The idea is that 72.0 DPI is just the logical/reference resolution of
dimensions that are returned by Page::size, it is independent of the
actual resolution of any data in the document files. If the dimension
in a document/page use a different reference resolution, I would say
we transform them accordingly and transparently in the back-end
itself. (Links and stuff use a different scheme where their
coordinates are inside [0,1] x [0,1] describing position w.r.t. to
page dimension.)
The resolution at which the data should be rendered is always passed
to Page::render explicitly and depends on the physical resolution of
the monitor (or possibly printer) used. (So I think typically, if you
have a 300 DPI image in a DjVu file, you would scale it down to
monitor resolution times scale factor for rendering.)
Best regards, Adam.
