Image Tracker

Related documentations
Target Manager
Recommended Conditions for Target Images
Tracker Coordinate System

The Image Tracker recognizes and tracks planar images. It can demonstrate not only 3D objects but also videos, even the transparent one.

Create Instants
Start / Stop Tracker
Use Tracking Information
Set Target Image
Add / Replace Target Image
Change Tracking Mode

Create Instants

>ImageTrackerViewController.swift

var cameraDevice:MasCameraDevice = MasCameraDevice()
var trackingManager:MasTrackerManager = MasTrackerManager()

Start / Stop Tracker

To start / stop Tracker after loading the map, refer to the following code.

>ImageTrackerViewController.swift

@objc func resumeAR()
{
    ...
    trackingManager.start(.TRACKER_TYPE_IMAGE)
}

@objc func pauseAR()
{
    trackingManager.stopTracker()
    ...
}

Use Tracking Information

In the folder where SDK is installed, go to ‘data > SDKSample > Original > ImageTarget' folder, and there is sample target image. Print the image.

If you use the sample code, the following content will be augmented for each image.

  • Blocks.jpg: The alpha video is augmented.
  • Lego.jpg: The normal video is augmented.
  • Glacier.jpg: The cube with the texture is augmented.

To apply tracking results to augmented objects, refer to the following code.

>ImageTrackerViewController.swift

override func glkView(_ view: GLKView, drawIn rect: CGRect) {
        ...
        let trackingState:MasTrackingState = trackingManager.updateTrackingState()
        let result:MasTrackingResult = trackingState.getTrackingResult()

       let backgroundImage:MasTrackedImage = trackingState.getImage()
        let backgroundProjectionMatrix:matrix_float4x4 = cameraDevice.getBackgroundPlaneProjectionMatrix()
        
        glEnable(GLenum(GL_DEPTH_TEST))
        
        let projectionMatrix:matrix_float4x4 = cameraDevice.getProjectionMatrix()
        
        let trackingCount:Int32 = result.getCount()
        
        if trackingCount > 0 {
            for i in stride(from: 0, to: trackingCount, by: 1) {
                let trackable:MasTrackable = result.getTrackable(i)
                
                if trackable.getName() == "Lego" {
                    if videoCaptureController.getState() == MEDIA_STATE.PLAYING {
                        videoCaptureController.play()
                        videoCaptureController.update()
                        
                        videoPanelRenderer.setProjectionMatrix(projectionMatrix: projectionMatrix)
                        videoPanelRenderer.setPoseMatrix(poseMatrix: trackable.getPose())
                        videoPanelRenderer.setTranslation(x: 0.0, y: 0.0, z: 0.0)
                        videoPanelRenderer.setScale(x: 0.26, y: -0.15, z: 1.0)
                        videoPanelRenderer.draw(videoTextureId: videoCaptureController.getOpenglesTextureId())
                    }
                } else if trackable.getName() == "Blocks" {
                    if chromakeyVideoCaptureController.getState() == MEDIA_STATE.PLAYING {
                        chromakeyVideoCaptureController.play()
                        chromakeyVideoCaptureController.update()
                        
                        chromakeyVideoPanelRenderer.setProjectionMatrix(projectionMatrix: projectionMatrix)
                        chromakeyVideoPanelRenderer.setPoseMatrix(poseMatrix: trackable.getPose())
                        chromakeyVideoPanelRenderer.setTranslation(x: 0.0, y: 0.0, z: 0.0)
                        chromakeyVideoPanelRenderer.setScale(x: 0.26, y: -0.18, z: 1.0)
                        chromakeyVideoPanelRenderer.draw(videoTextureId: chromakeyVideoCaptureController.getOpenglesTextureId())
                    }
                } else if trackable.getName() == "Glacier" {
                    textureCube.setProjectionMatrix(projectionMatrix: projectionMatrix)
                    textureCube.setPoseMatrix(poseMatrix: trackable.getPose())
                    textureCube.setTranslation(x: 0.0, y: 0.0, z: -0.025)
                    textureCube.setScale(x: 0.15, y: 0.15, z: 0.05)
                    textureCube.draw()
                } else {
                    coloredCube.setProjectionMatrix(projectionMatrix: projectionMatrix)
                    coloredCube.setPoseMatrix(poseMatrix: trackable.getPose())
                    coloredCube.setTranslation(x: 0.0, y: 0.0, z: -0.025)
                    coloredCube.setScale(x: 0.15, y: 0.15, z: 0.005)
                    coloredCube.draw()
                }
            }
        }
        else {
            videoCaptureController.pause()
            chromakeyVideoCaptureController.pause()
        }
        
        glDisable(GLenum(GL_DEPTH_TEST))
        
    }

Set Target Image

By calling function addTrackerData to register the map file and calling function loadTrackerData, the target image can be tracked. To set a target image, refer to the following code.

>ImageTrackerViewController.swift

func startEngin()
{
    ...
    let blocksTrackerMapPath:String = Bundle.main.path(forResource: "Blocks", ofType: "2dmap", inDirectory: "data/SDKSample")!
    let glacierTrackerMapPath:String = Bundle.main.path(forResource: "Glacier", ofType: "2dmap", inDirectory: "data/SDKSample")!
    let legoTrackerMapPath:String = Bundle.main.path(forResource: "Lego", ofType: "2dmap", inDirectory: "data/SDKSample")!
        
    trackingManager.start(.TRACKER_TYPE_IMAGE)
    trackingManager.setTrackingOption(.NORMAL_TRACKING)
    trackingManager.addTrackerData(blocksTrackerMapPath)
    trackingManager.addTrackerData(glacierTrackerMapPath)
    trackingManager.addTrackerData(legoTrackerMapPath)
        
    trackingManager.loadTrackerData()
}

Add / Replace Target Image

  1. Create a map file refer to Target Manager.

  2. Download the file you created.

  3. Unzip the downloaded file and copy it to the desired path.

  4. Set a target image.

Change Tracking Mode

5 Tracking Modes of Image Tracker:

NORMAL_TRACKING, EXTENDED_TRACKING, MULTI_TRACKING, JITTER_REDUCTION_ACTIVATION, JITTER_REDUCTION_DEACTIVATIO

  • NORMAL_TRACKING: Default Setting. Traceable one target image.
trackingManager.setTrackingOption(.NORMAL_TRACKING)
  • EXTENDED_TRACKING: Traceable even at the far distance from the target image.
trackingManager.setTrackingOption(.EXTENDED_TRACKING)
  • MULTI_TRACKING: Possible to recognize and track up to three target images at the same time.
trackingManager.setTrackingOption(.MULTI_TRACKING)
  • JITTER_REDUCTION_ACTIVATION: Jitter reduction.
trackingManager.setTrackingOption(.JITTER_REDUCTION_ACTIVATION)
  • JITTER_REDUCTION_DEACTIVATION: Disable the jitter reduction option.
trackingManager.setTrackingOption(.JITTER_REDUCTION_DEACTIVATION)