[mythtv-users] Uncool surprise... coming back from vacation, shows not recorded.

[f-myth-users at media.mit.edu]

    Date: Mon, 5 Dec 2005 15:22:22 +0100
    From: Chris Rouch <chris.rouch at gmail.com>

    > P.S.  Is there an easy tool of producing a series of thumbnails of
    > every scene change from a section of video?  (Or perhaps just a single
    > frame from every n minutes, regardless of scenes.)  That would be
    > handy no matter what, to quickly notice that the middle of something
    > got trashed, or to make it possible to notice that, e.g., PBS decided
    > to show an hour of Exciting Legislators Voting and Debating instead of
    > whatever they originally scheduled, which also happens quite a bit
    > here... :)  The idea is to have something so low-bandwidth that it
    > could be quickly checked at the other end of some network link far
    > from home, allowing manual rescheduling via mythweb...
    >

    You can use mplayer for this. I needed to play around with the -ss and
    -frames options, and to generate more images than I needed to get a
    reliable number of images per minute, but basically all you need is:

    mplayer -vo png -ss N

    You can use '-identify' to find out how long the recording is and then
    iterate through it.

Thanks!  That might be a reasonable stopgap; it'd be ideal if I could
just pull out scene-change frames (which mpeg must make reasonable easy),
but I can try this until I get that working...