MediaPipeTasksVision Framework Reference


protocol FaceLandmarkerLiveStreamDelegate : NSObjectProtocol

This protocol defines an interface for the delegates of FaceLandmarker face to receive results of performing asynchronous face detection on images (i.e, when runningMode = .liveStream).

The delegate of FaceLandmarker must adopt FaceLandmarkerLiveStreamDelegate protocol. The methods in this protocol are optional.

  • This method notifies a delegate that the results of asynchronous face detection of an image submitted to the FaceLandmarker is available.

    This method is called on a private serial dispatch queue created by the FaceLandmarker for performing the asynchronous delegates calls.



    func faceLandmarker(_ faceLandmarker: MPPFaceLandmarker, didFinishDetection result: FaceLandmarkerResult?, timestampInMilliseconds: Int, error: Error?)



    The face landmarker which performed the face landmark detctions. This is useful to test equality when there are multiple instances of FaceLandmarker.


    The FaceLandmarkerResult object that contains a list of landmarks.


    The timestamp (in milliseconds) which indicates when the input image was sent to the face detector.


    An optional error parameter populated when there is an error in performing face detection on the input live stream image data.