8.8

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Grayscale images group
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Grayscale compression: Select the compression to use for the grayscale 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.
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Grayscale down sampling: 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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Grayscale 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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Color 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.
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