Datasheet

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Upgrading the Basic Stuff
Taking a look at aspect ratio
If you’ve ever wondered why movies appear
onscreen with a black band at the top and
bottom, or why your photos get cut off a little
differently on 8-by-10 prints as opposed to
6-by-9s, you’ve bumped into the effects of the
aspect ratio.
The aspect ratio of a picture is the ratio of the
picture’s width to its height. For many years,
televisions and (almost) all computer screens
used the 4:3 aspect ratio, where the ratio of a
screen’s width to height is 4 to 3. In the follow-
ing figure, you see a photo taken with a typical
electronic camera. It produces pictures in a 4:3
aspect ratio.
The earliest movies were shot at 4:3, but
Hollywood quickly found that wider screens
led to more spectacular films. Over time, the
aspect ratio for movies changed, but TV stayed
the same — and computer screens aped TV.
Nowadays, Hollywood movies use several
different aspect ratios, but home theaters all
over the world have mostly settled on the 16:9
aspect ratio (shown in the following figure),
which has become the standard for high-
definition TV (HDTV).