[sane-devel] Re: new SANE hpoj backend

David Paschal paschal@rcsis.com
Sun, 17 Mar 2002 03:27:05 -0800


Michael Piotrowski wrote in response to me:
> With "photo-card" you're referring to memory cards as used by digital
> cameras?
Yes.  They can be addressed in sectors (typically 512 bytes/sector), and
typically contain a FAT or VFAT file system to store files (images or
otherwise).  HP PhotoSmart printers provide two protocols (per-sector and
per-file) to access the photo card readers.  I already have support for
the per-sector mode in conjunction with mtools, and I plan to add support
for the per-file mode in conjunction with SANE and/or gPhoto2 (I'm aware
of the SANE generic gPhoto2 backend).

> > I'm considering eventually either adding a photo-card-reader source
> > to the hpoj backend (along with a fax-receive source) or writing a
> > gPhoto2 backend, and for the former case your definition of
> > "multi-function" wouldn't be quite accurate.  (FWIW currently I have
> > photo-card access through mtools, but I'm looking to provide
> > additional interface choices.)
> 
> So, once you added that, would it be possible to use SANE to read a
> memory card in a PhotoSmart printer? Hmm. Normally I'd still refer to
> a device like this as a "printer," but I guess that would be very
> confusing ;-)
> 
> Does it make sense at all to lump all of these devices together under
> a *single* term when their capabilities vary so widely?
The idea is to add an option to the backend that selects the image source
to be either the scanner, fax modem, or photo-card reader.  A PhotoSmart
printer would only have the photo-card source option.  Some OfficeJets
would either have only the scan source, the scan and fax sources, or the
scan and photo-card sources.  Even though the device "capabilities vary
so widely," I think it makes sense "to lump [them] together under a
*single* term," because in the interest of better integration they would
be lumped together under a single backend.

Henning Meier-Geinitz wrote:
> I have added "multi-function peripheral" to the list of types in the
> SANE standard  (CVS).
Thanks.  I will update my (external) backend accordingly.

David