The Mobile Vision API is now a part of ML Kit. We strongly encourage you to try it out, as it comes with new capabilities like on-device image labeling! Also, note that we ultimately plan to wind down the Mobile Vision API, with all new on-device ML capabilities released via ML Kit. Feel free to reach out to Firebase support for help.

GMVDataOutput Class

GMVDataOutput Class Reference

Overview

GMVDataOutput is a subclass of AVCaptureVideoDataoutput.

It is the abstract base class for GMV-based data outputs which filters the set of detection results. Once a feature has been detected and a delegate has been informed, that same feature is consistently delivered to that delegate until it disappears from the frame. Subclasses should overwrite the receivedRestuls: and cleanup: methods.

Inherits AVCaptureVideoDataOutput.

Inherited by GMVFocusingDataOutput, GMVMultiDataOutput, and GMVMultiDetectorDataOutput.

Instance Method Summary

(instancetype) - initWithDetector:
 Designated initializer. More...
 
(void) - receivedResults:
 Subclasses need to override these methods. More...
 
(void) - cleanup
 Clean up resources. More...
 

Property Summary

id< GMVDataOutputDelegatedataDelegate
 Data source information delegate. More...
 
AVCaptureDevicePosition captureDevicePosition
 Sets the camera device position to help calculate image rotation. More...
 
CGSize previewFrameSize
 The video frame preview size. More...
 
NSUInteger maxFrameGap
 The maximum allowable frames must pass without detecting a specific feature before delegate is notified the feature is no longer available. More...
 

Method Detail

- (instancetype) initWithDetector: (GMVDetector *)  NS_DESIGNATED_INITIALIZER

Designated initializer.

Parameters
detectoruse to run detection.
- (void) receivedResults: (NSArray< __kindof GMVFeature * > *)  results

Subclasses need to override these methods.

Detected GMVFeature results.

Parameters
resultsThe full detection results.
- (void) cleanup

Clean up resources.

Property Detail

- (id<GMVDataOutputDelegate>) dataDelegate
readwritenonatomicweak

Data source information delegate.

- (AVCaptureDevicePosition) captureDevicePosition
readwritenonatomicassign

Sets the camera device position to help calculate image rotation.

If not provided, it will try to retrieve position info through AVCaptureConnection.

- (CGSize) previewFrameSize
readnonatomicassign

The video frame preview size.

The value is used to normalize display properties.

- (NSUInteger) maxFrameGap
readwritenonatomicassign

The maximum allowable frames must pass without detecting a specific feature before delegate is notified the feature is no longer available.

The value is default to 3.