Tracking systems try to estimate world pose (position and orientation) of devices (e.g. head mounted displays, tablets) in real-time. An example use case could be the placement of furniture in Augmented Reality space.
The tracking systems integrated by ViewAR are using inside-out tracking, which is done entirely on the device, in contrast to outside-in where external sensors are used to estimate the devices pose.
Marker based tracking uses fixed marker images, which are recognized by the tracking systems in order to get the pose of devices. Markers can be QR-Codes, Magazines, Photos or any kind of 2D images. Markers have to be known by the tracking system before they can be recognized. Inaccuracies occur as soon as the marker is not visible in the camera frame, because pose information can not be updated. Therefore, extended tracking tries to estimate the pose of a marker even if it is not visible using additional methods.
Marker-less tracking uses camera input for detecting unique retrievable patterns (i.e. feature points) in the surrounding environment, for estimating the camera pose.
Furthermore, image processing algorithms are used for calculating 3D environmental information with use of motion. These software-based approaches are less accurate than dedicated 3D sensors, so hardware-based solutions are used for more accuracy.
With 3D object recognition and racking a real world object can be recognized and its pose estimated. Similarly to markers, the 3D target objects have to be know by the tracker.
Differences between tracking systems integrated by ViewAR
|Tracker||Target device||SLAM||Point cloud||Mesh generation||Marker tracking||3DObject recognition||Additional hardware needed|
|ARKit||iOS||Yes||Yes||(in progress)||Yes (ViewAR adds QR-Markers)||No||No|
|Wikitude||iOS, Android||Yes||No||No||YES (but not used)||No (Yes for Wikitude beta)||No|
|Kudan||iOS, Android||Yes (but not used)||No||No||Yes||No||No|
|Vuforia||iOS, Android, Windows||Yes (but not used)||No||No||Yes||No||No|
|Structure.io||iOS||Yes||Yes||Yes||combination with marker enabled tracker||No||Yes|
|HoloLens||Windows||Yes||Yes||(in progress)||(third party solution)||(third party solution)||Included|
|VisionLib +ARKit||iOS||Yes||Yes||No||Yes (ViewAR adds QR-Markers)||Yes||No|