Security digital video recording devices are an integral part of every video security system. They are used to receive and store signal from security cameras, and today they offer a range of additional features that gives them better functionality. That being said, there are some things you need to make sure your DVR covers before going to the advanced features.
The first thing you need to look for in a DVR is the right number of channels. Each camera you have will need to have a separate channel, so if you’re planning to have four cameras installed, don’t go for a single channel DVR. If you can’t find a DVR with the exact number of channels you need, it’s always better to choose a model with more channels than installing one camera less. Also, you might want to plan ahead and buy a model with additional channels any way – you don’t know if you’ll need to upgrade your security system and install additional cameras.
When it comes to audio channels, some DVRs have them and are able to record audio as well as video. The audio can be recorded either from a dedicated microphone, or from a microphone installed in the camera. You should know however that covert audio recording may be illegal in your state, and if it is, finding a cheaper model without audio capabilities can save you some money.
The next thing you need to take into account is compression rate. The footage from your cameras need to be compressed in order to take up as little space as possible, and the better the compression rate, the more footage your DVR will be able to record and store.
You will also need to check whether your DVR has enough storage space for your needs. It can be a bit hard to estimate the storage capacities your DVR will need to have because it depends on a lot of factors. But if you only have one or two cameras and you don’t need to keep the footage for a long time, you can have a DVR with a smaller storage capacity. You might find the possibility of unloading data – in this case, video – on an external storage device useful, so you should look for a DVR that has a USB port which can be used to connect a flash drive or an external hard drive to it and transfer data.
The frame rate of at which your DVR records video is also an important factor. Manufacturers usually declare the frame rate for the whole DVR, which then needs to be divided by the number of channels that are used, for example, a 120 fps DVR with 4 channels can record all for channels at 30 fps, or three of them at 40 fps, or 2 of them at 60 fps. You get the idea. Also, a higher frame rate video takes up more storage space than a lower frame rate video, which is another thing you need to factor in.