To get started with our automated labelling features, click on the 'Automated labelling' button to expand the 'Automated labelling' drawer.
Automated labelling drawer
Here you will find ‘Classification’, ‘Detection and segmentation’, and ‘Tracking and interpolation.’ We'll cover tracking and interpolation on this page - for 'Classification' and 'Detection and segmentation', please navigate to the 'Inference' page.
Tracking and interpolation
Let’s learn how to propagate an object through frames with tracking and interpolation.
Our tracking algorithms will follow the object through frames using the pixel information enclosed in the object boundary. All tracking algorithms propagate boxes forward through frames, and objects in lower number frames can thus only be tracked to higher number frames. Interpolation, by contrast, works by interpolating the box or polygon boundary itself in between frames where they are drawn.
Let’s first try to track an object. First pick the objects you want tracked under ‘Video labels’. You can pick as many objects as you want to run the tracker with.
The ‘Tracking annotation interval’ is a parameter for how many frames you want the tracker to run after it sees an object. It will thus stop that particular track after the number of frames specified. Tracking range specifies which part of the data unit you want the tracker to work on to avoid the algorithm from running on the whole data unit. By setting the tracking range to a specified interval, the tracker will only consume and produce labels within that interval.
So for example: We have a bounding box for Object A drawn on frames 10 and 40. Setting the ‘Tracking range’ [10,40] and the ‘Tracking annotation interval’ to 30 you will get Object A on all frames 10-40.
Setting the ‘Tracking range’ [20,40] and ‘Tracking interval’ to 30 you will get no additional instances of Object A added because the ‘Tracking range’ will miss the annotated object on frame 10.
Setting the ‘Tracking annotation interval’ to 20 and ‘Tracking range [10,40] you will get Object A on frames 10-30 and on frame 40 since the tracker will run 20 frames from frame 10 and then stop that track.
You can also run the tracker directly from the hotkeys. Highlight the object you want to track and press ‘Ctrl + T’ to run the tracker on that object. The tracker will run from the frame you are on and will default to a ‘Tracking interval’ of 30 frames. This default can be altered through the Settings icon in the upper right panel.
Finally, you can select different possible tracking algorithms under ‘Advanced settings’. We offer ‘Advanced’, ‘Standard’, and ‘Simple’ as selections. ‘Advanced’ tends to have the highest tracking accuracy but is the slowest in terms of computation time. ‘Simple’ runs very quickly but has the lowest accuracy. ‘Standard’ sits in between ‘Advanced’ and ‘Simple’ in both speed and accuracy.
Now let’s run interpolation. Again select as many objects as you want interpolated. The ‘Interpolation range’ is the range of frames in the data unit the algorithm will run on. In case there is at least two instances of an object you selected within the range of frames you set the interpolation will fill in all empty frames in between these instances.
Interpolation works for both bounding boxes and polygons.