On Mon, 2008-05-26 at 14:56 +0200, David Necas (Yeti) wrote: > On Fri, May 23, 2008 at 12:15:23PM +0200, Renzo Stheins wrote: > > Firstly, the statistics for the grains is incorrect, only 2 grains are > > identified when using the inverted mask. > > I am not sure what `when using the inverted mask' means. The mask > defines the marked grains, in the sense that grains just *are* > continuous parts of the mask. (Grain marking and evaluation are > completely separate operations since either can be done in many ways and > one may also want to modify marked areas somehow between.) > > If you invert the mask it is likely that it has only 2 continuous parts > now, but then the statistics works as expected (for some value of > expected at least). > > > When disabling the invert of the mask, the number of grains is too high > > (301), while a manual count yields 225. > > While you might hit an unknown bug, I suppose this is more likely caused > by different definitions of individual grain. As I wrote above, the > number of grains is the number of continuous parts of the mask that > marks them (where pixels touching only with a corner are considered > separate). > > You can use the grain measurement tool > > > http://gwyddion.net/documentation/user-guide/grain-analysis.html#grain-measure > > to display the ordinal number of individual grains and thus check what > parts constitute which grain. > > > Is there some setting I can adjust to get the correct grain count and > > size distribution? > > Well, you need to get them marked according to your notion of a grain. > The counting should work then. It can be possible to achieve this with > some adjustment of the watershed algorithm parameters. If the algorithm > produces tiny (noise) grains, these can be removed with the grain > remove-by-threshold function. > > > Secondly, when wanting to plot the distribution of the grains (with only > > "Equivalent Disc Radius" selected) this results in a program crash. > > > > Selecting only other options, e.g. "Equivalent square side" also result > > in a crash. > > > > Exporting the raw data does work however. > > I am afraid this is a long known bug. It was found and fixed almost > immediately after the release of 2.9, the patch is here: > > > http://gwyddion.svn.sourceforge.net/viewvc/gwyddion/trunk/gwyddion/modules/process/grain_dist.c?r1=8455&r2=8664&view=patch > > However, this can help you only if you build Gwyddion from source code. > The next version will have this bug fixed.
If you don't want (can't) recompile Gwyddion for Windows you can also downgrade GTK+ to, I think, version 2.8 (I can't check right now). You have to go down 1 or two numbers from the latest release. This worked for our windows installations. In Linux of course recompiling is probably easier. Gregor > > Yeti > > > ------------------------------------------------------------------------- > This SF.net email is sponsored by: Microsoft > Defy all challenges. Microsoft(R) Visual Studio 2008. > http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ > _______________________________________________ > Gwyddion-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/gwyddion-users -- !!I am trying to shift my personal mail to this address!! plz update your addressbook Gregor Hlawacek -- http://www.unileoben.ac.at/~hlawacek Proleber Straße 60/7 -- +43 650 3592145 8700 Leoben, Austria (o_ (o_ (o<)< (o< -! //\ //\ //\ //\ V_/_ [ ]/_ V_/_ V_/_ penguin eating fish travelling being noisy GPG ID: FBCDF36E GPG Finger Print: 1AA0 DC5C 186F 6144 01F0 8FB2 7ABD D7FB FBCD F36E ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ Gwyddion-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/gwyddion-users
