--- title: Retrieving metadata --- ## During playback ## The metadata of the media can be retrieved during playback in multiple ways. The most straightforward is to listen for the `Player.Listener#onMediaMetadataChanged` event; this will provide a [`MediaMetadata`][] object for use, which has fields such as `title` and `albumArtist`. Alternatively, calling `Player#getMediaMetadata` returns the same object. ~~~ public void onMediaMetadataChanged(MediaMetadata mediaMetadata) { if (mediaMetadata.title != null) { handleTitle(mediaMetadata.title); } } ~~~ {: .language-java} If an application needs access to specific [`Metadata.Entry`][] objects, then it should add a `MetadataOutput` (for dynamic metadata delivered during playback) to the player. Alternatively, if there is a need to look at static metadata, this can be accessed through the `TrackSelections#getFormat`. Both of these options are used to populate the `Player#getMediaMetadata`. ## Without playback ## If playback is not needed, it is more efficient to use the [`MetadataRetriever`][] to extract the metadata because it avoids having to create and prepare a player. ~~~ ListenableFuture trackGroupsFuture = MetadataRetriever.retrieveMetadata(context, mediaItem); Futures.addCallback( trackGroupsFuture, new FutureCallback() { @Override public void onSuccess(TrackGroupArray trackGroups) { handleMetadata(trackGroups); } @Override public void onFailure(Throwable t) { handleFailure(t); } }, executor); ~~~ {: .language-java} ## Motion photos ## It is also possible to extract the metadata of a motion photo, containing the image and video offset and length for example. The supported formats are: * JPEG motion photos recorded by Google Pixel and Samsung camera apps. This format is playable by ExoPlayer and the associated metadata can therefore be retrieved with a player or using the `MetadataRetriever`. * HEIC motion photos recorded by Google Pixel and Samsung camera apps. This format is currently not playable by ExoPlayer and the associated metadata should therefore be retrieved using the `MetadataRetriever`. For motion photos, the `TrackGroupArray` obtained with the `MetadataRetriever` contains a `TrackGroup` with a single `Format` enclosing a [`MotionPhotoMetadata`][] metadata entry. ~~~ for (int i = 0; i < trackGroups.length; i++) { TrackGroup trackGroup = trackGroups.get(i); Metadata metadata = trackGroup.getFormat(0).metadata; if (metadata != null && metadata.length() == 1) { Metadata.Entry metadataEntry = metadata.get(0); if (metadataEntry instanceof MotionPhotoMetadata) { MotionPhotoMetadata motionPhotoMetadata = (MotionPhotoMetadata) metadataEntry; handleMotionPhotoMetadata(motionPhotoMetadata); } } } ~~~ {: .language-java} [`MediaMetadata`]: {{ site.exo_sdk }}/MediaMetadata.html [`Metadata.Entry`]: {{ site.exo_sdk }}/metadata/Metadata.Entry.html [`MetadataRetriever`]: {{ site.exo_sdk }}/MetadataRetriever.html [`MotionPhotoMetadata`]: {{ site.exo_sdk }}/metadata/mp4/MotionPhotoMetadata.html