[sane-devel] Scanning from fujitsu ScanSnap S1500 Error during device I/O

[m. allan noah]

On Fri, Feb 4, 2011 at 12:16 PM, Simon Matter <simon.matter at invoca.ch> wrote:
>> No, Markus has uncovered a real bug. The S1500 chokes when doing high
>> resolution duplex scans. The backend reads data from both sides of the
>> paper, and buffers the back side. Unfortunately, we read too far ahead
>> on the backside, and the scanner has problems.
>
> I have no idea if this could be related but I have recently tested an S510
> which one of our users was using at home. He said the scanner doesn't work
> fine anymore. I thought of course you can not compare to the bigger ones
> like fi-6230 bunt when I tried to scan duplex at - I think it was 300dpi -
> it was veeeeeeery slow. It felt like being 1 or 2 minutes and that really
> seems to much :)
>
> What I remember is that it took half of the A4 paper quite fast and then
> waited a long time, scanned a bit more, waited and so on until the page
> was finished. The output file itself was looking fine.
>
> Any ideas if that's related somehow, at least I guess the S510 and S1500
> may be from the same "family".

I think perhaps there is a relationship. You said "doesn't work fine
anymore", which implies that it did work fine, and then something
changed. Perhaps an upgrade from sane-backends 1.0.20 to 1.0.21?

I have made some changes in the duplex handling code in the past year,
which appear to resolve Markus' problem in the git version. They might
also improve the pausing issue you described. I still do see some
pausing at high resolution with the fi-6110, but nothing like minutes,
only 10-20 seconds.

Perhaps one of you guys could test a current git snapshot? we are
preparing for release, and I'd like to fix it first.

allan

-- 
"The truth is an offense, but not a sin"