didjvu - 0.8.2-2+deb10u1 main

The DjVu graphics format is very effective because it uses
multiple layers which are differently compressed. For the
derivation of the bitonal foreground layer ("mask") of
(scanned document) images ("segmentation") didjvu uses the
Gamera framework.
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In the same process didjvu encodes the foreground mask together
with the background counterpart into DjVu. That's also possible
for a stack of images which can be processes into a bundled DjVu
container very easily. The results are suitable for getting high-
quality OCR data even from problematic scans from old documents.
Furthermore, didjvu is capable of processing bitonal segmentation on
colour scans.