IBM PowerPC ThinkPad - Video Capture

1998-09-08 I'm interested in hearing about experiences with the ThinkPad 850's (and 860's?) video capture adapter (VCA).  That's the little video-in jack on the back that comes standard with all 850's (and 860's?) that lets you "record" video signals from a source like a VCR.  This is not to be confused with the optional clip-on camera that utilizes this adapter.

I finally got UMS to record some video from a VCR signal but I noticed I get very poor frame rates.  It seems like 3-5 fps continuous for long (>30 sec) clips is the max the little computer and its SCSI drive can handle (with 22khz mono audio).  Saving the result as AVI turns out ok, albeit a little jerky.  But why does UMS give the option of 30 fps when the VCA can't possible keep up?

To make it more frustrating, the documentation says that to make good MPEGs one must record at a fps of 24 or 30.

I suppose, considering it seems the VCA is using uncompressed raw video direct to disk instead of pre-compressing it in hardware, that 5 fps is pretty good.
Lately I've been having strange problems with the VCA.  Sometimes it switches into a grayscale mode and refuses to allow video_monitor or movie_editor recording in color.  The only way to get it to work again is to uninstall and reinstall the UMS.* filesets and reboot.  Even then it doesn't always work!  That is very frustrating.  My UMS levels are as follows:

  UMS.msg.en_US.objects    C    AIX Ultimedia Services Messages
  UMS.objects          C    AIX Ultimedia Services
  UMS.samples          C    AIX Ultimedia Services Samples
  UMS.video_ext        C    AIX Ultimedia Services Video

Also, movie_editor crashes with an error on the audio device sometimes when I try to record over a minute or so of video/audio.  I don't think it's a file system space problem because I have all the temp files pointed to a large partition which I monitor during recording.

Please share your VCA thoughts with me.  I'm especially interested in hearing about how the 860 performs, as well
as the VCA in the S15 (I think?) adapter on the desktop Power Series machines.

Please e-mail if you have any comments!

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