[QGIS-trac] Re: [Quantum GIS] #1380: No Data values are counted as values in the histogram

[Quantum GIS]

#1380: No Data values are counted as values in the histogram
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        Reporter:  alobo                             |         Owner:  timlinux     
            Type:  bug                               |        Status:  new          
        Priority:  major: does not work as expected  |     Milestone:  Version 1.6.0
       Component:  Rasters                           |       Version:  Trunk        
      Resolution:                                    |      Keywords:               
Platform_version:  ubuntu 8.04, ubuntu 9.04          |      Platform:  Linux        
        Must_fix:  Yes                               |   Status_info:  0            
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Changes (by alobo):

  * owner:  ersts => timlinux
  * status:  reopened => new


Comment:

 >  Hi Agus,
 >
 > As far as I know this is so because your raster does not define a null
 > value in the GDAL sense (use GDAL tools to set a null value for that
 > raster, NOT the QGIS raster properties)
 >

 Yes (as extremely delayed feedback to Benoit too) I plan to rewrite
 the raster histogramming at some point to not use gdal so that we can
 take into account user defined transparency settings etc. I will do
 this when I get a few hours to spare!

 Regards

 Tim

 > Hope this helps,
 > Benoit
 >
 > On 01/12/2010 17:14, Agustin Lobo wrote:
 >> Raster histograms include null values, which in many cases severely
 distorts the
 >> histograms (i.e., images in which a large part of ocean is present or
 >> just images
 >> in which the scene is not a rectangle)
 >> Also, the ability to customize the axes (in particular the x axis) is
 >> very important

-- 
Ticket URL: <https://trac.osgeo.org/qgis/ticket/1380#comment:9>
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