Anamorphic widescreen

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Anamorphic widescreen is a video technique that utilizes rectangular (wide) pixels to store a widescreen picture into standard 4:3 aspect ratio. It was originally devised for widescreen television sets with a 16:9 aspect ratio but not in use before the advent of DVD and DVB.

Contents

[edit] DVD Video

DVDs using anamorphic widescreen are very similar to anamorphic film negatives, where the rectangular image is optically-squeezed (horizontally) to fit inside the almost-square storage space. When viewed on standard 4:3 televisions without adjustment, the anamorphic image will look compressed, such that the actors look exceptionally thin or tall (and a circle will appear as a vertical oval). Changing the DVD player's menu to the "4:3 letterbox" setting will digitally-insert black bars to the top/bottom of the image, thus eliminating the distortion and allowing the movie to be viewed in letterbox format.

Most video DVDs include a data marker that automatically selects the best aspect ratio for the video to be displayed. This way, the full area of a 16:9 widescreen TV set can be utilized without changing the resolution of video DVDs. However, sources wider than 16:9 (e.g., the common cinema 1.85:1 or superwide 2.35:1 aspect ratio), must still be letterboxed to the 16:9 frame with thin black bars.

Note that neither 720x480 (1.5:1) nor 720x576 (1.25:1) are in 4:3 (1.3333:1) display aspect ratio. Instead each pixel can have a "narrow" aspect ratio of 1.1:1 in the standard 4:3 full-frame display, or a "wide" ratio of 1.421:1 for 16:9 widescreen.

DVDs with a 16:9 aspect ratio are typically labeled "anamorphic widescreen", "enhanced for 16:9", "enhanced for widescreen televisions" or similar, though currently there is no labeling standard. Otherwise, the movie will only support the standard full-frame display and will simply be "letterboxed".

[edit] Packaging

Image:MGM-Pkg.jpg
MGM Anamorphic DVD Packaging Sample.
Image:Univ-Pkg.JPG
Universal Anamorphic DVD Packaging Sample.

There has been no clear standardization for companies to follow regarding the advertisement of anamorphically enhanced widescreen DVD's. Some companies such as Universal include the aspect ratio of the movie. Below are how various companies advertise their anamorphic DVD movies on their packaging:

[edit] Film

Even film, recorded on standard 35mm 4:3 aspect ratio with a sound track on the picture, uses an anamorphic (horizontally compressed) storage on film. An anamorphic lens corrects the picture. See anamorphic format for details.

[edit] Television

Major digital television channels in Europe are often broadcast in anamorphic widescreen in standard definition. In almost all cases, there is also the ability for the channel to switch between 4:3 and 16:9 as necessary, depending on programming. Set-top boxes, including Sky Digiboxes have the ability to switch the television set to the correct aspect ratio by means of SCART. The main five terrestrial networks in the UK are broadcast in 16:9 on digital.

[edit] See also

[edit] External links

fr:Format large anamorphosé nl:Anamorf breedbeeld ja:アナモルフィック・レンズ no:Anamorfisk bredformat lt:Anamorfinis formatas

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