Related tools
Estimate DORI distances, calculate field of view, estimate lens focal length, or plan IP camera bandwidth.
How to Calculate Pixels Per Meter
Pixels Per Meter = horizontal resolution divided by scene width in meters. For example, 3840 px divided by 20 m equals 192 px/m.
Can You Convert Meters to Pixels?
There is no fixed meter-to-pixel conversion for CCTV. The answer depends on camera horizontal resolution and the physical width covered by the image.
A 3840-pixel image covering 20 meters gives 192 px/m. The same 3840-pixel image covering 40 meters gives 96 px/m. That is why pixel density changes when the camera view gets wider or narrower.
Pixels Per Meter vs Pixel Density
In CCTV planning, pixels per meter is a practical measure of pixel density across a physical scene. Higher PPM means more image detail per meter, but real usable detail still depends on focus, lighting, motion blur, compression, camera angle and lens quality.
Pixels Per Meter and CCTV DORI
PPM is commonly used to estimate whether a camera view is suitable for Detection, Observation, Recognition or Identification planning. This page explains what the current pixel density means; the DORI Distance Calculator is the deeper tool for planning distances from FOV and resolution.
Common CCTV PPM Examples
| Horizontal Pixels | Scene Width | Pixel Density |
|---|---|---|
| 1920 px | 10 m | 192 px/m |
| 2560 px | 20 m | 128 px/m |
| 3840 px | 20 m | 192 px/m |
| 3840 px | 40 m | 96 px/m |
These examples show why more scene width reduces pixel density even when the camera resolution stays the same.
FAQ
What is pixels per meter in CCTV?
Pixels per meter is horizontal pixel density across a real scene. It tells you how many image pixels cover each meter of scene width.
How do I calculate pixels per meter?
Divide horizontal camera resolution by scene width in meters. For example, 3840 px divided by 20 m equals 192 px/m.
Can I convert meters directly to pixels?
No. There is no fixed meter-to-pixel conversion. You need both horizontal image resolution and the physical scene width covered by the image.
What is pixel density in CCTV?
Pixel density is the amount of image detail across a physical scene. In CCTV planning, PPM is a practical pixel-density measure.
How does camera resolution affect PPM?
Higher horizontal resolution can increase PPM if the scene width stays the same, but megapixels alone do not define pixel density.
How does scene width affect PPM?
Wider scene coverage lowers PPM because the same horizontal pixels are spread across more physical width.
What PPM do I need for CCTV identification?
This page uses 250 px/m as the Identification planning threshold, but real identification also depends on lighting, angle, focus, motion blur, compression and lens quality.
What is the difference between PPM and DORI?
PPM is the pixel-density number. DORI is a planning framework that compares pixel density with Detection, Observation, Recognition and Identification thresholds.
Does a 4K camera always give better PPM?
No. A 4K camera covering a very wide scene may have lower PPM than a lower-resolution camera covering a narrower scene.
Why does PPM decrease when scene width increases?
The same number of horizontal pixels has to cover more meters, so each meter receives fewer pixels.