actually some fan sub has done it in removing the recorded video display which they recorded from their sat receiver. its much more easier to remove sub than to remove mosaic. the easiest answer is no. cause you have no data of the actual pixel area. all are smuged. but some ppl claim if you're really pro in Mathlab, then there is a way. but don't expect 100% restoration. it will be around 60-70%. you have to be a pro to get such results. and everything is done frame by frame.