Flesh Tone Noise Reduction Correction is used in vedeo processing to create a natural look to human skin. Noise Reduction is an essential part of video processing devices. However, spatial filters may cause smoothing or removing of small details, softening or blurring the image. This is especially visible when video has flesh tones (human faces, or any fragment of human skin). It creates a perception that human skin looks artificial.
To mitigate this artifact, a flesh tone detector is utilized. For pixels where flesh tone is not detected, a stronger spatial noise filtering is applied. For pixels where flesh tone is detected, a weaker filtering or no filtering is applied.
The flesh tone detector detects skin based on the luma and chroma components of each pixel. Despite the fact that there is a big variety of human skin colors, they still occupy a reasonably small range of the RGB color space.