Evolveo DETECTIVE S4CIH7D, Руководство пользователя

Страница: 75 / 76

- 155 -
Appendix 3. Hard disk capability calculation
Verify the following when installing the hard drive in the DVR for the first
time:
Hard disk capacity
There is no limit for recording machine. We recommend 120G~ 250G sizes to
keep better stability.
Overall capacity option
The hard disk capacity formula is:
Overall capacity
（
M
）
= channel number*time
（
hour
）
*capacity in an hour
（
M/hour
）
The recording time formula is:
Recording time
（
hour
）
=
overall capacity
（
M
）
Capacity in an hour
（
M/hour
）
*channel number
The DVR introduces the H.264 compression technology. Its dynamic range is
very large so the hard disk capacity calculation is based on the estimation values
of each channel creating files in an hour.
Example:
For one 500G HDD, real time CIF for recording, it will keep recording for about
25 days. HDD spaces per channel are 200M/H, if 4channels real time CIF at
24hours recording uninterrupted, it can last: 500G/(200M/H*24H*4ch) = 26 days.