Recording a movie file to tape from an SGI


Easy version

If you have a movie file (QuickTime, MPEG, AVI, etc) that you want to record onto videotape, there are two possible ways to do so from an SGI - with movieplayer, or with Premiere. If you're making a master tape you should consider using a high quality format like analog or digital beta. If you're just making a copy to show somewhere else, use VHS.

Movieplayer live screendump

  1. Use the high-res patchbay to send the desired computer to the Folsom scan converter. Use the Lyon Lamb zoom controls to zoom as far in as possible, that will be 640x480. (Details on zooming and scrolling the Lyon Lamb are on its page.)

  2. You can start up movieplayer with no borders with the command

    movieplayer -B segment.mov

    (Note that if you're running 4Dwm, the default window manager, you use Alt-F7 to move the window.)

  3. Turn the desktop background black with the command

    xsetroot -solid black

  4. Make sure no other window borders are in the way. Make sure to do this check on a monitor that's in "widescan" mode.

  5. Route the Folsom output to your chosen deck, and record at will.

  6. Pros: pretty straightforward, no need to start up Adobe Premiere.
    Cons: manual positioning of windows onscreen and fiddling with Lyon Lamb zoom/pan controls.

    Premiere print to video

    1. Route moviola's output to your chosen deck. (See below if your destination is a VHS deck.)

    2. Type premiere segment.mov to start up Adobe Premiere. (If it's already started, just use the Open menu.)

    3. The video will come up in a clip window. Pick the File->Export->Print to Video menu item. A dialog box will come up that allows you to set a delay time (number of seconds of black) before the video starts. You probably need at least three seconds so that the beginning of your segment doesn't get cut off (the deck tape heads need time to get up to speed).

    4. Hit "OK" to start. If you're extremely confident, just immediately hit the record button on the deck. It might good to first test that things are set up properly before recording - if the signal appears to be properly routed to the deck (because you've routed the deck to a monitor and you see everything looks fine), then hit 'Esc' to stop the playback. Then just pick Print to Video again to do it for real.

    5. Pros: no futzing with Lyon Lamb controls - exactly the right video stream is produced automatically.
      Cons: those who have never run premiere might be somewhat confused (although you can safely ignore the 99.5% of its functionality which is irrelevant for this task).

    More detail

    Four details about the "print to video approach":

    Square vs. CCIR pixels

    If your movie was made at 640x480 pixels, you should make sure the video control panel is set to use square pixels for output. If your movie was made at 720x486 pixels, you should use CCIR pixels. To set this:
    • Type vcp at the prompt to bring up the video control panel.
    • The Video Output Timing choice at the bottom should be set to either Square NTSC or CCIR NTSC.
    It's probably better to just go with 640x480 pixels, since computer monitors have square pixels. There's a lot of information for the curious about why you might care about square vs non-square pixels at
    Chris Pirazzi's Lurker's Guide to Video page

    VHS Audio

    If you are recording from moviola to a VHS deck, you need to route the audio through the mixer. (You don't have to do this if you're using the
    IO panel to get the signal to a deck that's not part of the usual rack hookup.)

    You can do this through the web interface by being careful about ordering:

    1. Middle-click on moviola then left-click on the deck.
    2. Middle-click on moviola then left-click on the view monitor.
    3. Middle-click on "mixer" then left-click on the deck.
    But in this case copy-pasting the following telect commands may be easier to deal with (this assumes you're using the vhsrec deck):
    telect -lntsc -imoviola -ovhsrec
    telect -laudio -imoviola -omxr12
    telect -laudio -imixer -ovhsrec
    

    Follow the instructions on the audio mixer page to set the sliders properly - your chosen channel (probably mxr12) should be on, all other should be off, make sure to mute the room volume by using the speaker volume button instead of the main LR slider.

    Explanation of sorts: I (Tamara) don't really understand why, but I observed that if you go directly from moviola to a VHS deck you get a good hi-fi signal but a terrible normal signal. So it will sound fine if you play it back in the usual mode on our decks, but people with consumer grade hardware won't hear any sound. Things seem to work fine when the signal is routed through the mixer.

    You can double-check that the normal channels are set properly by either toggling the Audio Out Select button a little to the left of the JVC deck displays until "Normal" no longer appears, or by using the scruffy Panasonic deck in the lower right rack which is an example of a consumer deck that can't playback hi-fi.

    Transcoding

    Remember that if you're using the digital output for any deck except the digital beta, you'll need to go through the FS1 or FS2 transcoder: route moviola to the transcoder, and the transcoder to the deck. Don't forget to make sure the transcoder input select button is set to digital.

    Note that in this case you will have to manually route the audio at the command line, since it's not carried through automatically - some telect command like

    telect -laudio -imoviola -ovhsrec

    You would want to do this when you're routing to something that has component input, like the analog beta deck, in order to get maximum quality. If you're just going directly to VHS, you can use the composite output.

    Colorbars

    Note that although the dialog box allows you to have colorbars in addition to a black screen, I've never gotten that to work (I = Tamara). If you want colorbars, you can do that either as a separate pass before dumping your video, if you've got a nicely blanked tape that's prepared for insert editing. But if you're in a hurry, you can do this all in a single pass with some quick and fancy telect command-line action. An example of the latter, assuming that's you're recording to the digibeta deck and want 30 seconds of colorbars, followed by 10 seconds of black, followed by your video. Of course, if you're recording to a VHS deck, you'll need to invert this by going directly from bars to the deck and using the transcoder to convert moviola digital output to NTSC. Or if it's the analog beta deck you'd convert both to CAV, and so on.

    Additional notes


    Troubleshooting


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    Last modified: Thu Jan 27 20:00:37 PST 2000