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Re: .uvc WebCam Data

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Martin McCormick wrote:

> Thank you very much.  I started using unix-like OS's 30
> years ago in June but the digital video field is new to me so I
> still have a lot of learning to do.
> 
> As an electronics and amateur radio enthusiast, I am
> astounded at how fast that A/D converter has to work along with
> the Nyquist filtering to properly digitize the video.
> 
> With North American NTSC color video, the dot clock rate
> is 3.7945 million plus a few more decimal places per second and
> PAL along with SECAM are just above 4 MHZ.  The A/D converter has
> to sample at twice that rate to keep Mr. Nyquist from haunting
> anybody from his grave.

I still don't get it how you want to capture and process video to text to
audio - perhaps deduplicate frame content etc. - how many frames per second
do you want to process, cause I did not get this with the 4Mhz and how it
is relevant. I was thinking your display is running at 60Hz, which is most
common nowdays. This means you have 60 images/sec .... hmmm how do you
process 60/sec?
I am really wondering.

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Thread

.uvc WebCam Data "Martin McCormick" <martin.m@suddenlink.net> - 2019-08-08 19:10 +0200
  Re: .uvc WebCam Data Dan Ritter <dsr@randomstring.org> - 2019-08-08 21:20 +0200
    Re: .uvc WebCam Data "Martin McCormick" <martin.m@suddenlink.net> - 2019-08-08 22:30 +0200
      Re: .uvc WebCam Data deloptes <deloptes@gmail.com> - 2019-08-09 00:10 +0200
        Re: .uvc WebCam Data Dan Ritter <dsr@randomstring.org> - 2019-08-09 02:30 +0200
          Re: .uvc WebCam Data "Martin McCormick" <martin.m@suddenlink.net> - 2019-08-09 14:40 +0200
        Re: .uvc WebCam Data "Martin McCormick" <martin.m@suddenlink.net> - 2019-08-09 05:10 +0200
    Re: .uvc WebCam Data "Martin McCormick" <martin.m@suddenlink.net> - 2019-08-12 19:20 +0200
      Re: .uvc WebCam Data Dan Ritter <dsr@randomstring.org> - 2019-08-12 20:30 +0200

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