[9fans] scanner support

[9fans] scanner support

[anothy]

anyone done anything for scanners under Plan 9? i've got an
HP ScanJet 4c (SCSI, color) i'd like to get working. even scuzz
would be fine. anyone got any info on how i'd make scuzz do
that, or what codes SCSI scanners want (i tried scuzz' read
just for kicks, but no luck)?
-α.

Re: [9fans] scanner support

[David Gordon Hogan]

> > 'From' memory, the SCSI-2 standard (somewhat stupidly) only specifies
> > how to get data from scanners, and says nothing about the format of
> > the data itself.
>
> That's not particularly stupid -- 9P specifies how to get data but
> not the format of the data itself.

The data in this case is a grid of pixel data.  Now it is true that
the resolution can change, and the number of bits per pixel can change,
but all these things can be handled in a uniform way (c.f. the Plan 9
3rd edition graphics model).

Re: [9fans] scanner support

[Richard Miller]

> anyone know of any other scanner software that works by
> sending scsi commands (rather than through a specialized driver)
> that might be worth trying?

Some years ago I wrote a SCSI scanner driver for a Microtek scanner on
SunOS.  I'll dig out a copy and mail it to you for general interest.
It will almost certainly be of no practical use, because as David
Hogan has observed, every scanner does things differently - not just
in the format of scanned data received but in the repertoire of
commands for controlling density, contrast, area to be scanned, etc.

-- Richard

Re: [9fans] scanner support

[Douglas A. Gwyn]

David Gordon Hogan wrote:
> 'From' memory, the SCSI-2 standard (somewhat stupidly) only specifies
> how to get data from scanners, and says nothing about the format of
> the data itself.

That's not particularly stupid -- 9P specifies how to get data but
not the format of the data itself.

> So every scanner does things differently.  To `solve' this problem,
> each scanner comes with a driver which understands the data format
> (I think the name `TWAIN' has something to do with this).

There have been a few different approaches, but TWAIN is the one
I recommend.  TWAIN developer libraries are available for Windows
and I *think* for UNIX.  The general idea is that the scanner
process is a server.

Re: [9fans] scanner support

[anothy]

//the SCSI-2 standard (somewhat stupidly) only specifies
//how to get data from scanners, and says nothing about
//the format of the data itself.

well okay, that seems like a reasonable place to start. so... anyone
done anything for getting the data from scanners? it looks like i
need the Extended Read command, which scuzz can't do but
might know something about (it's in scuzz/scsireq.h). there's also
some scanner specific stuff that might be needed, a "scan" and a
"get window" (i think) command.

on using APE:
well, that could work. i've used SANE under Unix, but it's a beast
to build. anyone know of any other scanner software that works by
sending scsi commands (rather than through a specialized driver)
that might be worth trying?
-α.

Re: [9fans] scanner support

[nigel]

[-- Attachment #1: Type: text/plain, Size: 613 bytes --]

Whether TWAIN really stands for that is reaching urban myth status.

www.twain.org used to say that it doesn't stand for anything, which
sounded like an organisation wanting to forget an embarassing past.
Now they say that it is derived from the expression "and never the
twain shall meet", and that a contest was held retrospectively to
find an acronym. They didn't like any of the suggestions, but
Technology Without An Interesting Name was one of the entries
and it has haunted them ever since. They quote the Free Online
Dictionary of Computing for added emphasis.

http://www.twain.org/faq.htm


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From: Jonathan Sergent <sergent@IO.COM>
To: 9fans@cse.psu.edu
Subject: Re: [9fans] scanner support
Date: Sun, 22 Jul 2001 19:50:31 -0700
Message-ID: <20010723025152.B78B1199EB@mail.cse.psu.edu>

>(I think the name `TWAIN' has something to do with this).

TWAIN == "Technology without an interesting name" (seriously)

For what it's worth, photopc works fine under APE for getting images
off of many types of digital cameras (over serial interfaces, not USB).

Re: [9fans] scanner support

[Jonathan Sergent]

>(I think the name `TWAIN' has something to do with this).

TWAIN == "Technology without an interesting name" (seriously)

For what it's worth, photopc works fine under APE for getting images
off of many types of digital cameras (over serial interfaces, not USB).

Re: [9fans] scanner support

[David Gordon Hogan]

> anyone done anything for scanners under Plan 9? i've got an
> HP ScanJet 4c (SCSI, color) i'd like to get working. even scuzz
> would be fine. anyone got any info on how i'd make scuzz do
> that, or what codes SCSI scanners want (i tried scuzz' read
> just for kicks, but no luck)?

'From' memory, the SCSI-2 standard (somewhat stupidly) only specifies
how to get data from scanners, and says nothing about the format of
the data itself.  (There is a field for describing the format, but
it's vendor specific).

So every scanner does things differently.  To `solve' this problem,
each scanner comes with a driver which understands the data format
(I think the name `TWAIN' has something to do with this).

`I'd rather eat Jenkins' - Monty Python.