Multiplier values are limited to 25%,
50%, 100%, 200%, and 400%.
Understanding the Pixel Aspect Ratio
You probably know that the images on your computer screen consist of tiny dots called
pixels.You may even know that pixel is short for picture element, and that all pixels are rectangular.
What you may not realize, however, is that all pixels are not created equal.What
sets them apart is their shapes, which are described in terms of aspect ratio??”the proportion
of their width to their height. Images created for display on computer screens have
square pixels, with an aspect ratio of 1.0. Images prepared for display on TV screens are
another matter. Images generated for NTSC D1-standard TVs used in North America typically
measure 720?—486 pixels, and consist of pixels that are taller than they are wide,with
aspect ratios between 0.86 and 0.90. Images created for PAL-standard TVs (used in
Europe) measure 720?—576 pixels, but consist of pixels wider than they are tall,with aspect
ratios of 1.01 to 1.06.
In 1953, the National Television Standards Committee (NTSC) developed the North
American television broadcast standard.
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