[sane-devel] Seeking Odd-Page Vertical Flipping to Support ADF-Duplex

[Olaf Meeuwissen]

"m. allan noah" <kitno455 at gmail.com> writes:

> Is it rotated, or is it mirrored?

It is not mirrored.  Most Epson ADF units turn the sheet over before
scanning the flip-side but this one doesn't.

As a matter of fact, how the flip-side comes out depends on the binding
edge of the original in combination with whether the sheet is turned
over or not.  As *most* documents are bound on the long edge, flip-sides
end up up-side-down with the ES-H300.

> allan
>
> On Thu, May 31, 2012 at 11:27 AM, Jeff Rush <jrush at taupro.com> wrote:
>> I'm working in the sane-epson2 backend, trying to get it to fully
>> support adf-duplex for scanning both sides of a page, for the Epson
>> ES-H-300 scanner.

Hmm, support for this device was added to the epkowa backend in 2006 and
an ADF related fix at the end of 2008 ...

>> I've just submitted a patch (#313667) to enable the duplexing.  It
>> works, and now I have a button on XSANE under Advanced Options.  However
>> the even (backside) page is 180-degrees rotated.
>>
>> So as I'm looking thru the driver source, I thought I'd ask if there is
>> a standard configuration/setting in one of the internal data structures
>> I can use to cause every other page to be vertically flipped?
>>
>> If not, I'm going to add to the epson2 driver some logic to invoke
>> sanei_magic_rotate() on the even-numbered pages, conditionally upon
>> whether the adf-duplex feature is enabled.  It seems this kind of logic
>> would be useful to others, and perhaps even already in the code someplace.

The epkowa backend has flipping logic as of 2.27.0.  While the released
version depends on a non-free plugin, the code includes support for
sanei_magic_rotate (and sanei_magic_deskew).

You can find the epkowa backend sources in the iscan source tarball
available from:

  http://download.ebz.epson.net/dsc/search/01/search/?OSC=LX

The latest version is 2.28.1.

Hope this helps,
-- 
Olaf Meeuwissen, LPIC-2           FLOSS Engineer -- AVASYS CORPORATION
FSF Associate Member #1962               Help support software freedom
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