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| Home › Support › Breeze Help > "File formats: JPEG" options dialog box
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This dialog allows you to specify parameters of JPEG file / stream format.
The following options allow you to specify JPEG file / stream:
"Quality" slider, edit, spin boxes
These control boxes allow you specifying a quality of the compressed JPEG
image.
"Color space" group box
This group box allow you to specify color space of JPEG image.
JPEG format allows to save color image in its original color form or convert
color image into a gray (black and white) image. Size of a gray JPEG file is
smaller than the size of a color JPEG file. Using gray image may be useful when
color information is not required and size of the JPEG file has to be as small
as possible for the given level of quality.
Remarks
JPEG is a lossy compression algorithm. When image is converted into the JPEG
format some color information is lost. As a result a quality of the image
compressed with JPEG algorithm becomes lower than it was originally in the
uncompressed image. The loss of a quality depends on the level of compression.
The higher level of compression in JPEG file, the lower level of quality.
Practically it means that there has to be found a compromise between quality
and the level of compression acceptable for the concrete situation.
Level of quality in the uncompressed image is defined as 100%. Level of quality
about 80% is considered usually as a high. Level a quality about 50% - 60% is
considered as an average. And level of quality about 20% - 40% is considered as
a low. These estimations are approximate, and may be different under specific
conditions.
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