Know The Difference
Everyone knows that DVRs and NVRs are responsible for video recording, but getting a clear understanding about the differences between the two is essential when evaluating security systems.
Digital Video Recorder- DVR
DVRs generally offer what is known as “D1” resolution. This is the traditional video quality used in closed-circuit television systems. D1 equates to a resolution of 720×480 pixels, which is considered a “standard resolution” that can be recorded and, hence, displayed on a playback monitor.
DVR encodes the video signal at the DVR, not at the camera, and is limited by the number of cameras and distance between cameras and the DVR.
DVRs must be hardwired directly to a limited number of cameras. Connecting analog cameras with a DVR system is done by directly plugging a BNC coaxial cable from the DVR into the camera. To connect more cameras to the DVR system, you need additional coaxial cables. Such systems are difficult to expand because once every BNC connection on the DVR unit is occupied by a camera, you’ll need to purchase an entirely new DVR before adding another camera to the system. (DVRs are typically sold with four, eight or 16-camera input capabilities.) DVRs also require that the connected cameras be installed within approximately 500 feet of the DVR, otherwise the video quality begins to degrade and may require a video signal amplifier. Finally, DVRs may not provide power through the cable connections to the attached cameras, thereby requiring you to install additional equipment for supplying power to your cameras.
Network Video Recorder- NVR
NVRs can record in 8K, which is high-definition (HD). For comparison purposes, 8K equates to a pixel resolution of 7,680 horizontal and 4,320 vertical pixels lines when viewed on a monitor. This results in a much clearer, cleaner recorded video image.
NVR setups use a software program to record — it’s basically a computer connected to the internet. They can be installed anywhere on the internet and be programmed to sync with the assigned cameras.
NVR systems connects directly to a network. IP cameras that are connected to the same network, usually by a PoE switch, are then able to transmit footage to the NVR. Using PoE, or “Power over Ethernet,” means the electric required for the camera runs through the same Ethernet cable that carries the computerized video information. Thus, NVR setups are much easier to scale up than DVR systems, simply because they can accept any new camera added to the network with nothing more than something like an additional PoE switch, if that. Some IP cameras also transmit footage to the NVR over Wi-Fi. There are no proximity limitations to these arrangements so long as a camera is connected to the same network as the NVR.
In conclusion, the sole difference between DVRs and NVRs is how they process video data.
*It is important to note that a DVR based system is a wired security system, whereas NVR systems can be wired or wireless.
*DVR systems process the video data at the recorder, whereas NVR systems encode and process the video data at the camera, then stream it to the NVR recorder which is used for storage and remote viewing. Are you processing this yet?
*As DVRs and NVRs handle the video data differently, they require different types of cameras. NVRs are used with IP cameras whereas DVRs are used with analog. Remember, not every IP camera will work with every NVR, so, you’ll need to know whether your cameras will be compatible with a given video recorder before investing. Contact a Consultant
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