QSDT8DP DVR User’s Manual
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Appendix B
Calculating Recording Capacity
Users can calculate the size of hard drive needed based on DVR recording
settings. The DVR uses fixed video bit rate. Below is the space used at
different settings.
Video
Format
Resolution
Frame
Rate
Total
(FPS)
Video Quality
Bit Rate
(kbps)
Storage
Used
(MB/h)
PAL
CIF
25
Highest
640
281
Higher
512
225
Medium
384
168.7
Lower
256
112.5
Lowest
128
56
NTSC
CIF
30
Highest
640
281
Higher
512
225
Medium
384
168.7
Lower
256
112.5
Lowest
128
56
For example, if a customer uses NTSC cameras, sets resolution to CIF,
video quality to Lower, frame rate to 240fps for 8ch total, and he wants the
unit to continuously record for a month, below is the calculation:
Storage used in a day: 112.5X24(h)X(240fps/30fps)
≈
21GB
Storage used in 30 days: 21X30
≈
630GB
So the customer must install SATA HDDs with 630GB capacity for it to
record a month.