ADS Technologies USBAV-708 INSTANT VIDEOMPX, Руководство пользователя

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The
Guide
66
Cro
p
a
nd
Re
siz
e
Cr
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p
in
g a
nd
re
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ia
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nc
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,
Wh
y c
ro
p o
r r
es
iz
e?
Crop and Resize
Cropping and resizing are two
of the most basic filters than
can be applied to video, and
yet not all video applications
provide this functionality. Both
techniques alter the
dimensions of the video area,
cropping by discarding areas of the video and resizing by
scaling the video along its horizontal and/or vertical axis.
The DivX encoder ensures that these two filter operations can
be performed from any application capable of compressing
DivX video regardless of whether the application itself includes
this functionality by providing its own crop and resize controls.
The encoders internal filters are optimized with regards to quality and
performance and may offer better performance than those in your video
application.
By appropriately cropping and resizing a source it is possible to improve the
quality of the encoded video as well as decrease encoding time.
Cropping is most useful when processing video sources that feature borders
around the exterior of the picture area, a common attribute of both widescreen
DVD video and analogue capture content.
Although the borders themselves are encoded
with relative ease, where the border meets the
picture a high contrast edge is created that
consumes a large number of bits when
encoded.
Cropping and resizing via the encoder
Why crop or resize?
Cropping
Re
siz
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