Video and Audio Surveillance Technology Flashcards
7 cards from real CST practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Video and Audio Surveillance Technology flashcards as text
What is the key difference between a DVR and an NVR in surveillance systems?
Answer: DVRs process analog camera signals while NVRs record from IP cameras over a network
A DVR (Digital Video Recorder) processes and records analog camera signals, while an NVR (Network Video Recorder) receives and stores pre-encoded digital streams from IP cameras over a network.
Which video compression codec offers approximately 50% better compression efficiency than H.264 at the same video quality?
Answer: H.265 (HEVC)
H.265 (HEVC) provides approximately 50% better compression efficiency than H.264, significantly reducing storage and bandwidth requirements while maintaining the same video quality.
A CST is designing an outdoor surveillance system that must operate in temperatures ranging from -40°F to 140°F. Which camera specification addresses this requirement?
Answer: Operating temperature range
The operating temperature range specification indicates the environmental temperatures within which a camera is designed to function reliably.
What does a camera's signal-to-noise ratio (SNR) indicate about its performance?
Answer: The balance between useful video signal and unwanted electronic noise, with higher values indicating cleaner images
Signal-to-noise ratio (SNR) measures the ratio of useful video signal to electronic noise; a higher SNR (e.g., 50dB vs. 40dB) indicates a cleaner, less grainy image, especially in low-light conditions.
In audio surveillance, what is the legal requirement in most US two-party consent states regarding covert audio recording?
Answer: All parties to a conversation must be notified and consent to being recorded
In US two-party (all-party) consent states, all parties to a private conversation must consent to being recorded, making covert audio surveillance potentially illegal without all parties' knowledge.
What is the purpose of video analytics' 'virtual tripwire' or 'line crossing' function?
Answer: Trigger an alert when a person or object crosses a defined virtual line in the video
Virtual tripwire or line crossing detection triggers an alert when a person or object crosses a user-defined virtual line in the camera's field of view, enabling perimeter intrusion detection.
Which type of camera mount allows horizontal and vertical adjustment but locks the camera in a fixed position after installation?
Answer: Fixed wall bracket
A fixed wall bracket allows adjustment of camera direction during installation but locks in position, unlike PTZ mounts which allow dynamic movement after installation.