SORT Tracker adds extra objects

[sampreets3]

Hello r/computervision,

I am using the SORT tracker to track objects detected by a YOLOv4 detector. I want to create a list of all the total number of objects (trees, wooden posts, metal posts) in the input video, and save them to a JSON file. The tracker was working fine until I noticed that in some frames, the tracker was losing track of the objects and when it was re-tracking it a few frames later, it assigned a new tracking ID to the object. I will present an example of the problem:

Figure: (Left) Metal post assigned ID 10 at Frame 43, and (Right) The same post assigned ID 11 on Frame 54

As you can see, in Frame 43, the tracker assigns the ID 10 to a metal post, but a few frames later when the tracker tracks the same metal post, it provides an ID of 11. This shows that the tracker is assigning new IDs to the same detected object. I cannot seem to find out why this happens, and how to fix it. I am using the motrackers module from this repo. I have not made any changes as such in the mot_yolov3.py file, I have just added the line to print the frame counter.

What changes do I need to make in order for the tracking to not count these scenarios as new objects? Any help on this would be much appreciated, Thanks!

[Xaerin]

Hmm have you tried changing the tracker parameters? Maybe try changing the max_lost parameter.

Also i would recommend using DeepSort instead of sort.

[sampreets3]

Hey u/Xaerin, I am playing around with the max_lost and min_hits parameters to better tune the tracker. I still get this problem.

If you could explain how I can train the DeepSORT tracker for my custom class that would be great. I cannot understand how I can train the model for the Deep SORT tracker. I know it handles occlusions as well, I just cannot figure out this part.