Class MediaStream

All Implemented Interfaces:
PointerInterface
Direct Known Subclasses:
MediaFile

public class MediaStream extends Object
`GtkMediaStream` is the integration point for media playback inside GTK.

GTK provides an implementation of the `GtkMediaStream` interface that
is called [class@Gtk.MediaFile].

Apart from application-facing API for stream playback, `GtkMediaStream`
has a number of APIs that are only useful for implementations and should
not be used in applications:
[method@Gtk.MediaStream.prepared],
[method@Gtk.MediaStream.unprepared],
[method@Gtk.MediaStream.update],
[method@Gtk.MediaStream.ended],
[method@Gtk.MediaStream.seek_success],
[method@Gtk.MediaStream.seek_failed],
[method@Gtk.MediaStream.gerror],
[method@Gtk.MediaStream.error],
[method@Gtk.MediaStream.error_valist].

https://docs.gtk.org/gtk4/class.MediaStream.html

  • Constructor Details

  • Method Details

    • getClassHandler

      public static ClassHandler getClassHandler()
    • error

      public void error(int domain, int code, @Nonnull Str format, Object... _elipse)
      Sets @self into an error state using a printf()-style format string.

      This is a utility function that calls [method@Gtk.MediaStream.gerror].
      See that function for details.
      Parameters:
      domain - error domain
      code - error code
      format - printf()-style format for error message
      _elipse - parameters for message format
    • error

      public void error(int domain, int code, String format, Object... _elipse)
      Sets @self into an error state using a printf()-style format string.

      This is a utility function that calls [method@Gtk.MediaStream.gerror].
      See that function for details.
      Parameters:
      domain - error domain
      code - error code
      format - printf()-style format for error message
      _elipse - parameters for message format
    • gerror

      public void gerror(@Nonnull Error error)
      Sets @self into an error state.

      This will pause the stream (you can check for an error
      via [method@Gtk.MediaStream.get_error] in your
      GtkMediaStream.pause() implementation), abort pending
      seeks and mark the stream as prepared.

      if the stream is already in an error state, this call
      will be ignored and the existing error will be retained.

      To unset an error, the stream must be reset via a call to
      [method@Gtk.MediaStream.unprepared].
      Parameters:
      error - the `GError` to set
    • getDuration

      public long getDuration()
      Gets the duration of the stream.

      If the duration is not known, 0 will be returned.
      Returns:
      the duration of the stream or 0 if not known.
    • getEnded

      public boolean getEnded()
      Returns whether the streams playback is finished.
      Returns:
      %TRUE if playback is finished
    • getError

      public Error getError()
      If the stream is in an error state, returns the `GError`
      explaining that state.

      Any type of error can be reported here depending on the
      implementation of the media stream.

      A media stream in an error cannot be operated on, calls
      like [method@Gtk.MediaStream.play] or
      [method@Gtk.MediaStream.seek] will not have any effect.

      `GtkMediaStream` itself does not provide a way to unset
      an error, but implementations may provide options. For example,
      a [class@Gtk.MediaFile] will unset errors when a new source is
      set, e.g. with [method@Gtk.MediaFile.set_file].
      Returns:
      %NULL if not in an error state or the `GError` of the stream
    • getLoop

      public boolean getLoop()
      Returns whether the stream is set to loop.

      See [method@Gtk.MediaStream.set_loop] for details.
      Returns:
      %TRUE if the stream should loop
    • getMuted

      public boolean getMuted()
      Returns whether the audio for the stream is muted.

      See [method@Gtk.MediaStream.set_muted] for details.
      Returns:
      %TRUE if the stream is muted
    • getPlaying

      public boolean getPlaying()
      Return whether the stream is currently playing.
      Returns:
      %TRUE if the stream is playing
    • getTimestamp

      public long getTimestamp()
      Returns the current presentation timestamp in microseconds.
      Returns:
      the timestamp in microseconds
    • getVolume

      public double getVolume()
      Returns the volume of the audio for the stream.

      See [method@Gtk.MediaStream.set_volume] for details.
      Returns:
      volume of the stream from 0.0 to 1.0
    • hasAudio

      public boolean hasAudio()
      Returns whether the stream has audio.
      Returns:
      %TRUE if the stream has audio
    • hasVideo

      public boolean hasVideo()
      Returns whether the stream has video.
      Returns:
      %TRUE if the stream has video
    • isPrepared

      public boolean isPrepared()
      Returns whether the stream has finished initializing.

      At this point the existence of audio and video is known.
      Returns:
      %TRUE if the stream is prepared
    • isSeekable

      public boolean isSeekable()
      Checks if a stream may be seekable.

      This is meant to be a hint. Streams may not allow seeking even if
      this function returns %TRUE. However, if this function returns
      %FALSE, streams are guaranteed to not be seekable and user interfaces
      may hide controls that allow seeking.

      It is allowed to call [method@Gtk.MediaStream.seek] on a non-seekable
      stream, though it will not do anything.
      Returns:
      %TRUE if the stream may support seeking
    • isSeeking

      public boolean isSeeking()
      Checks if there is currently a seek operation going on.
      Returns:
      %TRUE if a seek operation is ongoing.
    • pause

      public void pause()
      Pauses playback of the stream.

      If the stream is not playing, do nothing.
    • play

      public void play()
      Starts playing the stream.

