[sane-devel] Epson DS1660W

[Olaf Meeuwissen]

Hi Jeff,

I've been (heavily) involved in the development of what EPSON releases
as imagescan, until March 2016 that is.

Jeff writes:

> Hallo all,
>
> There is a gscan2pdf user with a Epson DS1660W which is behaving
> strangely (in my opinion).
>
> If the user sets the brightness or contrast to any value other than 0,
> then at the next scan, the scanner return SANE_STATUS_CANCELLED. Setting
> the non-zero value itself returns SANE_STATUS_GOOD
>
> However, he is able to scan successfully with scanimage.
>
> The bug report is here:
>
> https://sourceforge.net/p/gscan2pdf/bugs/326
>
> Apart from the above, other strange things are that the device name
> starts as follows:
>
> imagescan:esci:usb:/sys/devices/pci

Odd it may seem but that actually looks correct if memory serves me
right.  The imagescan (aka utsushi) SANE backend using its esci driver
to access a device via USB.

> and
>
> the return codes bitmask is includes undefined bits, e.g.
>
> 21959
>
> which I am interpreting as
>
> ? + ? + ? + ? + ? + ? + SANE_INFO_RELOAD_PARAMS +
> SANE_INFO_RELOAD_OPTIONS + SANE_INFO_INEXACT

I cursorily checked the backend's C++ code.  It uses operator|= to set
flags in the info variable.  It does not seem to clear the incoming
value.  Any chance you're seeing bits that the frontend did not bother
to initialize?

> Has the backend implemented an extension to SANE? Does it therefore ship
> its own version of scanimage?

It does not ship its own scanimage version and does not implement any
SANE extension, TTBOMK.  It does of course ship imagescan ;-)

> Any insight welcome.

FTR, you can find the imagescan code at

  https://gitlab.com/utsushi/imagescan

Hope this helps,
--
Olaf Meeuwissen, LPIC-2            FSF Associate Member since 2004-01-27
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