pipeline.markdown
Playback+tutorial+4+Progressive+streaming.markdown
Playback+tutorial+5+Color+Balance.markdown
Playback+tutorial+6+Audio+visualization.markdown
- Playback+tutorial+7+Custom+playbin2+sinks.markdown
+ Playback+tutorial+7+Custom+playbin+sinks.markdown
Playback+tutorial+8+Hardware-accelerated+video+decoding.markdown
Playback+tutorial+9+Digital+audio+pass-through.markdown
Android+tutorials.markdown
projects / platform / upstream / gstreamer.git / commitdiff