Digital Noise Reduction (DNR) in Video Surveillance

Digital Noise Reduction (DNR) in Video Surveillance

When you finally make the decision to get a security camera for yourself, one important accessory you need to have is the Digital Noise Reduction (DNR). While the name might have you thinking about the noise generated by the area covered by the security camera, it totally has nothing to do with actual noise or sounds. When speaking of noise in video surveillance, we are referring to image noise.

While the concept of image noise might sound strange to regular people, it is what we have seen or experienced at some point in our life. Image noise are distortions which may appear on the video being captured by the camera. These distortions might appear blurry, grainy or with a lot of speckles while the recording is being played. A clear example is experienced when you watch TV with a weak signal. This same experience is similar to image noise in video surveillance.

As you can confirm, watching a recording with image noise is usually unclear and can make it difficult to see the details of the camera recording clearly. In a bid to minimize or eliminate image noise from the recording, it is necessary to apply digital noise reduction techniques in video surveillance.

Why Is This Important?

As noted earlier, the major purpose of using the digital noise reduction techniques is to allow for a clearer and detailed video surveillance. It can be quite frustrating to monitor an area through a blurry and speckle-filled video. With a much clearer footage, the monitoring activity will be quite easy and much more efficient as everything will be seen clearly without having to strain your eyes. In the case where a robbery is staged in your house or property, it is imperative that you have a high quality and clear footage for evidence and proper investigation into the occurrence.

One other advantage of using a digital noise reduction technique for your surveillance system is that it makes your video recording much smaller, which leaves more space for storage. Video recordings with lots of image noise will clearly have a larger file size due to the additional speckles and spots scattered all over the image. Eliminating image noise through the digital noise reduction technique means images have lesser sizes due to the absence of these disruptions and speckles on the footage. Since most video recorder have a limit as to what size of files they can save altogether, using the DNR will obviously help you in conserving your storage space for more recordings.

Types of DNR

Advancing technology have allowed the tech industry to grow in flexibility by providing  variety of products that do the same job but with different features and means. Today, we have 3 types of Digital Noise reduction methods which users of security cameras can employ for a much better recording quality and surveillance. Each of these methods have advantages and offer feature that are unique to them.

2D DNR/Temporal Noise Reduction

2D DNR is the simplest method of digital noise reduction (DNR) today. It works to remove distortions and speckles on your footage by comparing each pixel on every frame and will remove any pixel that does not appear on every frame since these pixels will be detected as image noise. This method is effective and best suited for lower resolution images. However, one disadvantage of using this method is that it will blur or leave “fading trails” on movement.

3D DNR/Spatial Noise Reduction

3D DNR is similar to 2D DNR but offers more. While it also compares each pixel on frames of your footage, it also uses an algorithm to see which pixels change or move to identify which pixels represent image noise. Compared to 2D DNR, this technique is more efficient in eliminating the grainy appearance that occurs on images that were taken in low-light and it doesn’t blur motion.

2D & 3D DNR Combined

Some cameras are capable of combining 2D DNR and 3D DNR for clear footage with minimal image noise. By combining these two, each method’s shortfalls are made up by the other’s strengths. Doing this allows you to take advantage of 2D DNR’s efficiency and 3D DNR’s ability to work on motion in order to get the best result. This method is clearly the most effective considering the fact that it uses the strengths of the two other DNR techniques while eliminating the shortfalls of both. This makes it the most efficient technique to employ for CCTV surveillance system today.


The importance of the Digital Noise Reduction techniques cannot be overemphasized as it provides advantages that allows surveillance activity to be perfect and effective. Without a clear footage, it would be a stretch in the process of recognizing parties which gained access to your property, parties that engaged in robbery in your home or property, or surveillance on a general note.

At www.Servo.ng, our top quality cameras come with DVR technology which allows for a much clearer picture to ensure the efficiency of your surveillance system. Without a doubt, we provide you with the latest technology both in terms of camera, video recorders, and other CCTV accessories that will help you have your work cut out for you. With different deals and promos in place, you can always get the best surveillance technologies for subsidized price. Visit www.Servo.ng today, and you will be glad you did.