How much footage can my CCTV DVR hold?

One of the most important things to consider when purchasing a complete CCTV system– and one of the most overlooked- is the question of how much storage you need for your recorder. Just like a computer, most CCTV DVRs are fitted with Hard Disk Drives (HDDs) to which they record your security footage. Our recorders all ship with at least a 500GB HDD, but for many scenarios this will simply not be enough, and it pays to expand this storage using our simple upgrade menus. But how much is enough?

For most, it’s simply as much as you can budget for, but in some situations this is dictated by the CCTV’s use. Bars & Clubs for example, are mandated to store at least 30 days worth of footage in order to comply with the terms of their alcohol licence. Figuring out how much hard drive space you need for a specific amount of footage is actually a rather complex thing, as it relies on 4 different factors:

• Number of Cameras– For each camera you have, the recorder has to store another stream of information, so doubling the number of cameras will halve the recording time
• Recording Resolution– You can increase recording time by dropping the resolution of your recordings, but we do not recommend setting this to less than D1 quality (720×576), as this will impact the detail captured in the footage
• Recording Quality– In addition to the resolution, most DVRs will let you drop the quality (or bitrate) of the footage, impacting the colours clarity of the video. Generally speaking, it is better to adjust this as opposed to the resolution
• Frame Rate– Many DVRs are capable of recording smooth video at 25fps (frames per second), similar to a TV. This is usually the best thing to adjust if you want to increase your recording time, as you can drop it right down to 6fps and have footage that looks a bit jerky, but still captures plenty of detail. Halving this frame rate will double your recording time.

As you can see, the actual recording time can be affected by many different settings, so we do not generally advertise kits as recording for a certain number of days. However, to help give an idea of what you can expect from some typical combinations, we have drawn together this quick table of examples. For each of these, we have given recording times for a DVR set to D1 resolution and standard quality recording.

One final thing to mention, the above recording times are for 24/7 continuous monitoring. In many cases- especially for recorders used on properties after hours-  the recorder will be set on motion detection. This means it will only start recording when there is movement in front of a camera to trigger it. As a result, the total time that you can leave the system running will be quite a bit longer than the recording time above.