Camera Mounting Requirements¶

🎯 Camera Mounting Height¶

Minimum installation height: 4 meters
Recommended height:
4–5 m for standard cross-sections and smaller intersections
6–7 m for large intersections and roundabouts with multiple lanes

📌 Why is this important?¶

Camera mounted too low → further lanes obscured by vehicles closer to the lens.
Such occlusions are difficult for AI to resolve correctly.
The higher mount reduces obstruction problems and increases the field of view.

Quick Reference Table¶

Scenario	Height	Pitch Angle	Notes
Cross-section	4 m	15°–25°	Camera parallel to the road
Road intersection	5–7 m	30°–45°	Camera right next to the intersection
Roundabout	5–7 m	30°–45°	Camera right next to the roundabout

📐 Pitch Angle and Field of View (FOV)¶

Road Cross-section¶

Tilt (Pitch): 15°–25°
Horizontal FOV: 60°–80°
Alignment: Parallel to the road axis – optimal for License Plate Recognition (LPR) and capturing vehicle side profiles.

Intersections¶

Tilt (Pitch): 30°–45° (can be increased to 45°–60° for large interchanges)
Horizontal FOV: 90°–120°
Note: The closer to vertical (Pitch → 90°, i.e., "bird's-eye view"), the better the visibility of traffic movements and the fewer occlusions.

Roundabouts¶

Tilt (Pitch): 60°–90° (optimal: vertical, Pitch ≈ 90°)
Horizontal FOV: 100°–130°
Alignment: Central mounting above the roundabout (if possible) or multiple cameras at entries – each with its own specific angle.

Optimal Camera Framing for Traffic Flow Counting and ALPR¶

An example of correct framing for a road intersection.

An example of correct framing for a road section.

🛣️ Mounting Location¶

One-way road / Cross-section¶

Pole-mounted by the road
Camera parallel to the road axis
Digital cropping available in AITracker if the camera is positioned away from the road

Intersections¶

Mounted on a pole directly at the intersection
Large intersections: 1 camera per entry

Roundabouts¶

Mounted on a pole directly at the roundabout

Correct Camera Frame Examples¶

Intersection or Roundabout Counting¶

An example of correct framing for an intersection.

Sectional Speed Measurement¶

A correctly defined speed-measurement section.

ALPR for Parking Time Measurement¶

A camera mounted inside a vehicle travelling along the road and counting traffic.

🌙 Night Measurement and Weather Conditions¶

Use cameras with IR (Infrared), especially in unlit areas.
Night ALPR requires dedicated optics: a camera with a suitable lens, a narrow-beam 850 nm IR illuminator mounted close to the camera axis, and manually configured exposure.
For moving vehicles, use a manual shutter of at least 1/1000 s, with 1/2000 s as the target. Use black-and-white mode and verify the result with DNR, WDR, and BLC disabled.
Select the focal length and framing so that the plate is viewed close to head-on, reaches approximately 150 pixels in width, and remains within the illuminator's effective range. A higher frame rate or a wide-angle IR lamp cannot replace suitable optics and exposure.
Rain, fog, or dirt on the lens → although the AI is trained on such footage, severe weather conditions can still reduce analysis effectiveness.

⚠️ Common Mounting Errors¶

Error	Consequence
Mounting too low	Occlusions caused by vehicles in the foreground
Incomplete coverage of the intersection/roundabout	Failure to count entries that are outside the frame
Trees in the middle of a roundabout	Interrupted tracking trajectories
"Face-on" camera alignment instead of an angled view	Causes additional occlusions
Frame too narrow or insufficient resolution	Causes AI errors or failure to recognize objects

💡 How Does Night Lighting Work with the Cameras?¶

Scenario	AI Recognition
✅ A visible vehicle silhouette	Ensures AI recognition
✅ A partially visible vehicle silhouette	Sufficient for AI
❌ A vehicle as a ball of light	Will NOT be recognized
❌ Vehicles with only headlights visible	Insufficient for AI
⚠️ High speed and significant blur	Borderline recognizable

🧩 Example Problems and Solutions¶

Problem: "The camera cannot see the second lane; it is obstructed by a truck."¶

✅ Solution: Increase the mounting height or add a second camera.

Problem: "ALPR fails to recognize plates at dusk."¶

✅ Solution: Use a shorter exposure time to reduce motion blur. A higher FPS provides more frames but does not by itself shorten exposure; configure exposure, frame rate, viewing angle, and illumination separately.

Problem: "ALPR fails to recognize plates at night."¶

✅ Solution: Use a dedicated ALPR camera and lens, a narrow-beam 850 nm IR illuminator close to the camera axis, and a manual shutter of at least 1/1000 s, targeting 1/2000 s. Select black-and-white mode, test with DNR/WDR/BLC disabled, and match the beam, power, and focal length to the reading distance. In a test recording, the plate should be sharp, correctly exposed, and approximately 150 pixels wide.

📚 Additional Resources¶

For more details regarding camera mounting, refer to the Hardware Documentation