On 2 September 2016 at 21:50, G. Allegri <gioha...@gmail.com> wrote: > +1 > > I would also make min/max the default option, because I've has many users > (mostly newcomers) were struggling too find out why some pixels were not > displaying as expected. It was because the statistics weren't including > some, few, important pixels.
Yes please! There's so many users on stackexchange who get confused with this same issue. Nyall > Anyway I know that, generally, cutting the tails provide a better visual > result. > > giovanni > > > Il 02/set/2016 12:39, "Even Rouault" <even.roua...@spatialys.com> ha > scritto: >> >> Hi, >> >> There has been interest expressed to improve the usability of the contrast >> enhancement function. Basically there are workflows where you want the >> min/max >> values used by contrast enhancement to be updated each time you pan or >> zoom >> the canvas. From what I've seen, here's what currently exists: >> - a long method (6 clicks): through the Style tab of the layer properties >> - a faster method (2 clicks): through the "Strech using current extent" of >> the >> contextual menu of the layer panel. >> >> When you have several rasters loaded, even the 2-click method is >> inconvenient, >> so there's a need for a 0-click solution (once the layers have been >> configured) >> >> Another shortcoming in the current implementation is that the settings of >> the >> "Load min/max values" foldable group are not persistant, which requires >> re- >> setting them if you're not happy with the default Cumlative count cut >> method. >> And if you use the "Strech using current extent" menu item, the genuine >> min/max values are used (not the 2-98% cumulative count cut) >> >> So I was thinking to something along the following lines: >> - make the min/max settings persistant >> - remove the "Load" button and "Clip extent to canvas" checkbox, and >> replace >> them by 3 radio buttons to determine the scope of statistics : "Whole >> raster", >> "Current canvas" and "Updated canvas". See the attached >> proposal_min_max.png. >> The function of the Load button would be replaced by the general Apply / >> OK >> buttons. >> - when the user manually enters the min/max values, the 2 groups of radio >> buttons (method to compute min/max and scope of statistics) would be >> unchecked >> so that is is clear that they don't come from computed statistics. I also >> think that when you select "Current canvas", once the Apply/OK buttons >> have >> been pushed, the checked state of Current canvas shouldn't be saved. This >> way >> when you display the layer properties you have a good idea of where the >> current min/max values come from. >> - make the "Strech using current extent" method honour the way min/max are >> computed in the min/max settings instead of using systematically the >> min/max. >> So when "Updated canvas" would be selected, it would have no (extra) >> effect as >> expected. >> >> Any opinions ? >> >> Even >> >> -- >> Spatialys - Geospatial professional services >> http://www.spatialys.com >> >> _______________________________________________ >> Qgis-developer mailing list >> Qgis-developer@lists.osgeo.org >> List info: http://lists.osgeo.org/mailman/listinfo/qgis-developer >> Unsubscribe: http://lists.osgeo.org/mailman/listinfo/qgis-developer > > > _______________________________________________ > Qgis-developer mailing list > Qgis-developer@lists.osgeo.org > List info: http://lists.osgeo.org/mailman/listinfo/qgis-developer > Unsubscribe: http://lists.osgeo.org/mailman/listinfo/qgis-developer _______________________________________________ Qgis-developer mailing list Qgis-developer@lists.osgeo.org List info: http://lists.osgeo.org/mailman/listinfo/qgis-developer Unsubscribe: http://lists.osgeo.org/mailman/listinfo/qgis-developer
