When is it possible to use the mark()-method on a stream, i.e. how do I have to define (new?) a stream to be able to set a mark in it? I have a stream that I want to scroll back in (it is a movie with frames). It would be great if you could go back to the previous frame(picture) in the stream by having set the mark at the beginning and, reset() to the mark and skip to the correct oofset (i.e. the previous picture).