ImageTracker Class¶

Description¶

ImageTracker implements image target detection and tracking.

ImageTracker occupies (1 + SimultaneousNum) buffers of camera. Use setBufferCapacity of camera to set an amount of buffers that is not less than the sum of amount of buffers occupied by all components. Refer to Overview _ .

After creation, you can call start/stop to enable/disable the track process. start and stop are very lightweight calls.

When the component is not needed anymore, call close function to close it. It shall not be used after calling close.

ImageTracker inputs FeedbackFrame from feedbackFrameSink. FeedbackFrameSource shall be connected to feedbackFrameSink for use. Refer to Overview _ .

Before a Target can be tracked by ImageTracker, you have to load it using loadTarget/unloadTarget. You can get load/unload results from callbacks passed into the interfaces.

isAvailable¶

Returns true.

C: bool easyar_ImageTracker_isAvailable(void)¶

C++17: static bool isAvailable()¶

Traditional C++: static bool isAvailable()¶

Java: public static boolean isAvailable()¶

Kotlin: companion object fun isAvailable(): Boolean¶

Objective-C: + (bool)isAvailable¶

Swift: public static func isAvailable() -> Bool¶

C#: public static bool isAvailable()¶

feedbackFrameSink¶

FeedbackFrame input port. The InputFrame member of FeedbackFrame must have raw image, timestamp, and camera parameters.

C: void easyar_ImageTracker_feedbackFrameSink(easyar_ImageTracker * This, easyar_FeedbackFrameSink * * Return)¶

C++17: std::shared_ptr<FeedbackFrameSink> feedbackFrameSink()¶

Traditional C++: void feedbackFrameSink(FeedbackFrameSink * * Return)¶

Java: public @Nonnull FeedbackFrameSink feedbackFrameSink()¶

Kotlin: fun feedbackFrameSink(): FeedbackFrameSink¶

Objective-C: - (easyar_FeedbackFrameSink *)feedbackFrameSink¶

Swift: public func feedbackFrameSink() -> FeedbackFrameSink¶

C#: public virtual FeedbackFrameSink feedbackFrameSink()¶

bufferRequirement¶

(since 3.1.0)

Camera buffers occupied in this component.

C: int easyar_ImageTracker_bufferRequirement(easyar_ImageTracker * This)¶

C++17: int bufferRequirement()¶

Traditional C++: int bufferRequirement()¶

Java: public int bufferRequirement()¶

Kotlin: fun bufferRequirement(): Int¶

Objective-C: - (int)bufferRequirement¶

Swift: public func bufferRequirement() -> Int32¶

C#: public virtual int bufferRequirement()¶

outputFrameSource¶

OutputFrame output port.

C: void easyar_ImageTracker_outputFrameSource(easyar_ImageTracker * This, easyar_OutputFrameSource * * Return)¶

C++17: std::shared_ptr<OutputFrameSource> outputFrameSource()¶

Traditional C++: void outputFrameSource(OutputFrameSource * * Return)¶

Java: public @Nonnull OutputFrameSource outputFrameSource()¶

Kotlin: fun outputFrameSource(): OutputFrameSource¶

Objective-C: - (easyar_OutputFrameSource *)outputFrameSource¶

Swift: public func outputFrameSource() -> OutputFrameSource¶

C#: public virtual OutputFrameSource outputFrameSource()¶

create¶

Creates an instance. The default track mode is ImageTrackerMode.PreferQuality .

C: void easyar_ImageTracker_create(easyar_ImageTracker * * Return)¶

C++17: static std::shared_ptr<ImageTracker> create()¶

Traditional C++: static void create(ImageTracker * * Return)¶

Java: public static @Nonnull ImageTracker create()¶

Kotlin: companion object fun create(): ImageTracker¶

Objective-C: + (easyar_ImageTracker *)create¶

Swift: public static func create() -> ImageTracker¶

C#: public static ImageTracker create()¶

createWithMode¶

Creates an instance with a specified track mode. On lower-end phones, ImageTrackerMode.PreferPerformance can be used to keep a better performance with a little quality loss.

C: void easyar_ImageTracker_createWithMode(easyar_ImageTrackerMode trackMode, easyar_ImageTracker * * Return)¶

C++17: static std::shared_ptr<ImageTracker> createWithMode(ImageTrackerMode trackMode)¶

Traditional C++: static void createWithMode(ImageTrackerMode trackMode, ImageTracker * * Return)¶

Java: public static @Nonnull ImageTracker createWithMode(int trackMode)¶

Kotlin: companion object fun createWithMode(trackMode: Int): ImageTracker¶

Objective-C: + (easyar_ImageTracker *)createWithMode:(easyar_ImageTrackerMode)trackMode¶

Swift: public static func createWithMode(_ trackMode: ImageTrackerMode) -> ImageTracker¶

C#: public static ImageTracker createWithMode(ImageTrackerMode trackMode)¶

start¶

Starts the track algorithm.

C: bool easyar_ImageTracker_start(easyar_ImageTracker * This)¶

C++17: bool start()¶

Traditional C++: bool start()¶

Java: public boolean start()¶

Kotlin: fun start(): Boolean¶

Objective-C: - (bool)start¶

Swift: public func start() -> Bool¶

C#: public virtual bool start()¶

stop¶

Stops the track algorithm. Call start to start the track again.

C: void easyar_ImageTracker_stop(easyar_ImageTracker * This)¶

C++17: void stop()¶

Traditional C++: void stop()¶

Java: public void stop()¶

Kotlin: fun stop(): Unit¶

Objective-C: - (void)stop¶

Swift: public func stop() -> Void¶

C#: public virtual void stop()¶

close¶

Close. The component shall not be used after calling close.

