Adobe After Effects CS3 - Manual (Page 393)

AFTER EFFECTS CS3
User Guide
388
Histogram for image that does not use full tonal range
Input sliders moved so that output uses full tonal range
Histogram showing highlight clipping
Histogram showing shadow clipping
Auto Color and Auto Contrast effects
The Auto Color effect adjusts the contrast and color of an image after analyzing the shadows, midtones, and
highlights of the image. The Auto Contrast effect adjusts the overall contrast and mixture of colors. Each effect maps
the lightest and darkest pixels in the image to white and black, and then redistributes the intermediate pixels. The
result is that highlights appear lighter and shadows appear darker.
Because Auto Contrast and Auto Color don’t adjust channels individually, they don’t introduce or remove color casts.