Appendix A Hdd Capacity Calculation - Jaycar Electronics N56 Series User Manual

Appendix A HDD Capacity Calculation

Calculate total capacity needed by each DVR according to video recording (video recording type
and video file storage time).
Step 1: According to Formula (1) to calculate storage capacity
channel needed for each hour, unit Mbyte.
In the formula:
Step 2: After video time requirement is confirmed, according to Formula (2) to calculate the
storage capacity , which is storage of each channel needed unit Mbyte.
m
i
Step 3: According to Formula (3) to calculate total capacity (accumulation)
all channels in the DVR during scheduled video recording.
Step 4: According to Formula (4) to calculate total capacity (accumulation)
all channels in DVR during alarm video recording (including motion detection).
means the bit rate, unit Kbit/s
d
i
In the formula:
means the recording time for each day (hour)
h
i
means number of days for which the video shall be kept
D
i
In the formula: means total number of channels in one DVR
c
In the formula：a% means alarm occurrence rate
that is the capacity of each
q
i
= ÷ × ÷
q d 8 3600 1024
i i
= × ×
m q h D
i i i i
c
∑
=
q m
T i
=
i 1
c
∑
=
×a%
q m
T i
=
i 1
(1)
(2)
that is needed for
q
T
(3)
that is needed for
q
T
(4)
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