.........
new FrameThread(item.get("arg0") ).execute(imageView);
.......

public class FrameThread extends AsyncTask<Object, Void, Bitmap>
..................................
	@Override
	protected Bitmap doInBackground(Object... params) {
                imageView = (ImageView) params[0];
                mmr = new FFmpegMediaMetadataRetriever();
                mmr.setDataSource(filePath);
                Bitmap b = mmr.getFrameAtTime(2000000,  FFmpegMediaMetadataRetriever.OPTION_CLOSEST); 				
                return b;
	}

	@Override
    protected void onPostExecute(Bitmap result) {
               imageView.setImageBitmap(result);
    }