Calculator Inputs
This tool supports surveillance planning for cybersecurity-driven physical security reviews, camera audits, and site hardening assessments.
Example Data Table
| Scenario | Site Size | Height | FOV | Tilt | Resolution | Far Width | Far PPM | Estimated Cameras |
|---|---|---|---|---|---|---|---|---|
| Small Office Entrance | 12 m × 18 m | 3.0 m | 92° × 58° | 38° | 3840 × 2160 | 39.23 m | 97.89 | 2 |
| Retail Aisle Monitoring | 8 m × 25 m | 3.5 m | 80° × 50° | 32° | 3840 × 2160 | 47.84 m | 80.27 | 2 |
| Warehouse Gate | 16 m × 30 m | 5.0 m | 70° × 42° | 28° | 2688 × 1520 | 49.01 m | 54.84 | 2 |
Formula Used
1. Near distance: Near Distance = Mounting Height ÷ tan(Tilt + Vertical FOV ÷ 2)
2. Far distance: Far Distance = Mounting Height ÷ tan(Tilt - Vertical FOV ÷ 2)
3. Width at any distance: Width = 2 × Distance × tan(Horizontal FOV ÷ 2)
4. Coverage depth: Coverage Depth = Far Distance - Near Distance
5. Ground area: Area = ((Near Width + Far Width) ÷ 2) × Coverage Depth
6. Pixel density: PPM = Resolution Width ÷ Scene Width
7. Effective area: Effective Area = Coverage Area × (1 - Overlap %)
8. Camera estimate: Cameras = ceil(Site Width ÷ Effective Width) × ceil(Site Length ÷ Effective Depth)
These formulas are practical planning estimates. Real installations still need site tests, lens checks, compression review, lighting review, and obstruction review.
How to Use This Calculator
- Enter the site width and site length in meters.
- Set the planned camera mounting height.
- Enter lens horizontal and vertical field of view values.
- Provide the downward tilt angle below horizontal.
- Set the maximum distance you want analyzed.
- Add camera resolution and your required pixels per meter.
- Enter planned overlap between adjacent camera views.
- Press Calculate Coverage to show results above the form.
- Review the chart, far-edge detail, and estimated camera count.
- Download the summary as CSV or PDF if needed.
FAQs
1. What does pixels per meter mean?
Pixels per meter shows how much image detail exists across one meter of scene width. Higher values support stronger recognition and identification results.
2. Why does far-edge detail matter most?
Far-edge detail is usually the weakest part of the scene. If it fails your threshold, the camera may miss usable evidence where subjects appear smallest.
3. Does a wider lens always improve coverage?
No. A wider lens covers more area, but it lowers pixel density. That tradeoff can reduce recognition quality at longer distances.
4. Why is overlap included?
Overlap helps reduce blind spots between adjacent cameras. It also supports smoother tracking when subjects move from one camera zone into another.
5. What creates a blind zone?
The blind zone is the uncovered area nearest the camera. It grows when the camera is mounted higher or tilted more sharply downward.
6. Can this calculator replace a site survey?
No. It supports planning, but it cannot model every obstacle, lighting change, weather effect, or compression setting found on real sites.
7. Which threshold should I use?
Use a threshold based on your objective. Observation needs less detail. Recognition needs more. Identification needs the strongest image detail.
8. Why is this useful in cybersecurity work?
Cybersecurity teams often review physical controls too. Camera coverage, evidence quality, and monitoring gaps directly affect incident response and facility risk.