Hi zentara
thanks for your reply!
I think that might do the trick, but I don't think that that is a solution for me... this is a PC that will run as an embedded system with no keyboard or mouse (that's why I need that paralell port button I've mentioned).
I've tried before with ffmpeg (that I think is the base that mplayer uses) and the results were not that good...
Thanks again for answering! I'll just keep looking!!

Has anyone been able to set a callback from a pad in GStreamer? I think that through that I might be able to take my picture, but I found absolutely no documentation for Perl :-(
in c this is made through
 gst_pad_add_probe(GstPad *pad,GstPadProbeType mask,GstPadProbeCallback callback,gpointer user_data,GDestroyNotify destroy_data);
But i did't found the Perl equivalent...