This tutorial is a walkthrough to track points of interest in a live video.
Important : please note that this feature is exclusive to Millumin V3.
Camera
To follow this tutorial, you need a camera. You can use your laptop webcam to perform a test, but it is not the best equipment to do so. Mainly because this camera constantly adapts luminosity.
When doing a tracking, the camera resolution is not the most important parameter. 600px wide is ok for most applications.
The latency of the camera is important. To compare latency, film a timecode in Millumin and take a screenshot to compare. Here for example, there is 14 frames of latency with a smartphone camera :
Lighting
This is the most important part in tracking. The more difference of luminosity between the tracked points and the background, the easiest the tracking is.
Having a constant lighting will also make tracking more efficient.
The tracking effect
In your Millumin's layer, go to the effect section and select blob tracking :
In the settings, switch view-mode to "Threshold", and adjust the threshold parameter until only your point of interest persists :
Then, switch view-mode to "Blobs". The goal here is to be sure that your point of interest is never lost. You can adjust "radius min" and "radius max" for that.
If you are tracking more than one point, you can go to the tracking view and adjust "merge at" parameter. This parameter will merge two blobs (consider them as one) if its centers are close. You can put this parameter to 0 to deactivate this behavior.
Here is an example with a static image. At some point, increasing "merge at" tells the effect that those two points are only one :
You can now switch view-mode to "Tracking + Original" and test your tracking.
Once done, you can open the interaction-panel (CMD+M) and add some interactions on whatever you want (typically X and Y of a layer). To learn more about interactions, you can read this tutorial.
Finally, you can downscale the analysis resolution by lowering the "Downsize" parameter. This will lighten the process.
If the blob is a bit noisy, adjust the "Stabilization" parameter. Keep in mind that the more you increase this parameter, the less the tracking is reactive.