In contact with customers, or prospective customers, hard drive capacity questions are most common ones. To that effect, I prepared two tools: one being PDF file with various bit rates, days, and hard drive spaces, and other being this little calculator that you can use on-line to help yourself see what hard drive you need.
One comment though: manufacturers of hard drives usualy have 1000 where should be 1024. That means that 1G is 1.000.000.000 bytes for the manufacturer, and in reality it is 1.073.741.824 bytes. So, after making a calculation with tool below, please add 7.3% to the hard drive space calculated.
Please note: you should enter all values EXCEPT the one marked with radio button. That values will be calculated when you press ‘calculate’ button.
Here is the table: hard-disk-bitrate
Calculator below can be used to calculate all combinations of values – for example, if you have fixed hard drive space, and fixed days that you need to record, you can use it to estimate bitrate you should use. Just click on the radio button left of bitrate field, and fill all of the remaining fields. On the other hand, if you need to fix your bitrate, and you have disks of fixed capacity, and want to see how many days of recording that will come to, just click on radio button left of days field, fill in rest of the stuff and click calculate.
When experimenting with various drives/bitrates/days etc. you can make yourself a table of values for comparation. Any time you want you can press ‘add’ button and small table will appear at the bottom of the calculator summarizing your choices.
If still are not sure how to use it, click here to see short movie of it’s usage.