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 does the term 'latency' refer to in the context of IP surveillance systems?
Answer: The delay between image capture and display on the monitor
Latency is the delay between when a camera captures an image and when it is displayed on a monitor, which is critical in real-time surveillance applications.
Which IP camera feature allows it to operate without a separate power supply by receiving power through the network cable?
Answer: Power over Ethernet (PoE)
Power over Ethernet (PoE) delivers electrical power to IP cameras through the same Ethernet cable used for data, eliminating the need for separate power supplies.
A surveillance camera is installed facing a window with bright outdoor light, causing subjects indoors to appear as silhouettes. Which camera feature would best correct this?
Answer: Wide Dynamic Range (WDR)
Wide Dynamic Range (WDR) technology allows a camera to capture detail in both bright and dark areas of the same frame, correcting silhouetting caused by backlighting.
What is the primary function of an analog-to-digital encoder (video encoder) in a surveillance system?
Answer: Convert analog camera signals into digital IP streams for network transmission
A video encoder converts analog camera signals into digital IP streams, allowing legacy analog cameras to integrate into modern IP-based surveillance networks.
Which audio surveillance microphone type is most directional and best suited for picking up sound from a specific distant source?
Answer: Shotgun microphone
A shotgun microphone has a very narrow pickup pattern (supercardioid or hypercardioid) and is highly directional, making it ideal for capturing sound from a specific distant source.
What is the purpose of a dewarping algorithm in a fisheye surveillance camera system?
Answer: Correct the barrel distortion in fisheye images to produce normal-looking video
Dewarping algorithms mathematically correct the barrel distortion inherent in fisheye lenses, converting the circular fisheye image into standard rectilinear views.
In surveillance systems, what does ONVIF stand for and what is its primary purpose?
Answer: Open Network Video Interface Forum; standardizes interoperability between IP-based security products
ONVIF (Open Network Video Interface Forum) is an industry standard that ensures interoperability between IP-based security products from different manufacturers.