Zend certified PHP/Magento developer

How to capture video with capture card and process in Python or Matlab?

I have an HDMI to USB3.0+HDMI Capture card. My device is streaming into the HDMI-in, where it is then connected to the laptop. How do I go about retrieving this video, then processing it in Python, and then displaying it?

I am using a Mac, if that helps.

Thank you!