You can use the video of someone's face when they're using the effect as a texture in your scene, by extracting the face tracker texture.
You can then apply the texture to a material and object - for example, to create a face swap effect.
To use the video captured of the entire scene, use the camera texture instead.
You'll see a texture called faceTracker0 in the Assets panel:
If you select the texture in the Assets panel, you'll be able to see and edit its properties in the Inspector.
There are 2 options to choose from here.
Use this option to create a 3D representation of the user's face. You'd generally use this mode when applying the texture to a face mesh, for example in a face swap effect.
This mode will create a flat cutout of the face. You could use this mode to create 2D animations featuring the user's face.
If the texture is applied to a face mesh, check the boxes next to Eyes and Mouth. This will make sure the texture aligns properly with the face mesh.
Start by adding the face trackers:
Then, edit the second face tracker so that it responds to the second face to appear in the scene:
Next, create the face mesh, textures and materials:
The face mesh will have hard edges. To blend these with the face, use the face mesh mask included in the face reference assets.