> For the complete documentation index, see [llms.txt](https://docs.engagevr.io/engage/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.engagevr.io/engage/experience-editor/videos-and-screens/chroma-key-screens.md).
# Chroma key screens
Chroma key screens display a chosen color as transparent. You can use these screens with what are commonly referred to as green-screen videos. For example, you can record a person against a solid color background, and then, when you play that video on a chroma key screen, they will appear as though they are standing in the environment.
## Adding a chroma key screen to an experience
1. If the timeline view isn't active in the editor panel, select the timeline icon (
).
2. From the panel on the left-hand side, select 
**IFX**.
3. From the library of IFX, select a screen that includes **chroma key** in its title.
4. Place the IFX in the environment. For more information about the controls that are available when you add an IFX, see [Adding IFX](/engage/advanced-features/using-ifx/adding-ifx.md).
## Chroma key screen effect options
For instructions on how to access effect options, see [Effect options](/engage/experience-editor/working-with-objects/effect-options.md). Additional settings depend on whether the chroma key screen uses shared media or an external URL. For more information, see [Shared media screens](/engage/experience-editor/videos-and-screens/shared-media-screens.md#shared-media-screen-effect-options) or [External URL screens](/engage/experience-editor/videos-and-screens/external-url-screens.md#external-url-screen-effect-options).
All chroma key screens include an option to set which color in the video will be transparent.
* To set the transparency color, select **Choose Color**, select a color in the **Color Picker**, and then select **OK**.
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