Video Recording and Storage Flashcards

What does the term 'compression ratio' refer to in video storage?

Answer: The ratio of original file size to compressed file size

Compression ratio describes how much the original video data has been reduced in size after encoding.

Which RAID level provides disk striping with parity, requiring a minimum of 3 drives?

Answer: RAID 5

RAID 5 uses block-level striping with distributed parity data across at least 3 drives, allowing one drive failure without data loss.

In NVR systems, what primarily determines the maximum number of cameras supported?

Answer: Processing power and licensed channel count

NVR channel capacity is limited by its processing power for decoding streams and the number of licensed channels.

What is 'continuous recording' mode in a DVR/NVR?

Answer: Recording around the clock regardless of activity

Continuous recording captures video 24 hours a day, 7 days a week without gaps.

Which video codec is most commonly used in modern IP camera systems for efficient compression?

Answer: H.264

H.264 (AVC) is the industry standard for IP camera systems due to its excellent compression efficiency and broad hardware support.

What happens to recorded footage when a DVR's hard drive reaches full capacity in overwrite mode?

Answer: The oldest footage is automatically deleted to make room

In overwrite mode, the DVR automatically deletes the oldest recorded footage to free space for new recordings.

What is the purpose of a video management system (VMS) in a CCTV installation?

Answer: To centrally manage recording, playback, and camera configuration

A VMS provides centralized software for managing camera feeds, recording schedules, playback, and system configuration.