What is DNR (Dynamic Noise Reduction)?

DNR is the process of removing ‘noise’ (signal distortion) from dynamic or time-varying signals such as audio or video signals. Noise is a by-product of amplifiers used to boost a weaker input signal. This happens in both analog CCTV cameras and digital/IP cameras since all use some signal gain software in their internal digital signal processor hardware, and is particularly present in low light video.

Video noise can present itself in many forms like static, fog, transparent blocks on the screen, little specks that look like snow—or a number or other visual artifacts that lower the video quality. This is why being able to employ Dynamic Noise Reduction is important to achieve a clear image, especially in low light situations with long-range lenses.