Autocontrast
The Autocontrast command adjusts the overall contrast and mixture of colors in an RGB image automatically. When identifying the lightest and darkest pixels in an image, Autocontrast clips the white and black pixels by 0.5% - that is, it ignores the first 0.5% of either extreme. This ensures that white and black values are based on representative rather than extreme pixel values.
In the figures below you can see the video picture before and after applying the Autocontrast effect:
Before applying the Autocontrast effect
After applying the Autocontrast effect