The method used for storing wide screen movies on DVDs to maximize the resolution on wide screen TVs as well as standard TVs that support anamorphic mode. Similar to the way an anamorphic lens squeezes a wide screen movie horizontally onto a 35mm frame, an anamorphic DVD stretches vertically a 16:9 image frame to fully fill the 4:3 aspect ratio of a standard TV screen. TVs that support anamorphic mode squeeze the image vertically to restore objects to their proper shapes.|
Enhanced for Wide Screen
Labels on DVD cases that say "Enhanced for Wide screen TV" or "Enhanced for 16:9 TV" means that the video has been stretched anamorphically, a feature supported by all DVD players and many TV sets. When the DVD player is set for 16:9 display, anamorphic images are enabled. When the player is set for 4:3, anamorphic is disabled, and the player discards scan lines to restore object shapes.
Because all the DVD's available scan lines are displayed in anamorphic mode, a 16:9 TV or a 4:3 TV with anamorphic squeeze will display the highest resolution.
Wide Screen TVs Can Still Have Letterboxes
HDTV is recorded for 16:9 TV sets, and the video material naturally fits the entire screen. However, some movies are shot in the Academy Flat format, which is a little bit wider (1.85:1), and a 16:9 TV will show a slight letterboxed effect. For very wide screen films shot in Panavision and Cinemascope, a 16:9 TV will still show a prominent letterbox. See anamorphic lens and letterbox.
Anamorphic mode maximizes resolution on wide screen 16:9 TVs. Standard 4:3 TVs that support anamorphic mode display more lines of vertical resolution by squeezing the image into the required space. On non-anamorphic 4:3 TVs, in order to restore the original shape of the images, the player discards lines in the vertical resolution. This is a conceptual illustration.
These are the common aspect ratios of movies and display screens.