Hard drives for video surveillance

How do I optimize my video storage?

Video surveillance is used because there are things one does not want to miss.
Therefore, the premise is that you'd rather record an hour too much than miss a single second.
On the other hand, recordings take up space, so the more you record - the fewer days of recording you'll have space for.

Fortunately, most high-end recorders and cameras have advanced intelligence that can help you maximize the use of storage space.

Motion Detection

If not even a single pixel moves in the image, there's often no reason to record it.

Therefore, cameras are typically set to only record when motion is detected. This significantly reduces the storage requirement. And most cameras are even so intelligent that they can record, for example, 5 seconds BEFORE motion is detected - ensuring you don’t miss the beginning. It might seem strange that this is possible, but the cameras achieve this by continuously recording and then discarding the footage before it gets stored, unless some subsequent motion is detected.

The storage use is thus influenced by the amount of motion in the area. Often it's minimal, but it can quickly change if, for instance, the camera is pointed towards a flag fluttering or a bush swaying in the wind - which is typically not of interest.

Again, you can adjust the camera settings to make a significant difference. You can mask out the flag, for example, and thereby tell the camera that you're aware of the flag's movement, and that it's not of interest, so the camera can safely ignore it.

With such settings, you can often 5- or 10-fold the number of days you can store on your disk.

Compression Choices

There are many ways to optimize storage use through compression. Some methods compromise the quality of the recordings, so they're not commonly used. When you've purchased a camera with an excellent image and a crisp 4K resolution - you'd obviously want to capture everything. However, you CAN instruct the camera to only save in a lower resolution, or at 8 frames per second instead of the typical 30, or to compress very aggressively.

Use h265

The wise solution for optimizing storage use is the choice of video protocol. A commonly used one is h264, which dates back to 2003. A newer standard is h265, which as the number suggests, is a step up. It has been used in modern streaming services offering 4K content. Typically, with h265, you can halve the storage requirement without compromising on quality.

Variants of h265

h265 was developed with movies in mind. In a film, the camera often moves around, and entire scenes change. In video surveillance, the scene usually remains unchanged. The wall you might see on the left of the picture stays exactly in the same place hour after hour, day after day. Many manufacturers have capitalized on this by introducing their own variants of h265, which they often label h265+, ultra h265, or some other imaginative term. These are protocols where they've tried to optimize h265 compression for the conditions typical in video surveillance, where most of the image often remains static.

Typically, this results in another halving of the storage requirement - though it's often noticeable in the recordings, even if they do a good job of keeping the most important parts of the recordings clear.

Whether one uses these customized versions is a matter of personal preference. Personally, I don't.

The Bottom Line

The difference between recording 24/7 with h264 and recording three hours of daily motion with h265 is the same as the difference between having space for 4 days of recording and having space for two months of recording. Thus, it's unwise not to properly set up your equipment. If it's too complex, you can have one of our experts help configure and fine-tune your system. They can do it online, by sharing your screen while you speak over the phone. We call it Rent a Technician Online.