The base callback interface for interacting with the recognition service, extended by the IDataCaptureService.Callback and ITextCaptureService.Callback interfaces.
public static interface IRecognitionService.Callback
Note: While the service is being stopped, frames continue to be requested and calls to this callback continue to be queued, so this callback can be called after the service has been stopped.
Called to report an error.
Called to request the latest video frame.