Documentation for Axxon PSIM 2.0. Documentation for other versions of Axxon PSIM is available too.

Previous page Next page


Axxon PSIM allows saving the video recordings to the hard drives (maintaining a video recordings archive). Archived information can be saved to the hard drives of such types as SCSI, IDE, SATA, USB, and also RAID arrays. SCSI disks and RAID arrays (in particular RAID 5) allow for accelerated data search and recording.

The size of the disk array determines the length (time-based length) of the saved and archived video recording. The size of the disk array is selected based on the required parameters of the video recording.

Attention!

For the correct operation of video archive recording, the disk space size must exceed the Ring parameter that is specified in the Video Subsystem section of the advanced system settings utility (see The settings panel for the Video subsystem section).

To determine the disk space required for storing archive from IP cameras, please use the online calculator. Documentation on the calculator is available here.

The table below shows the average frame size of a PAL video signal depending on frame resolution, video signal compression, the color grade of the image and frame resolution, frame chromaticity, and the motion level in the frame.

Video card type

Resolution

Color

Frame size (Kb) with 50% of motion in the frame

Frame size (Kb) with 75% of motion in the frame

Frame size (Kb) with 100% of motion in the frame

SC390N16 (WS16)

704x576

color

15

30

61

black-and-white

10

22

42

704x288

color

6

10

30

black-and-white

4

9

18

352x288

color

4

6

17

black-and-white

2

5

10

SC3B0N16 ( WS216)

704x576

color

19

35

101

black-and-white

11

33

65

704x288

color

8

12

49

black-and-white

6

11

29

352x288

color

4

7

25

black-and-white

3

6

15

FX416\MS416

To calculate the required disk space for these cards, please use the online calculator

SL16-200 (FX116)

SC310N16 (FX16)

SC200Q4 (FS15)

SC200Q4 LOW PROFILE (FS115)

SC300Q16 (FX4)

SC300D16 (FX8)

SC230N4

SC330Q16 (analogue of SC300Q16)

SC330D16 (analogue of SC300D16)

 

FS5\FS6\FS8\FS16

704x576

color

26

59

103

black-and-white

24

42

91

704x288

color

17

26

52

black-and-white

16

24

47

352x288

color

11

15

39

black-and-white

10

14

37

Note

The table shows the examples of frames for video cameras with a set frame frequency of 25 FPS.

You must calculate the archive depth, taking into account the resolution and frame compression, image color, video signal frame rate, and the number of cameras from which recording is performed on disk(s) during continuous recording.

You can use the following formula to calculate the archive depth:

Archive depth (days) = (1024 (MB/GB) * 1024 (KB/MB) * Hard drive size (GB)) / (60 (s/min) * 60 (min/hr) * 24 (hr/day) * Frame size (Kb) * Frame rate (frames/s) * Number of cameras)

Comments related to the formula. To estimate the archive depth, you must do the following: divide the size of the hard drive in KB (the rates for converting GB into KB are included in the numerator of the formula) by the frame size, determined from the table based on the video signal parameters, and by the frame rate per camera and the number of cameras connected to the server. Archive depth in this case is measured in seconds. Now, the archive depth expressed in seconds must be converted to the number of days (the rates to convert seconds to days are given in the denominator of the formula).

Note

You can also use a simplified formula to calculate the archive depth in which numerical conversion factors are reduced to a single numerical value:

 Archive depth (days) = 12 (KB/GB * day/s) * Hard drive size (GB) / (Frame size (KB) * Frame rate (frames/s) * Number of cameras)

Example. For example, if the size of a hard drive is 40 GB, four cameras are continuously recording PAL video signals with 10 frames per second and 150 KB frame size. Based on the formula:

Archive depth (days) = 12 (KB/GB * day/s) * 40 (GB) / (150 (KB) * 10 (frames/s) * 4) = 0.08 (days)

The calculation shows that the video archive depth in the particular case is 0.08 days (about 1 hour 55 minutes).

When you calculate, you estimate the frame size based on the table above.

Note

To calculate the size of a hard drive, you must take into account the following specific features:

  • About 5-10% of the hard drive size is taken up by the filing subsystem data.
  • To ensure that Windows OS is operating properly, at least 20% of free disk space is required. By default, system files of the Windows OS are allocated 1000 MB. To change this value, you need to make changes to the Windows registry using the Tweaki.exe utility included in the Axxon PSIM distribution.

The table below shows archive sizes calculated for hard drives of various sizes, based on a continuous incoming PAL video signal recording from one camera with a frame rate of 25 FPS.

Resolution

Hard drive size

80 GB

160 GB

400 GB

750 GB

352x288 b/w

2.1

4.3

10.7

20.0

352 x 288 color

1.9

3.8

9.6

18.0

704x288 b/w

1.6

3.2

8.0

15.0

704 x 288 color

1.5

3.1

7.7

14.4

704x576 b/w

1.2

2,3

5.8

10.9

704 x 576 color

1.1

2,3

5.6

10.6

  • No labels