For this demo project, I used yolov5m.onnx, OpenCV, and customized sort.py from Alex Bewley’s SORT algorithm(simple online and real-time tracking).

Link: https://github.com/abewley/sort

I used a simple video for tracking (partial implementation) but if you use a complex video (When CCTV is closer and there is so much occlusion throughout the video), customized sort.py might throw errors and entire frames of the video won't be processed.

You can also implement this repo having been modified main.py in other projects i.e. Traffic_Surveillance, etc. The screenshot provided below is produced by the same repo after some minor modification.

Below is the gist of how to instantiate and update SORT. See the 'main' section of sort.py for a complete example.

from sort import *

#create instance of SORT
mot_tracker = Sort() 

# get detections
...

# update SORT
track_bbs_ids = mot_tracker.update(detections)

# track_bbs_ids is a np array where each row contains a valid bounding box and track_id (last column)
...