You don’t, you wouldn’t even need a webcam, you could just splice into the video...

noir_lord on Feb 13, 2019 | parent | context | favorite | on: Why can’t a bot tick the 'I'm not a robot' box?

You don’t, you wouldn’t even need a webcam, you could just splice into the video signal at output and interpret it directly (much as the HDCP bypasses do).