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Thursday, 28 September, 2006

I’m screwing with the webcam again. Here’s what I’ve learned so far.

  • Oddly, the USB ports on the back of my motherboard are USB 1.1 only. I have four additional USB 2.2 ports which attach to a unit which is intended to stick out of the back of the machine. The unit which facilitates this is lost and proprietary.
  • Any resolution including 320×240 or below sends the same data stream into the system.
  • The audio stream goes through this same port, as the only microphone I have is integral to the camera. This slows things down considerably.
  • Any frame rate including and below 12 FPS appears to send the same data into the system.
  • With the setup I have I cannot parse the image down below 24 bits-per-pixel. Anyway, this is done in software and would slow the system even more.
  • In order to make a video all I have to type on the command line is:

    mencoder tv:// -tv driver=v4l:width=320:height=240:device=/dev/video0:forceaudio:audiorate=12000:adevice=/dev/dsp2 -ovc raw -oac pcm -ofps 12 -o /media/hdd1/[name of video].mpeg

    I have a new appreciation for the GUI.

  • I have yet to do the analysis comparing pricing a build-your-own system sourced from Newegg or some such place, and a red-tag Mac with the appropriate external storage. On the other hand, I’ve got to send Otis to the Doc one of these days and other forces continue to encourage me to economize. The up-to-date box will have to wait. Of course, I could just get a new board and chip. Anything would be an improvement over ye olde Duron.
  • The disk uptake on the old Macintosh is such that the video result is even worse even though QuickTime Pro would be nice to use if only I could get a good video on the system in the first place.
  • The videos I create are profoundly huge. Around 10MB per second. Then I process and compress them down into something reasonable. I just push the VCD button and the videos automagically reformat to 30fps, 352×240, etc. The result is around 1.5 MB per minute. This process is dramatically faster than it was on a Windows system.

I don’t know what to practically do, although I may carry on frame rate be damned.


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