[GRASS-dev] [GRASS GIS] #3210: r.texture: bug when non continuous series of values

[GRASS GIS]

#3210: r.texture: bug when non continuous series of values
--------------------------+-------------------------
  Reporter:  mlennert     |      Owner:  grass-dev@…
      Type:  defect       |     Status:  reopened
  Priority:  normal       |  Milestone:  7.2.0
 Component:  Raster       |    Version:  svn-trunk
Resolution:               |   Keywords:  r.texture
       CPU:  Unspecified  |   Platform:  Unspecified
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Comment (by mmetz):

 Replying to [comment:15 mlennert]:
 > Reopening this ticket as the modifications seem to include an error in
 the Contrast measure calculations. IIUC, the f2_contrast() function has to
 return the sum and not the bigsum as bigsum is never calculated (commented
 out) and the result is thus always 0:
 >
 >
 > {{{
 > --- h_measure.c       (révision 69847)
 > +++ h_measure.c       (copie de travail)
 > @@ -434,7 +434,7 @@
 >       }
 >      }
 >
 > -    return bigsum;
 > +    return sum;
 > }}}
 >
 > MarkusM, can you confirm this ?

 Yes, thanks for testing! Fixed in all branches with r69866-8. The new
 changes also include a small optimization for f2_contrast, reducing the
 number of iterations by half.

 >
 > With this change, the results are much more useful than the Contrast
 measurement output of <= g7.0.5 !
 >
 > More generally, I think the difference in some of the measure are so
 important that this is probably a candidate for
 [https://trac.osgeo.org/grass/wiki/RFC/5_Errata RFC5 style treatment].

 Probably yes.

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Ticket URL: <https://trac.osgeo.org/grass/ticket/3210#comment:16>
GRASS GIS <https://grass.osgeo.org>