kopia lustrzana https://gitlab.com/sane-project/website
82 wiersze
4.5 KiB
HTML
82 wiersze
4.5 KiB
HTML
<!-- received="Wed Jun 23 14:25:44 1999 PDT" -->
|
||
<!-- sent="23 Jun 1999 14:26:49 -0700" -->
|
||
<!-- name="David Fox" -->
|
||
<!-- email="dsfox@cogsci.ucsd.edu" -->
|
||
<!-- subject="Re: Fix for grayscale scans with gamma < 1.0" -->
|
||
<!-- id="" -->
|
||
<!-- inreplyto="Wed, 23 Jun 1999 21:54:16 +0200"" -->
|
||
<title>sane-devel: Re: Fix for grayscale scans with gamma < 1.0</title>
|
||
<h1>Re: Fix for grayscale scans with gamma < 1.0</h1>
|
||
<b>David Fox</b> (<a href="mailto:dsfox@cogsci.ucsd.edu"><i>dsfox@cogsci.ucsd.edu</i></a>)<br>
|
||
<i>23 Jun 1999 14:26:49 -0700</i>
|
||
<p>
|
||
<ul>
|
||
<li> <b>Messages sorted by:</b> <a href="date.html#167">[ date ]</a><a href="index.html#167">[ thread ]</a><a href="subject.html#167">[ subject ]</a><a href="author.html#167">[ author ]</a>
|
||
<!-- next="start" -->
|
||
<li> <b>Next message:</b> <a href="0168.html">Oliver Rauch: "Re: Fix for grayscale scans with gamma < 1.0"</a>
|
||
<li> <b>Previous message:</b> <a href="0166.html">amalmin@coho.halcyon.com: "Re: Newbie question ;-)"</a>
|
||
<li> <b>In reply to:</b> <a href="0163.html">Oliver Rauch: "Re: Fix for grayscale scans with gamma < 1.0"</a>
|
||
<!-- nextthread="start" -->
|
||
<li> <b>Next in thread:</b> <a href="0168.html">Oliver Rauch: "Re: Fix for grayscale scans with gamma < 1.0"</a>
|
||
<!-- reply="end" -->
|
||
</ul>
|
||
<!-- body="start" -->
|
||
Oliver Rauch <<a href="mailto:oliver.rauch@Wolfsburg.DE">oliver.rauch@Wolfsburg.DE</a>> writes:<br>
|
||
<p>
|
||
<i>> David Fox wrote:</i><br>
|
||
<i>></i><br>
|
||
<i>> > No problem... I'm currently scanning some very old and deteriorating</i><br>
|
||
<i>> > black and white photographs, and I've noticed a couple of problems</i><br>
|
||
<i>> > with using xsane. First, the range of the xsane brightness and</i><br>
|
||
<i>> > contrast controls is much less than the range provided in scanimage,</i><br>
|
||
<i>> > at least with my HP-3c scanner using the HP back-end.</i><br>
|
||
<i>> ></i><br>
|
||
<i>> > Second, I think I will also need to be able to change the brightness</i><br>
|
||
<i>> > and contrast settings used when acquiring the preview, and see new</i><br>
|
||
<i>> > histograms and perform the usual xsane modifications in relation to</i><br>
|
||
<i>> > those new ``default'' settings.</i><br>
|
||
<i>> </i><br>
|
||
<i>> The birghtness and contrast of xsane is a software created digital gamma</i><br>
|
||
<i>> table and has nothing to do with the options the scanner makes available,</i><br>
|
||
<i>> these are still available in xsane under standard or advanced options!</i><br>
|
||
<i>> </i><br>
|
||
<i>> You can change the scanner brightness and contrast and do a new preview</i><br>
|
||
<i>> scan and see the changes in the histogram.</i><br>
|
||
<i>> I think about adding support for a preview scan with more than 8/24 bits/pixel,</i><br>
|
||
<i>> but I am not sure if that really is necessary.</i><br>
|
||
<p>
|
||
Oh, I see, I didn't understand the significance of the standard and<br>
|
||
advanced options. I think there might be a way to integrate all of<br>
|
||
these controls into a unified whole. The use of the hardware's<br>
|
||
brightness and contrast to achieve a particular goal is preferable to<br>
|
||
the use of post processing. It would also be nice to get immediate<br>
|
||
feedback of the effect of changing the ``standard'' brightness and<br>
|
||
contrast controls, the way you do with the xsane controls. I suppose<br>
|
||
that you could do a some calibration, sampling an image at various<br>
|
||
settings and construct a function representing the scanner's response<br>
|
||
curve?<br>
|
||
<p>
|
||
Maybe when you stop manipulating the controls it could actually go out<br>
|
||
and get a new preview without being asked?<br>
|
||
<pre>
|
||
--
|
||
David Fox <a href="http://hci.ucsd.edu/dsf">http://hci.ucsd.edu/dsf</a> xoF divaD
|
||
UCSD HCI Lab baL ICH DSCU
|
||
<p>
|
||
<pre>
|
||
--
|
||
Source code, list archive, and docs: <a href="http://www.mostang.com/sane/">http://www.mostang.com/sane/</a>
|
||
To unsubscribe: echo unsubscribe sane-devel | mail <a href="mailto:majordomo@mostang.com">majordomo@mostang.com</a>
|
||
</pre>
|
||
<!-- body="end" -->
|
||
<p>
|
||
<ul>
|
||
<!-- next="start" -->
|
||
<li> <b>Next message:</b> <a href="0168.html">Oliver Rauch: "Re: Fix for grayscale scans with gamma < 1.0"</a>
|
||
<li> <b>Previous message:</b> <a href="0166.html">amalmin@coho.halcyon.com: "Re: Newbie question ;-)"</a>
|
||
<li> <b>In reply to:</b> <a href="0163.html">Oliver Rauch: "Re: Fix for grayscale scans with gamma < 1.0"</a>
|
||
<!-- nextthread="start" -->
|
||
<li> <b>Next in thread:</b> <a href="0168.html">Oliver Rauch: "Re: Fix for grayscale scans with gamma < 1.0"</a>
|
||
<!-- reply="end" -->
|
||
</ul>
|