Capturing Raw USB Video Data Using Linux Command Line

I am fed up with video capturing software I have to buy, especially on windows. Never really works.
I want to capture skype lessons I have so I want to do it as elegant and minimalistic as possible on Linux.

Here is what I propose.
Since my monitor is on USB and runs skype full screen,

  1. I want to e.g. do a cat /dev/“usbmonitor” >/file
  2. Then if available use a program that will replay the USB packets and create an mpg or some usable format video file.
  3. I would REALLY appreciate command line solution. Gui makes clickery and unnecessary mess.

Any ideas or counter command line options that could work ?

I tried G-streamer and guvc, but it is not working with USB monitors.

Thanks

What’s the monitor name model?

Viewsonic VX2450WM-LED
There is nothing wrong with the monitor it works perfectly. All I want is to capture the video stream by command line.
The Monitor is connected via USB through a USB to DVI converter.

It is trivial to capture the USB packets to the monitor.
Is there a program that will convert the packets to an mpeg ?