User manual

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10.4 Colour scanning
Colour scanning is available in all scanning modes, for all document types. Please see 10.1.
During application scanning, automatic switching between black white and colour is executed based
on a flag in the DMS file. Please see ePHOENIX Document Capture User Manual, section 3.8.1.
10.4.1 Automatic colour detection
Automatic Color detection causes an image to be processed as colour once the set threshold has
been reached.
Note:
Automatic colour detection is only available for application scanning.
Figure 54: color detection settings
The Threshold property is the minimum colourfulness threshold level. The average threshold of a
neighbourhood is compared to the threshold value that is set. If the threshold value is set to 0, then
all neighbourhoods are colourful because the average threshold of each neighbourhood is probably
greater than 0. If the threshold value is set to 256, then no neighbourhoods are colourful.
For most applications, the default colourfulness threshold is probably suitable. However, some
applications might require adjustment of this parameter. If only bright colours should trigger colour
processing, the colourfulness threshold might be increased to 200. If very pale colours need to be
detected, it might be lowered to 50.
The image is broken into cells and the Sample Size property sets the cell size for checking the
colour content.
For most applications, the default sampling neighbourhood is probably suitable. However, some
applications might require adjustment of these parameters. If the resolution is especially low (100
dpi or less), the sampling neighbourhood might be reduced to 1 x 1 or 2 x 2, and if it is high (600 dpi
or more), it might be increased to 5 x 5. Also, if the colour channel misalignment is particularly high,
the sampling neighbourhood might be increased to compensate.