Masking video screens are front projection screens able to accommodate different aspect ratios, based on the specifications of the program material. For instance, 16x9 HDTV broadcasts are more square than the 2:35:1 Cinemascope ratio found on many movies. Masking screens can adjust, usually with retractable felt bars, to change to the needs of the material.
Auto-masking screens are motorized and change to the exact specifications of the material for the specific screen. Nothing says "WOW factor" in a home theater more than an auto-masking screen making its adjustments before a movie or sporting event.