      If the stream is in error or already playing, do nothing.
    • realize

      public void realize(@Nonnull Surface surface)
      Called by users to attach the media stream to a `GdkSurface` they manage.

      The stream can then access the resources of @surface for its
      rendering purposes. In particular, media streams might want to
      create a `GdkGLContext` or sync to the `GdkFrameClock`.

      Whoever calls this function is responsible for calling
      [method@Gtk.MediaStream.unrealize] before either the stream
      or @surface get destroyed.

      Multiple calls to this function may happen from different
      users of the video, even with the same @surface. Each of these
      calls must be followed by its own call to
      [method@Gtk.MediaStream.unrealize].

      It is not required to call this function to make a media stream work.
      Parameters:
      surface - a `GdkSurface`
    • seek

      public void seek(long timestamp)
      Start a seek operation on @self to @timestamp.

      If @timestamp is out of range, it will be clamped.

      Seek operations may not finish instantly. While a
      seek operation is in process, the [property@Gtk.MediaStream:seeking]
      property will be set.

      When calling gtk_media_stream_seek() during an
      ongoing seek operation, the new seek will override
      any pending seek.
      Parameters:
      timestamp - timestamp to seek to.
    • seekFailed

      public void seekFailed()
      Ends a seek operation started via GtkMediaStream.seek() as a failure.

      This will not cause an error on the stream and will assume that
      playback continues as if no seek had happened.

      See [method@Gtk.MediaStream.seek_success] for the other way of
      ending a seek.
    • seekSuccess

      public void seekSuccess()
      Ends a seek operation started via GtkMediaStream.seek() successfully.

      This function will unset the GtkMediaStream:ended property
      if it was set.

      See [method@Gtk.MediaStream.seek_failed] for the other way of
      ending a seek.
    • setLoop

      public void setLoop(boolean loop)
      Sets whether the stream should loop.

      In this case, it will attempt to restart playback
      from the beginning instead of stopping at the end.

      Not all streams may support looping, in particular
      non-seekable streams. Those streams will ignore the
      loop setting and just end.
      Parameters:
      loop - %TRUE if the stream should loop
    • setMuted

      public void setMuted(boolean muted)
      Sets whether the audio stream should be muted.

      Muting a stream will cause no audio to be played, but it
      does not modify the volume. This means that muting and
      then unmuting the stream will restore the volume settings.

      If the stream has no audio, calling this function will
      still work but it will not have an audible effect.
      Parameters:
      muted - %TRUE if the stream should be muted
    • setPlaying

      public void setPlaying(boolean playing)
      Starts or pauses playback of the stream.
      Parameters:
      playing - whether to start or pause playback
    • setVolume

      public void setVolume(double volume)
      Sets the volume of the audio stream.

      This function call will work even if the stream is muted.

      The given @volume should range from 0.0 for silence to 1.0
      for as loud as possible. Values outside of this range will
      be clamped to the nearest value.

      If the stream has no audio or is muted, calling this function
      will still work but it will not have an immediate audible effect.
      When the stream is unmuted, the new volume setting will take effect.
      Parameters:
      volume - New volume of the stream from 0.0 to 1.0
    • streamEnded

      public void streamEnded()
      Pauses the media stream and marks it as ended.

      This is a hint only, calls to [method@Gtk.MediaStream.play]
      may still happen.

      The media stream must be prepared when this function is called.
    • streamPrepared

      public void streamPrepared(boolean has_audio, boolean has_video, boolean seekable, long duration)
      Called by `GtkMediaStream` implementations to advertise the stream
      being ready to play and providing details about the stream.

      Note that the arguments are hints. If the stream implementation
      cannot determine the correct values, it is better to err on the
      side of caution and return %TRUE. User interfaces will use those
      values to determine what controls to show.

      This function may not be called again until the stream has been
      reset via [method@Gtk.MediaStream.stream_unprepared].
      Parameters:
      has_audio - %TRUE if the stream should advertise audio support
      has_video - %TRUE if the stream should advertise video support
      seekable - %TRUE if the stream should advertise seekability
      duration - The duration of the stream or 0 if unknown
    • streamUnprepared

      public void streamUnprepared()
      Resets a given media stream implementation.

      [method@Gtk.MediaStream.stream_prepared] can then be called again.

      This function will also reset any error state the stream was in.
    • unrealize

      public void unrealize(@Nonnull Surface surface)
      Undoes a previous call to gtk_media_stream_realize().

      This causes the stream to release all resources it had
      allocated from @surface.
      Parameters:
      surface - the `GdkSurface` the stream was realized with
    • update

      public void update(long timestamp)
      Media stream implementations should regularly call this
      function to update the timestamp reported by the stream.

      It is up to implementations to call this at the frequency
      they deem appropriate.

      The media stream must be prepared when this function is called.
      Parameters:
      timestamp - the new timestamp
    • asPaintable

      public Paintable asPaintable()
      Implements interface Paintable. Call this to get access to interface functions.
      Returns:
      Paintable
    • getTypeID

      public static long getTypeID()
    • getParentTypeID

      public static long getParentTypeID()
    • getTypeSize

      public static TypeSystem.TypeSize getTypeSize()
    • getParentTypeSize

      public static TypeSystem.TypeSize getParentTypeSize()
    • getInstanceSize

      public static int getInstanceSize()