kopia lustrzana https://gitlab.com/sane-project/website
88 wiersze
4.5 KiB
HTML
88 wiersze
4.5 KiB
HTML
<!-- received="Fri Aug 29 08:52:04 1997 MST" -->
|
|
<!-- sent="Fri, 29 Aug 1997 17:04:01 +0200" -->
|
|
<!-- name="Rainer krienke" -->
|
|
<!-- email="krienke@mailhost.uni-koblenz.de" -->
|
|
<!-- subject="Backtracking in color scanning" -->
|
|
<!-- id="199708291522.RAA10742@fritz.sema.be" -->
|
|
<!-- inreplyto="" -->
|
|
<title>sane-devel: Backtracking in color scanning</title>
|
|
<h1>Backtracking in color scanning</h1>
|
|
<b>Rainer krienke</b> (<a href="mailto:krienke@mailhost.uni-koblenz.de"><i>krienke@mailhost.uni-koblenz.de</i></a>)<br>
|
|
<i>Fri, 29 Aug 1997 17:04:01 +0200</i>
|
|
<p>
|
|
<ul>
|
|
<li> <b>Messages sorted by:</b> <a href="date.html#101">[ date ]</a><a href="index.html#101">[ thread ]</a><a href="subject.html#101">[ subject ]</a><a href="author.html#101">[ author ]</a>
|
|
<!-- next="start" -->
|
|
<li> <b>Next message:</b> <a href="0102.html">David Mosberger-Tang: "Re: Backtracking in color scanning"</a>
|
|
<li> <b>Previous message:</b> <a href="0100.html">Didier Carlier: "Nikon LS-1000"</a>
|
|
<!-- nextthread="start" -->
|
|
<li> <b>Next in thread:</b> <a href="0105.html">Rainer Krienke: "Re: Backtracking in color scanning"</a>
|
|
<li> <b>Maybe reply:</b> <a href="0105.html">Rainer Krienke: "Re: Backtracking in color scanning"</a>
|
|
<li> <b>Maybe reply:</b> <a href="0112.html">Rainer Krienke: "Re: Backtracking in color scanning"</a>
|
|
<li> <b>Maybe reply:</b> <a href="0113.html">Mathias Weigt: "Re: Backtracking in color scanning"</a>
|
|
<!-- reply="end" -->
|
|
</ul>
|
|
<!-- body="start" -->
|
|
Hello,<br>
|
|
<p>
|
|
I use sane0.62 with my mustek 1200spro (connected to an ADAPTEC 2940<br>
|
|
scsi adapter). I have a question about backtracking. <br>
|
|
<p>
|
|
<p>
|
|
When I scan color images at resolutions of say 300dpi the scan process<br>
|
|
works right, but is very slow. This is because the scanner scans some<br>
|
|
line and then goes back (that=B4s backtracking if I understood it right)<br>
|
|
and then scans the next lines. Looking at the scanner it seems the the<br>
|
|
way the scanner goes back is just a little smaller then the way it has<br>
|
|
scanned before. Scanning a paper of size DINA4 (~30cm at length, ~21cm<br>
|
|
wide) at 300dpi takes about 2min and 45 sec. If I scan at 100 dpi the<br>
|
|
effect is basically still there but the sanner then scans a larger area<br>
|
|
in one step before going back only a little. So the whole thing works<br>
|
|
faster.<br>
|
|
<p>
|
|
What suprises me a lot, is that under windows doing the same scanprocess<br>
|
|
at the same resolution (via the mustec-twain driver) does not cause<br>
|
|
backtracking to occur and is completed much much faster (not even half<br>
|
|
the time).<br>
|
|
<p>
|
|
So is this backtracking really needed, can scan speed be increased even<br>
|
|
with backtracking? What I tried is to call scanimage with the option<br>
|
|
--speed Fastest and I commented out the option -- option strip-height<br>
|
|
in my mustek.conf file and set the buffersize SG_BIG_BUFF to the value<br>
|
|
documented in sane-scsi (130560), recompiled kernel and sane.<br>
|
|
<p>
|
|
Can someone try to explain this difference between twain-windows and<br>
|
|
sane-linux to me ?<br>
|
|
<p>
|
|
Thanks a lot,<br>
|
|
<p>
|
|
Rainer<br>
|
|
<p>
|
|
<pre>
|
|
--
|
|
----------------------------------------------------------------------
|
|
Rainer Krienke <a href="mailto:krienke@informatik.uni-koblenz.de">krienke@informatik.uni-koblenz.de</a>
|
|
Universitaet Koblenz, <a href="http://www.uni-koblenz.de/~krienke">http://www.uni-koblenz.de/~krienke</a>
|
|
Rechenzentrum, Voice: +49 261 9119-641
|
|
Rheinau 3-4, 56075 Koblenz, Germany Fax: +49 261 9119-499
|
|
----------------------------------------------------------------------
|
|
<p>
|
|
<pre>
|
|
--
|
|
Source code, list archive, and docs: <a href="http://www.azstarnet.com/~axplinux/sane/">http://www.azstarnet.com/~axplinux/sane/</a>
|
|
To unsubscribe: mail -s unsubscribe <a href="mailto:sane-devel-request@listserv.azstarnet.com">sane-devel-request@listserv.azstarnet.com</a>
|
|
</pre>
|
|
<!-- body="end" -->
|
|
<p>
|
|
<ul>
|
|
<!-- next="start" -->
|
|
<li> <b>Next message:</b> <a href="0102.html">David Mosberger-Tang: "Re: Backtracking in color scanning"</a>
|
|
<li> <b>Previous message:</b> <a href="0100.html">Didier Carlier: "Nikon LS-1000"</a>
|
|
<!-- nextthread="start" -->
|
|
<li> <b>Next in thread:</b> <a href="0105.html">Rainer Krienke: "Re: Backtracking in color scanning"</a>
|
|
<li> <b>Maybe reply:</b> <a href="0105.html">Rainer Krienke: "Re: Backtracking in color scanning"</a>
|
|
<li> <b>Maybe reply:</b> <a href="0112.html">Rainer Krienke: "Re: Backtracking in color scanning"</a>
|
|
<li> <b>Maybe reply:</b> <a href="0113.html">Mathias Weigt: "Re: Backtracking in color scanning"</a>
|
|
<!-- reply="end" -->
|
|
</ul>
|