In order to understand the benefits of digital noise reduction (DNR) technology, we first have to understand “noise”. Noise is any unwanted disturbance in a signal. It can block, distort, change or interfere with the signal.
In signal processing it is any unwanted data that is produced as an unwanted by-product of other activities and is not used to transmit the signal. In video signals this comes across as fine static or “snow”.
For example, you are having a conversation with a friend in a crowded restaurant. Your conversation is the signal, or the message you want your friend to hear. Any other noise you hear at the restaurant such as music or other conversations going on around you are noise.
Like your brain filters out unwanted background noise to receive your conversation, DNR filters out any unwanted data and corrects any imperfections in the video signal.
Benefits of DNR
Digital noise reduction in action
There are several benefits to digital noise reduction (DNR). These include:
- A cleaner signal
- A more visually appealing image
- The ability to better distinguish between true motion and image noise
First, DNR delivers a cleaner signal, resulting in up to 70% disk space savings – so you can store more video evidence on your hard drive.
Next, cameras equipped with DNR technology deliver a more visually appealing image, making it easier to identify suspects.
Finally, DNR technology makes it easier for your camera to distinguish between true motion and image noise – allowing for your DVR to be more efficient in motion detection – especially in low light conditions.
How DNR Works
The chip in your camera is constantly picking up noise (fine static) in your images, especially in low-light modes. DNR technology compensates for this, correcting imperfections in the image by removing a large percentage of this noise.
When your DVR or computer is processing the video data, it must compress and save every part of the image that is moving. The less noise in your image, the less data that your DVR will save, and the more real motion your DVR will detect.