8.8

compression. Select Auto to let the application choose the best compression
method automatically. Note that configurations that were created with an earlier
version of PReS Workflow and that included tasks set not to use any compression
will by default be set to use the Flate compression method.
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Downsampling: Select the down sampling option. Down sampling reduces image
size by breaking images down into small areas in which multiple pixels are
replaced by single pixels. The Grayscale resolution you enter in the following box is
used to control the down sampling process. Select None to prevent grayscale down
sampling. Select Average to average pixel shades in each sample area and to
replace the entire area with a pixel of the average shade. Select Subsample to use
a pixel in the center of the sample area and replace the entire area with that pixel
value. This method is significantly faster, but results in images that are less smooth.
Select Bicubic to use a weighted average to determine pixel shades. This method is
the slowest but most precise and results in the smoothest tonal gradations.
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Resolution: Select the resolution to use for grayscale images. Note that this setting
has an impact on the grayscale down sampling process.
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Color images group
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Compression: Select the compression to use for the color images. Flate is a
lossless compression method, so no data is lost in the process. It works well on
images with large areas of single shades or repeating patterns, such as screen
shots and simple images created with paint or drawing programs. JPEG removes
image data and may reduce image quality, but may be suitable for continuous-tone
photographs containing more detail than can be reproduced onscreen or in print.
Since JPEG eliminates data, it can achieve much smaller file sizes than Flate
compression. Select Auto to let the application choose the best compression
method automatically. Note that configurations that were created with an earlier
version of PReS Workflow and that included tasks set not to use any compression
will by default be set to use the Flate compression method.
l
Downsampling: Select the down sampling option. Down sampling reduces image
size by breaking images down into small areas in which multiple pixels are
replaced by single pixels. The Color resolution you enter in the following box is
used to control the down sampling process. Select None to prevent grayscale down
sampling. Select Average to average pixel color in each sample area and to replace
the entire area with a pixel of the average color. Select Subsample to use a pixel in
the center of the sample area and replace the entire area with that pixel value. This
method is significantly faster, but results in images that are less smooth. Select
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