# Is my algorithm about blob tracking for vehicle following correct?

I'm doing vehicles tracking project. The video is a one-way, no vehicles occlusion. After doing background subtraction, erosion and dilation, I get bounding box objects for each frame, and I can find $centroid(c_x,c_y)$ from that. So, the next thing I want to do is blobs tracking. Here is what I'm thinking on how to do the blobs tracking:

1. At first frame, store all (cx,cy,id)
2. Next frame, calculate distance each new (cx,cy) with each of old (cx,cy)
3. If distance < threshold, update the old (cx,cy) which qualify the formula
4. If distance > threshold, check if the cx,cy is near the entry coordinate (e.g. around x,y=0-640,0-40), if yes store new (cx,cy).

Is it right and possible to apply to tracking?

• Looks good. Suggested alternative technique in answer. – Manav Kataria Jan 18 '15 at 2:02
• What if the number of centroids increase or decrease? – Walid Ahmed Jan 5 '17 at 22:03