Video Surveillance System Design Flashcards

What is the key advantage of using PTZ (Pan-Tilt-Zoom) cameras in a surveillance system design?

Answer: They can cover a large area and zoom in on incidents under operator control or via automation

PTZ cameras provide flexible, wide-area coverage with the ability to zoom in on specific incidents, making them ideal for large open areas with active monitoring.

In a risk-based CCTV design approach, which area would typically be classified as 'high risk' requiring the most camera coverage?

Answer: A loading dock with high-value goods and frequent external access

Loading docks combine high-value assets, external personnel access, and limited supervision, making them high-risk zones that require intensive camera coverage.

What does 'pixels per foot' (PPF) or 'pixels per meter' measurement determine in CCTV design?

Answer: The image detail available for a given subject size, determining if identification is possible

PPF/PPM defines how much image detail is available for a target at a given distance, directly determining whether the system can detect, recognize, or identify a person.

When a designer specifies 'detection' level coverage versus 'identification' level coverage, what is the main difference?

Answer: Detection confirms presence of a person; identification captures enough detail to recognize who the person is

Detection verifies that a person or object is present in an area, while identification requires sufficient image resolution to distinguish specific facial or physical features.

What redundancy measure is commonly designed into critical CCTV systems to prevent total recording loss during a power outage?

Answer: Uninterruptible Power Supplies (UPS) and/or backup generators

UPS units provide immediate battery backup during power interruptions, while generators ensure long-term operation, preventing gaps in critical surveillance recording.

Which network topology is most commonly used in IP-based CCTV system design to connect cameras to an NVR or VMS server?

Answer: Star topology using network switches

Star topology connects each IP camera to a central network switch, which then connects to the NVR/VMS, providing easy troubleshooting, scalability, and isolation of faults.

What is the purpose of conducting a 'camera coverage audit' after a CCTV system is installed?

Answer: To confirm actual camera views match the designed coverage plan and identify any remaining blind spots

A post-installation coverage audit validates that each camera achieves its intended field of view, image quality, and coverage overlap as specified in the design documentation.