<html>
<head>
<meta content="text/html; charset=ISO-8859-1"
http-equiv="Content-Type">
</head>
<body bgcolor="#FFFFFF" text="#000000">
Hi,<br>
<br>
At this stage the plugin only takes into account the single "nodata"
value stored in the raster metadata.<br>
You can't pass it a range of nodata values (I do not have the time
right now to add a min/max option).<br>
<br>
As a work around you could 1) use the raster calculator to "dummy"
all values below a given threshold; 2) set the nodata value to the
dummy value using the Raster->Translate tool; and 3) use the
plugin on the resulting raster to give it a colour table.<br>
Note that you then can use the resulting colour table on your
original raster file.<br>
<br>
Hope this helps,<br>
Benoit<br>
<br>
<br>
On 10/08/11 11:00, M.E.Dodd wrote:
<blockquote
cite="mid:4E7B5FE52E3BEA48AD9AB3AD11BA17A38AD3B7BD8C@KIELDERCMS1.open.ac.uk"
type="cite">
<meta http-equiv="Content-Type" content="text/html;
charset=ISO-8859-1">
<meta name="Generator" content="Microsoft Exchange Server">
<!-- converted from rtf -->
<style><!-- .EmailQuote { margin-left: 1pt; padding-left: 4pt; border-left: #800000 2px solid; } --></style>
<font face="Arial, sans-serif" size="2">
<div>I have the 1-band raster colour table plugin which has some
very nice options for colour maps however the greyscale raster
I am using has very large negative values to denote areas
where there are no data compared to a normal range of say 0-40
for the
areas were there are data. Is there a way of telling the
plugin to ignore these very large negative values when making
the scale or somehow deal with them so they are recognised as
separate from the proper data so they can all be given a
single ‘no data’ colour?</div>
<div>Actually the power distribution method initially seems to
do just what I want, it gives the no data large negative
number a single colour and produces a nice gradation in the
other numbers BUT they are shown as black and white rather
than in colour for
some reason so I end up with a blue + black and white image.</div>
<div><font face="Calibri, sans-serif" size="2"> </font></div>
</font>
<font face="monospace"><br>
-- <br>
The Open University is incorporated by Royal Charter (RC
000391), an exempt charity in England & Wales and a charity
registered in Scotland (SC 038302).</font>
<br>
<fieldset class="mimeAttachmentHeader"></fieldset>
<br>
<pre wrap="">_______________________________________________
Qgis-user mailing list
<a class="moz-txt-link-abbreviated" href="mailto:Qgis-user@lists.osgeo.org">Qgis-user@lists.osgeo.org</a>
<a class="moz-txt-link-freetext" href="http://lists.osgeo.org/mailman/listinfo/qgis-user">http://lists.osgeo.org/mailman/listinfo/qgis-user</a>
</pre>
</blockquote>
</body>
</html>