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