This is a CameraX Feature Request to provide support to determine if the camera flash unit flash was fired -- primarily when flash mode is set to Auto.

Our current implementation makes use of CameraController.takePicture() via the ImageCapture.OnImageCapturedCallback(). Perhaps the flash result can be provided as an additional parameter to onCaptureSuccess(ImageProxy)

The goal is to set the appropriate Exif values for ExifInterface.TAG_FLASH. We can determine the flash mode prior to photo capture, but we are unable to determine if the flash fired or not.