A: Before calcuate storage space, you must understand what is CBR first.

When set up the configuration of camera, you will see the bit rate as below:

CBR means you can fix the bitrate by the value you chose.

There are many bitrate values you can choose and this value is the most important element to calcuate storage space.

If you choose VBR(Variable Bit rate), you can't calculate the storage capacity, because the bit rate is variable. Thus, before you calculate storage capacity, you have to decide which CBR value you want to use.

For example:
 I have 5 cameras, CBR=1.5Mbps and I need recording 10 days. How much capacity I need?

First, you have to change the unit from bit to byte. 1 byte = 8 bit.
1.5Mbps(bit per second), 1.5M bit / 8 = 0.1875M byte / per second

0.1875 x 60 seconds = 11.25Mbyte / per minute
11.25 x 60 minutes   = 675Mbyte / per hour
675 x 24 hours = 16200Mbyte / per day

1GB = 1024MB
1TB = 1024GB

16200Mbyte / 1024 = 15.8GB / per day per camera.
15.8 x 10 days x 5 camera = 790GB