Show text on an image
UseCamera ... EndCamera UseCamera["background"] ... EndCamera
... is the code you want to run on each frame in the image.
UseCamera has two modes:
UseCamera: Runs all enclosed commands in a single thread. This is ideal for real-time use cases.
UseCamera["background"]: Shows the webcam in one thread and runs commands in another thread. This allows you to add asynchronous logic (i.e. a 3, 2, 1 countdown) without freezing the webcam feed while the logic runs.
The following example loads a webcam, turns each frame greyscale, and shows the resultant frame:
UseCamera Greyscale Show