EN 62676-4 DORI · Lens FOV · Per-Camera & Site Overlap
When to use: Use this designer to size a multi-camera CCTV layout. For each camera it computes the lens field of view from FOV = 2·atan(d / 2f), the horizontal coverage width at the working distance, and the resulting pixel density — then classifies it against the EN 62676-4 DORI levels (Detection 25, Observation 62.5, Recognition 125, Identification 250 px/m). The site overlap analysis sums per-camera coverage against the area you need to cover and recommends how many cameras achieve your target DORI level. Real coverage also depends on mounting height, tilt, and obstructions.
Site Parameters
Horizontal span
ft
Cameras (3)
Fixed
mm
MP
To target
ft
Wide
mm
Tele
mm
MP
To target
ft
Panomorph
mm
MP
To target
ft
Primary Camera — Cam 1 — Entry
Fixed · 1/2.8" (5.6×3.2 mm) · 4 MP
70.0°
HFOV
42.0 ft
Coverage @ Dist
208 px/m
Pixel Density
Recognition
DORI Level
Per-Camera Coverage Table
Camera
Type
Focal
HFOV
Coverage @ D
px/ft
px/m
DORI
Cam 1 — Entry
Fixed
4 mm
70.0°
42.0 ft
63
208
Recognition
Cam 2 — Lot
Varifocal
2.8–12 mm (4.3×)
91.6°–27.0°
123.4–28.8 ft
31
100
Observation
Cam 3 — Overview
Fisheye
1.4 mm
~180°
78.5 ft
42
136
Recognition
Varifocal / PTZ show wide→tele range; px/ft, px/m and DORI use the wide (worst-case density) setting. Fisheye uses ~180° panoramic coverage — dewarping divides the imager across the field, reducing effective px density per zone.
Site Overlap Analysis
Site Width to Cover100.0 ft
Total Camera Coverage (sum of widths)244.0 ft
Overlap (sum − site)144.0 ft
Coverage Ratio244%
Per-Camera Width @ Recognition42.0 ft
Recommended Cameras @ Recognition3
✓ Site is covered. Cameras provide 244.0 ft against a 100.0 ft span, leaving 144.0 ft of overlap for handoff redundancy. Note: this sums raw FOV widths and does not account for tilt, mounting height, or blind spots between fields.