MediaPipeTasksVision Framework Reference


protocol FaceDetectorLiveStreamDelegate : NSObjectProtocol

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

The delegate of FaceDetector must adopt FaceDetectorLiveStreamDelegate 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 FaceDetector is available.

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



    optional func faceDetector(_ faceDetector: MPPFaceDetector, didFinishDetection result: FaceDetectorResult?, timestampInMilliseconds: Int, error: Error?)



    The face detector which performed the face detection. This is useful to test equality when there are multiple instances of FaceDetector.


    The FaceDetectorResult object that contains a list of detections, each detection has a bounding box that is expressed in the unrotated input frame of reference coordinates system, i.e. in [0,image_width) x [0,image_height), which are the dimensions of the underlying image data.


    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.