Calculating errors are common when estimating surveillance storage (or bandwidth) needed. The most common way to do so is to use an online calculator tool yet these tools are fundamentally insufficient to reflect the particular conditions of various real world deployments. In this report, we explain the key hidden issues and best approach to accurately calculate surveillance storage needed.
Despite the issues, most people use calculators. The big plus is that they are fairly simple to use. Plug in a few basics (number of cameras, resolution, frame rate, etc.) and an estimate is immediately generated. From an IPVM Member's survey, here is the breakdown on preferred method:
However, it is intrinsically impossible for calculators to reflect the range of different conditions cameras are placed in and the variances among camera models. In another IPVM survey, notice the range bandwidth estimates are, even with a set resolution, frame rate and CODEC:
All of the respondents are 'right' even though the answers vary by more than 300%. Differences in cameras used and sites deployed can easily result in massive differences in actual bandwidth / storage consumed. Calculators do not reflect them.
Testing and Research
Over the past year, we have done a series of tests and research reports to examine the fundamentals behind this:
Inside the PRO section, we pull all of this together into a single tutorial.