MediaPipeTasksVision Framework Reference

MPPObjectDetectorLiveStreamDelegate

@protocol MPPObjectDetectorLiveStreamDelegate <NSObject>

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

The delegate of ObjectDetector must adopt ObjectDetectorLiveStreamDelegate protocol. The methods in this protocol are optional.

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

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

    Declaration

    Objective-C

    - (void)objectDetector:(nonnull MPPObjectDetector *)objectDetector
    didFinishDetectionWithResult:(nullable MPPObjectDetectorResult *)result
         timestampInMilliseconds:(NSInteger)timestampInMilliseconds
                           error:(nullable NSError *)error;

    Parameters

    objectDetector

    The object detector which performed the object detection. This is useful to test equality when there are multiple instances of ObjectDetector.
    result

    The ObjectDetectorResult 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.
    timestampInMilliseconds

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

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