Multi-Object Tracking
Multi-Object Tracking (MOT) is the task of estimating the trajectory of multiple unique objects in a video — assigning a unique ID to each detected object and maintaining that ID even as objects cross paths, are occluded, or move erratically.
What Is MOT?
- Paradigm: Detection-by-Tracking vs. Tracking-by-Detection.
- Standard Pipeline:
1. Detect objects in current frame (YOLO).
2. Extract features (Re-ID embedding + Motion/Kalman Filter).
3. Associate with existing tracks (Hungarian Algorithm).
- Metric: MOTA (Multiple Object Tracking Accuracy), IDF1.
Why It Matters
- Traffic Monitoring: Counting distinct cars, not just detections per frame.
- Crowd Analysis: Tracking flow of people in public spaces.
- Retail: Tracking customer paths through a store ("Customer Flow").
Key Failure Mode: ID Switch. When two people cross paths and the tracker swaps their IDs.
Multi-Object Tracking is converting perception into identity — turning raw detections into persistent, trackable entities.