Why MediaMetaDataRetriever is taking so much time to retrieve Album Art?

Question

I have a function from which I retrieve Album Art of all audio files. The problem is, though that it takes atleast a minute to retrieve the album art of 100-200 audio files. How can I make it take less time for retrieving album art??

private Bitmap getAlbumImage(String path) {
        android.media.MediaMetadataRetriever mmr = new MediaMetadataRetriever();
        mmr.setDataSource(path);
        byte[] data = mmr.getEmbeddedPicture();
        if (data != null) return BitmapFactory.decodeByteArray(data, 0, data.length);
        return null;
    }