[pdpi]

The elgato is doing something completely straightforward — video output to video input, done. With only a few details, it’s almost like a regular webcam where the controller is in the usb plug rather than the webcam’s body.

The SD thing has all sorts of nastiness to it.

First, you won’t have a standard usb video input, so you’re going to need to do a bunch of awkward driver work to get applications to consume the video feed.

Second, you’ll have to deal with the lag and jittery video that you get because the camera will almost certainly buffer writes.

Then you have to figure out how to get the controller in the SD reader to understand the incoming writes, which it was most certainly not designed to do.