on my mac i tried turning zsnes emulator to full screen and it is black

Setup OBS, with chroma key if desired ( guide here).

Additionally you will ideally want a second monitor, because if any window or program moves in front of the capture area, it will be displayed on the video stream.

Unfortunately for Mac users, the quality of the video output from this method is much lower than the Windows method. We’ve kept the old CamTwist guide below, but it’s no longer the best method to use. The process to use the software is basically the same as the Windows method listed above. Update June 2020: There’s now a MacOS version of OBS VirtualCam. Update January 2021: VirtualCam is now natively included in OBS 26.1, so you no longer need to download the plugin listed below. Update January 2021: VirtualCam for MacOS is now natively included in OBS 26.1, so you no longer need to download any plugins. The mac section below has been updated with a link to it. Update June 2020: There is now an OBS virtual cam plugin for Mac. Until then we’re left with the following methods. It looks like this feature will soon be natively supported in OBS, as Tobi Lutke (the founder of Shopify) has just recently placed a $10,000 bounty for the feature. If you’re using Windows, then congratulations, the installation is quite simple! If you’re using MacOS then ideally you’ll need a second monitor and need to run multiple programs. The installation complexity will vary depending on your operating system. This is great if you’re giving company presentations, or just want to mess with your colleagues with a weird green screen background.

You might want to use OBS as a webcam source as it gives you a plethora of production options, such as picture in picture, chroma key (green screen) etc.

On my mac i tried turning zsnes emulator to full screen and it is black