Most disappointing CCTV systems were specified by camera count. Good systems are specified by what the footage must achieve. Start with that question for every camera position.
Decide the purpose of each view
The international standard for video surveillance systems, IEC 62676-4, describes how detail requirements translate into pixel density, measured in pixels per metre at the target. Commonly used guide values are roughly 25 pixels per metre to detect that something is there, 62 to observe behaviour, 125 to recognise a known person, and 250 to identify an unknown person.
That is why a gate camera for number plates and a camera for a wide yard are specified differently, even if they look the same on a drawing.
Size storage from facts
Storage depends on the number of cameras, resolution, frame rate, compression, how much of the day has motion, and the retention period. Agree the retention requirement first, then calculate. Underestimating storage is the most common reason systems overwrite footage sooner than the owner expects.
Plan the network and power
- Use power over Ethernet and mind cable length limits.
- Put cameras on their own network segment and keep recorders off the open internet.
- Budget switch uplinks for the video traffic, not just the port count.
- Plan for lighting. Low light is the most common cause of poor footage.
Treat cameras as IT devices
Cameras run software, have accounts and sit on your network. Change default credentials, manage firmware, use encrypted connections, restrict who can export footage and log access. A camera network that is not secured can become the way in to everything else.
Analytics where they pay for themselves
Number plate recognition, people counting and perimeter detection are valuable when there is a clear use case and a person who will act on the alerts. Trial them on a few cameras before committing to a site-wide rollout.
Check local rules
Requirements for installers, approved equipment and signage differ across emirates and in Saudi Arabia. In Dubai, for example, the Security Industry Regulatory Agency (SIRA) regulates CCTV. Confirm what applies to your premises before you buy.