Audio/Video Glossary - Noise ReductionAn electronic process used to reduce noise* level in audio and video. It can be performed either before or after recording. An encoding/decoding system, such as the Dolby* noise reduction system, is used before recording. Noise reduction can be performed on an existing tape using DNR (dynamic noise reduction). In professional video production, the most effective means of noise reduction is by digitizing the video image and carrying out a computerized pixel by pixel analysis of the data. In this way most of the noise elements can be discarded.