I was just informed that for our annual conference this year the presentation will be on Prezi instead of PowerPoint. I'm wondering what the "best" way to add a Prezi input into vMix is. Our PowerPoint setup had a dedicated laptop running PowerPoint, which shared its screen over NDI to vMix. That approach would clearly work for Prezi as well, but considering Prezi is web based, I was wondering if a vMix webpage input might be better. Prezi allows the user to be logged into another device to control advancing slides, so the laptop (or a mobile app) could still be used for that.

Here are my initial thoughts, but am interested if anyone else has done this and what they ended up doing.

Web Input advantages:
No reliance on NDI
Smoother animations and video playback
No risk of accidently showing something other than the clean presentation
The laptop is nothing but a remote Prezi session, the mobile app could also be used

NDI advantages:
More responsive slide advancement (theory crafting, but I assume that would be the case)
More traditional / safe approach
More flexibility if there is a last-minute ask to show unplanned content

I did a quick smoke test at my desk (our full setup is portable, so I only get it out a few days before the production).

It worked well, you get the live presentation link from Prezi and copy/paste it into the vMix web browser input. You have to click within vMix to accept cookies and then click the full screen arrow at the bottom right to hide the bottom status bar, but its only two clicks if you are okay with that. Once working, I would say the image is crystal clear, smooth, and works exactly as expected. There is a 0.1 - 0.2 second delay between advancing the slide with the remote session and seeing the change in vMix. Not enough to matter for a remote or even live audience, but could be an issue if the speaker is using a vMix output for their confidence monitor. It's just long enough of a delay that after clicking a handheld wireless presenter, you start wondering if it registered the click and might click it again. If you trust your speaker to not double-click, or have someone else advancing slides, it should be fine.

For our use case, I realized that I have a spare channel on my AJA ioX3, so I plan to use that with the presentation laptop's HDMI out. If I didn't have that, then I think the browser input option is probably less risky than NDI. I am sure we have all had situations where NDI works perfectly in tests, but on production day, you get the dreaded black screen because of a random network issue. The web browser method should work more consistently and opens up the possibility of the laptop controlling Prezi being on Wi-Fi, which you would never dream of doing with NDI. It's also a great option if you want to use an iPad on a podium for both speaker notes and a way to control the presentation.

TLDR, it works well, but make sure you test it for your use case.