Appendix Ahdd Capacity Calculation - LJD Digital Security Colossus Pro 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 every hour, unit Mbyte.
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).
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User Manual for COLOSSUS Series Embedded Net DVR
= ÷ ×
8 3600
q d
i i
In the formula:
d
×
=
m q h
i 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
q
T
In the formula: means total number of channels in one DVR
c
q
T
In the formula：a% means alarm occurrence rate
that is the capacity of each
q
i
÷
1024
means the bit rate, unit Kbit/s
i
×
D
i i
c
∑
=
m
i
=
1
i
c
∑
=
×a%
m
i
=
1
i
(1)
(2)
that is needed for
q
T
(3)
that is needed for
q
T
(4)
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