Interface LoadControl

  • All Known Implementing Classes:
    DefaultLoadControl

    public interface LoadControl
    Controls buffering of media.
    • Method Summary

      All Methods Instance Methods Abstract Methods 
      Modifier and Type Method Description
      Allocator getAllocator()
      Returns the Allocator that should be used to obtain media buffer allocations.
      long getBackBufferDurationUs()
      Returns the duration of media to retain in the buffer prior to the current playback position, for fast backward seeking.
      void onPrepared()
      Called by the player when prepared with a new source.
      void onReleased()
      Called by the player when released.
      void onStopped()
      Called by the player when stopped.
      void onTracksSelected​(Renderer[] renderers, TrackGroupArray trackGroups, ExoTrackSelection[] trackSelections)
      Called by the player when a track selection occurs.
      boolean retainBackBufferFromKeyframe()
      Returns whether media should be retained from the keyframe before the current playback position minus getBackBufferDurationUs(), rather than any sample before or at that position.
      boolean shouldContinueLoading​(long playbackPositionUs, long bufferedDurationUs, float playbackSpeed)
      Called by the player to determine whether it should continue to load the source.
      boolean shouldStartPlayback​(long bufferedDurationUs, float playbackSpeed, boolean rebuffering, long targetLiveOffsetUs)
      Called repeatedly by the player when it's loading the source, has yet to start playback, and has the minimum amount of data necessary for playback to be started.
    • Method Detail

      • onPrepared

        void onPrepared()
        Called by the player when prepared with a new source.
      • onTracksSelected

        void onTracksSelected​(Renderer[] renderers,
                              TrackGroupArray trackGroups,
                              ExoTrackSelection[] trackSelections)
        Called by the player when a track selection occurs.
        Parameters:
        renderers - The renderers.
        trackGroups - The TrackGroups from which the selection was made.
        trackSelections - The track selections that were made.
      • onStopped

        void onStopped()
        Called by the player when stopped.
      • onReleased

        void onReleased()
        Called by the player when released.
      • getAllocator

        Allocator getAllocator()
        Returns the Allocator that should be used to obtain media buffer allocations.
      • getBackBufferDurationUs

        long getBackBufferDurationUs()
        Returns the duration of media to retain in the buffer prior to the current playback position, for fast backward seeking.

        Note: If retainBackBufferFromKeyframe() is false then seeking in the back-buffer will only be fast if the back-buffer contains a keyframe prior to the seek position.

        Note: Implementations should return a single value. Dynamic changes to the back-buffer are not currently supported.

        Returns:
        The duration of media to retain in the buffer prior to the current playback position, in microseconds.
      • retainBackBufferFromKeyframe

        boolean retainBackBufferFromKeyframe()
        Returns whether media should be retained from the keyframe before the current playback position minus getBackBufferDurationUs(), rather than any sample before or at that position.

        Warning: Returning true will cause the back-buffer size to depend on the spacing of keyframes in the media being played. Returning true is not recommended unless you control the media and are comfortable with the back-buffer size exceeding getBackBufferDurationUs() by as much as the maximum duration between adjacent keyframes in the media.

        Note: Implementations should return a single value. Dynamic changes to the back-buffer are not currently supported.

        Returns:
        Whether media should be retained from the keyframe before the current playback position minus getBackBufferDurationUs(), rather than any sample before or at that position.
      • shouldContinueLoading

        boolean shouldContinueLoading​(long playbackPositionUs,
                                      long bufferedDurationUs,
                                      float playbackSpeed)
        Called by the player to determine whether it should continue to load the source.
        Parameters:
        playbackPositionUs - The current playback position in microseconds, relative to the start of the period that will continue to be loaded if this method returns true. If playback of this period has not yet started, the value will be negative and equal in magnitude to the duration of any media in previous periods still to be played.
        bufferedDurationUs - The duration of media that's currently buffered.
        playbackSpeed - The current factor by which playback is sped up.
        Returns:
        Whether the loading should continue.
      • shouldStartPlayback

        boolean shouldStartPlayback​(long bufferedDurationUs,
                                    float playbackSpeed,
                                    boolean rebuffering,
                                    long targetLiveOffsetUs)
        Called repeatedly by the player when it's loading the source, has yet to start playback, and has the minimum amount of data necessary for playback to be started. The value returned determines whether playback is actually started. The load control may opt to return false until some condition has been met (e.g. a certain amount of media is buffered).
        Parameters:
        bufferedDurationUs - The duration of media that's currently buffered.
        playbackSpeed - The current factor by which playback is sped up.
        rebuffering - Whether the player is rebuffering. A rebuffer is defined to be caused by buffer depletion rather than a user action. Hence this parameter is false during initial buffering and when buffering as a result of a seek operation.
        targetLiveOffsetUs - The desired playback position offset to the live edge in microseconds, or C.TIME_UNSET if the media is not a live stream or no offset is configured.
        Returns:
        Whether playback should be allowed to start or resume.