Multi Source Video in MS Teams without an actual green screen

My objective: show a video feed in MS Teams that consists of me and a combinati0n of other sources — such as desktop applications like Powerpoint, images, videoclips etc. Without using a green screen or other tools — with nothing more than a laptop with webcam.

I made this work with the use of two free tools: OBS (Open Broadcaster Software) 26.0.1 and the Zoom client application. This next picture shows what setup I used.

A regular Windows 10 laptop with webcam and the following software tools: Zoom Client, Powerpoint (as an example source), OBS and MS Teams. To prepare, I created an image file (green.jpeg) that is just a green rectangle that will serve as a virtual green screen that is use as virtual background in Zoom

There are a few tricks to apply and steps to take:


Sign up for a free account on Zoom

Download Zoom Client

Open Zoom session — just for me, in my personal Zoom Chat Room

Start Video

Add the green.jpeg as a new Virtual Background (Open Video Settings pane)

Next I had to revolve an issue with the video output in Zoom not being captured properly in OBS — using this thread.

On the video pane in Zoom

click on Advanced and select a rendering mode

that is not a flip mode.

OBS Studio

In OBS, add two sources: Zoom and Powerpoint slide show

Zoom as Window Source -

select Zoom Window as source. Then add a Chroma Key filter to this source — to remove the virtual green screen behind me.

Set up the Powerpoint Slide Show with Show Type “Browsed by an individual (window)”; this seems to be the only way for OBS to capture a running Powerpoint Slideshow.

The start the slideshow and add the slideshow as source in OBS.

The Powerpoint slides are shown mirrored in Teams. To fix that, add a Transform action to the Powerpoint source of type Flip Horizontal.

The slides now show up mirrored in OBS and okay in Teams. (there might be an easier way to fix this — but I have not yet found it). It looks weird in OBS — but okay in Teams

Finally in OBS, start the virtual camera. That will make the output from OBS available as camera feed to applications that can use camera feed as input — such as Teams.


Finally, in MS Teams, open the Device Settings pane.

select OBS Virtual Camera as the camera source.

Now the output from OBS Studio is used as the camera feed in MS Teams — my head taken from the webcam through Zoom and the Powerpoint slideshow — mixed together in OBS Studio. More sources can be mixed and I can create multiple scenes ni OBS to switch between — with different compositions of different or the same sources and different filters applied. :

Now I can start dazzling my colleagues in Teams sessions with every changing and even moving (add video source in OBS) background.

Originally published at on October 9, 2020.

Lucas Jellema is solution architect and CTO at AMIS, The Netherlands. He is Oracle ACE Director, Groundbreaker Ambassador, JavaOne Rockstar and programmer