Just a quick tip for the brave people out there... Maybe you are already using this solution (or a similar one), but for the ones that aren't, here are my two cents. If you install OBS (open source equivalent to X-Split) and OBS-Virtualcam (an add-on), you can use the OBS virtual camera thus installed instead of the physical webcam in Roll20. In OBS, you can then set different backgrounds, even videos, show portraits of NPCs, your GM face, etc. Everything is basically real-time. I use it to show the players the landscape when they travel, the weather, the interior of the places they visit and the NPCs faces without resorting to handouts. You can also show your own live face above the pictures/videos of your choice, but of course you need a chroma key background to obtain a nice result. That's it. If you are interested and need more info, I can make a video to show the procedure (and the results). Just let me know.