/// <summary>
/// Exports the audio of a media item to storage.
/// </summary>
/// <returns><c>true</c> if audio started exporting, <c>false</c> if it is exporting another audio or the media item has DRM.</returns>
/// <param name="mediaItem">Media item.</param>
/// <param name="outputFolder">Absolute output folder or specify null to use Documents folder.</param>
/// <param name="outputFile">Output file name or specify null to use <c>[artist] - [title].[extension]</c>.</param>
/// <param name="overwrite">Whether to overwrite the output file.</param>
public static bool ExportAudio(MPMediaItem mediaItem, string outputFolder = null, string outputFile = null, bool overwrite = false)
{
if (_exporter != null)
{
return(false);
}
if (mediaItem == null)
{
return(false);
}
if (outputFolder == null)
{
outputFolder = Application.persistentDataPath;
}
NSURL assetURL = mediaItem.Value(MPMediaItem.PropertyAssetURL) as NSURL;
if (assetURL == null)
{
return(false);
}
if (outputFile == null)
{
string artist = mediaItem.Value(MPMediaItem.PropertyArtist) as string;
string title = mediaItem.Value(MPMediaItem.PropertyTitle) as string;
string extension = Path.GetExtension(assetURL.AbsoluteString().Split('?')[0]);
outputFile = artist + " - " + title + extension;
}
_outputPath = outputFolder + "/" + outputFile;
if (!overwrite && File.Exists(_outputPath))
{
return(false);
}
_avAsset = AVURLAsset.Asset(assetURL);
_exporter = new AVAssetExportSession(_avAsset, AVAssetExportSession.AVAssetExportPresetPassthrough);
_exporter.outputFileType = "com.apple.quicktime-movie";
_exporter.shouldOptimizeForNetworkUse = true;
string tmpExt = UTType.CopyPreferredTag(_exporter.outputFileType, UTType.kUTTagClassFilenameExtension);
_tmpPath = Application.persistentDataPath + "/" + UUID.Generate() + "." + tmpExt;
_exporter.outputURL = new NSURL(_tmpPath, false);
_exporter.ExportAsynchronously(_OnExportDone);
return(true);
}
private static void _OnWriteCompletion(NSURL assetURL, NSError error)
{
if (error == null)
{
if (_exportCompletedHandlers != null)
{
_exportCompletedHandlers(null, new PhotosLibraryExportedEventArgs(assetURL.AbsoluteString()));
}
}
else
{
if (_exportFailedHandlers != null)
{
_exportFailedHandlers(null, new U3DXTErrorEventArgs(error));
}
}
}
private static void _OnWriteCompletion(NSURL assetURL, NSError error)
{
if (error == null) {
if (_exportCompletedHandlers != null)
_exportCompletedHandlers(null, new PhotosLibraryExportedEventArgs(assetURL.AbsoluteString()));
} else {
if (_exportFailedHandlers != null)
_exportFailedHandlers(null, new U3DXTErrorEventArgs(error));
}
}
