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Appendix B
Calculate Recording Capacity
Users can calculate the size of hard disk according to the saving time and DVR recording settings. The DVR
uses fixed video bit rate. The below are the details at different settings.
Video
Format
Resolution
Frame Rate
Totally(FPS)
Video Quality
Bit Rate
(kbps)
Used
Space(MB/h)
Highest 1M
465
Higher 768k
297
Medium 512k
230
Low 384k 173
Lower 256k
115
NTSC CIF
30
Lowest 128k
56
Highest 1M
466
Higher 768k
295
Medium 512k
235
Low 384k 175
Lower 256k 56.4
PAL CIF 25
Lowest 128k
45
The calculation format is:
Total Recording capacity =Used space per hour (MB/h)
(coverage rate of hard disk) × recording time
(hour) ×channel numbers
For instance, one customer uses PAL cameras, set resolution to CIF, video quality to Lower, frame rate to 25
fps for enabling total 16 channels. He wants the unit to record continuously in a month. Below is the
calculation:
Total Recoding capacity =56.4 (mb/h) X 24(hours/day) X30(days) X16(channels)= 649728(MB)
≈
650(GB)
Therefore, customers just install two SATA HDDs with 320GB, it can almost record for one month.
