How to setup with OBS for Captioning or Subtitling a Livestream

This tutorial assumes you have OBS installed and a session created. We will use automatic captioning/translation in this example, but other methods for releasing subtitles like manuscripts can work just as well.

Step 1: Setup automatic captioning/translation

You can use either the raw captioning setup (for captioning only) or the auto-caption + translate setup. Follow the instructions linked above then return here.

Step 2: Open the projector view for your session

Click on the “Start Projector” button for the session.

Step 3: Configure subtitles and enable chroma key background

In the projector controller, open the subtitles/closed captioning configuration.

Ensure “Enable display” is active. Change settings to make the subtitles/captions look the way you want. For example, many people choose to enable “Scroll” and “Text shadow” for visibility.

Click on the Chroma Key background button. This will change the background color of your projector view to be the chroma key color. The default green color is sufficient.

Step 4: Open OBS and add the projector view as a window source

In the Sources panel of OBS, click on the plus sign at the bottom and select “Window Capture”.

You will see a list of windows that you can add to the Scene. Select the Projector View window and press “OK”.

Step 5: Apply the chroma key filter and crop the window

Drag the Window Capture source you added to the top of the list of Sources. This ensures the subtitles will be visible.

Next right click on the Window Capture source and select “Filters” from the menu.

In the lower half of the Filters window, you will see a list of “Effect Filters”. Click on the plus sign and add a “Chroma Key” filter.

By default it will select the Green “Key Color Type” which matches the chroma key color of’s projector view.

Close the filters window.

Now in your OBS preview you should be able to see through the projector view to the rest of your Scene. However, the browser address bar and part of the bottom of the projector view may still cover up part of your scene.

Let’s hide these unwanted screen elements.

To do so, right click on your Window Capture source. In the menu, go to “Transform” and click on “Edit Transform”.

You will see a window that lets you crop the top and bottom of your window. Increase the top and bottom crop amounts until the unwanted parts of the projector view are no longer visible in the preview.

Now your preview should look something like the image below.

Step 6: Speak and see the subtitles in OBS!

To test if the captions or subtitles are appearing in our OBS preview, ensure that the microphone is on in and begin speaking. You should see the words appear in OBS in the lower third of the screen!


There are several ways to generate captions and subtitles with ranging from automatic to script based to integrating with a stenographer. All of them can be shown through the projector view and integrated with OBS as described in this tutorial.

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