Appendix B: Hdd Capacity Calculation - Q-See QSD42908 Net User Manual

Appendix B: HDD Capacity Calculation

To calculate total capacity needed by each DVR according to video recording (video recording
type and video file storage time).
Step 1: Use Formula (1) to calculate storage capacity
needed for every hour: unit Mbyte.
.
Step 2: After video time requirement is confirmed, according to Formula (2) to calculate the
m
storage capacity , which is storage of each channel needed unit Mbyte.
i
h
Represents the recording time for each day (hour)
i
D
Represents number of days for which the video shall be kept
i
Step 3: Use Formula (3) to calculate total capacity (accumulation)
channels in the DVR during scheduled video recording.
Step 4: Use Formula (4) to calculate total capacity (accumulation)
channels in DVR during alarm video recording (including motion detection).
QSD42908 User's Manual
= ¸ ´
q d 8 3600
i i
d
In the formula: means the bit rate, unit Kbit/s
i
× ×
m q h
=
i i i
In the formula:
å
=
q
T
c
In the formula: represents total number of channels in one DVR
=
q
T
In the formula：a% means alarm occurrence rate
92
q
that is the capacity of each channel
i
¸
1024
D
i
q
T
c
m
i
=
i 1
q
c
å
×a%
m
i
=
i 1
(1)
(2)
that is needed for all
(3)
that is needed for all
T
(4)