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I'm trying to implement a camera-based barcode scanner on Android (using CameraX and MLKit). I want to limit the recognized barcodes to a viewfinder frame in the center of the screen, but the returned bounding box has quite weird coordinates, and I don't know how to convert them to match the viewfinder coordinates.
The viewfinder view (and the whole camera screen) is in Compose.

 Better try in <#C04TPPEQKEJ|compose-android> 

try <https://developer.android.com/reference/androidx/camera/view/LifecycleCameraController|LifecycleCameraController> and wrap you analyzer in <https://developer.android.com/reference/androidx/camera/mlkit/vision/MlKitAnalyzer|MlkitAnalyzer>, this may help you with coordinates transformation.

Turned out indeed using `LifecycleCameraController` and `MlKitAnalyzer` with `CameraController.COORDINATE_SYSTEM_VIEW_REFERENCED` fixed the problem!
Then (I'm using Compose) I just had to translate the pixel coordinates from the camera to `dp` units using `LocalDensity.current`.
Thanks again for your valuable suggestion.
Also this article explains very well the separation of responsibilities in CameraX between `PreviewView` and `CameraController`:
<https://medium.com/androiddevelopers/camerax-learn-how-to-use-cameracontroller-e3ed10fffecf>

Example solution in Compose in this StackOverflow answer:
<https://stackoverflow.com/a/77698616/4990683>

I'm glad it helped you resolve the issue! Thanks for sharing your experience.