Number of cameras
The number of cameras to be used.

Average image Size (kB)
The number of (images) (frames per second or FPS) from each camera.

Typical image sizes are:
352x288 medium-high compression: 8 kB
352x288 medium-low compression: 15 kB
640x480 medium-low compression: 50 kB
640x480 lowest compression: 375 kB

The image size will vary according to lighting conditions and the actual content.
For this reason an overhead of at least 10% is recommended.

Image Rate
The number of frames (images) per second [FPS] from each camera.

Days to Store
The number of days to store the recordings. If storing of several days is required, or 3rd party backup software is to be used, the Archiving functionality should be used. When using the Archiving functionality, the number of days to archive plus one (the current day) should be entered.

Be aware that if the remote archiving (i.e. archiving on a network drive) functionality is used, the local HDD size should be able to store approximately double the size of the daily databases. Thus 2 should be entered when calculating the local drive requirements, whereas only the actual number of days to archive should be entered when calculating the remote drive requirements.

Hours recording per day
The number of hours the camera is online per day (as set in the Scheduler).

Percentage of time with motion
The expected maximum percentage of movement recorded, if only images with motion are to be stored in the database.
If all images are chosen to be stored in the database, 100 should be entered.