C: void easyar_ImageTracker_close(easyar_ImageTracker * This)¶

C++17: void close()¶

Traditional C++: void close()¶

Java: public void close()¶

Kotlin: fun close(): Unit¶

Objective-C: - (void)close¶

Swift: public func close() -> Void¶

C#: public virtual void close()¶

loadTarget¶

Load a Target into the tracker. A Target can only be tracked by tracker after a successful load.

This method is an asynchronous method. A load operation may take some time to finish and detection of a new/lost target may take more time during the load. The track time after detection will not be affected. If you want to know the load result, you have to handle the callback data. The callback will be called from the thread specified by CallbackScheduler . It will not block the track thread or any other operations except other load/unload.

C: void easyar_ImageTracker_loadTarget(easyar_ImageTracker * This, easyar_Target * target, easyar_CallbackScheduler * callbackScheduler, easyar_FunctorOfVoidFromTargetAndBool callback)¶

C++17: void loadTarget(std::shared_ptr<Target> target, std::shared_ptr<CallbackScheduler> callbackScheduler, std::function<void(std::shared_ptr<Target>, bool)> callback)¶

Traditional C++: void loadTarget(Target * target, CallbackScheduler * callbackScheduler, FunctorOfVoidFromTargetAndBool callback)¶

Java: public void loadTarget(@Nonnull Target target, @Nonnull CallbackScheduler callbackScheduler, @Nonnull FunctorOfVoidFromTargetAndBool callback)¶

Kotlin: fun loadTarget(target: Target, callbackScheduler: CallbackScheduler, callback: FunctorOfVoidFromTargetAndBool): Unit¶

Objective-C: - (void)loadTarget:(easyar_Target *)target callbackScheduler:(easyar_CallbackScheduler *)callbackScheduler callback:(void (^)(easyar_Target * target, bool status))callback¶

Swift: public func loadTarget(_ target: Target, _ callbackScheduler: CallbackScheduler, _ callback: @escaping (Target, Bool) -> Void) -> Void¶

C#: public virtual void loadTarget(Target target, CallbackScheduler callbackScheduler, Action<Target, bool> callback)¶

unloadTarget¶

Unload a Target from the tracker.

This method is an asynchronous method. An unload operation may take some time to finish and detection of a new/lost target may take more time during the unload. If you want to know the unload result, you have to handle the callback data. The callback will be called from the thread specified by CallbackScheduler . It will not block the track thread or any other operations except other load/unload.

C: void easyar_ImageTracker_unloadTarget(easyar_ImageTracker * This, easyar_Target * target, easyar_CallbackScheduler * callbackScheduler, easyar_FunctorOfVoidFromTargetAndBool callback)¶

C++17: void unloadTarget(std::shared_ptr<Target> target, std::shared_ptr<CallbackScheduler> callbackScheduler, std::function<void(std::shared_ptr<Target>, bool)> callback)¶

Traditional C++: void unloadTarget(Target * target, CallbackScheduler * callbackScheduler, FunctorOfVoidFromTargetAndBool callback)¶

Java: public void unloadTarget(@Nonnull Target target, @Nonnull CallbackScheduler callbackScheduler, @Nonnull FunctorOfVoidFromTargetAndBool callback)¶

Kotlin: fun unloadTarget(target: Target, callbackScheduler: CallbackScheduler, callback: FunctorOfVoidFromTargetAndBool): Unit¶

Objective-C: - (void)unloadTarget:(easyar_Target *)target callbackScheduler:(easyar_CallbackScheduler *)callbackScheduler callback:(void (^)(easyar_Target * target, bool status))callback¶

Swift: public func unloadTarget(_ target: Target, _ callbackScheduler: CallbackScheduler, _ callback: @escaping (Target, Bool) -> Void) -> Void¶

C#: public virtual void unloadTarget(Target target, CallbackScheduler callbackScheduler, Action<Target, bool> callback)¶

targets¶

Returns current loaded targets in the tracker. If an asynchronous load/unload is in progress, the returned value will not reflect the result until all load/unload finish.

C: void easyar_ImageTracker_targets(const easyar_ImageTracker * This, easyar_ListOfTarget * * Return)¶

C++17: std::vector<std::shared_ptr<Target>> targets()¶

Traditional C++: void targets(ListOfTarget * * Return)¶

Java: public java.util.@Nonnull ArrayList<@Nonnull Target> targets()¶

Kotlin: fun targets(): ArrayList<Target>¶

Objective-C: - (NSArray<easyar_Target *> *)targets¶

Swift: public func targets() -> [Target]¶

C#: public virtual List<Target> targets()¶

setSimultaneousNum¶

Sets the max number of targets which will be the simultaneously tracked by the tracker. The default value is 1.

C: bool easyar_ImageTracker_setSimultaneousNum(easyar_ImageTracker * This, int num)¶

C++17: bool setSimultaneousNum(int num)¶

Traditional C++: bool setSimultaneousNum(int num)¶

Java: public boolean setSimultaneousNum(int num)¶

Kotlin: fun setSimultaneousNum(num: Int): Boolean¶

Objective-C: - (bool)setSimultaneousNum:(int)num¶

Swift: public func setSimultaneousNum(_ num: Int32) -> Bool¶

C#: public virtual bool setSimultaneousNum(int num)¶

simultaneousNum¶

Gets the max number of targets which will be the simultaneously tracked by the tracker. The default value is 1.

C: int easyar_ImageTracker_simultaneousNum(const easyar_ImageTracker * This)¶

C++17: int simultaneousNum()¶

Traditional C++: int simultaneousNum()¶

Java: public int simultaneousNum()¶

Kotlin: fun simultaneousNum(): Int¶

Objective-C: - (int)simultaneousNum¶

Swift: public func simultaneousNum() -> Int32¶

C#: public virtual int simultaneousNum()¶