[GRASS-user] Grass : synchronized view for photo-interpretation?

[Nikos Alexandris]

image wrote:
> Hello,
 
> We have to do a photo-interpretation project. We have to display
> simultaneously TWO data : one raster raw data (to capture vector features
> from) + another raster data to assist in the interpretation. So we would
> like divide classic qgis interface into 2 views. Indeed we would like
> display these 2 raster data thanks to a synchronized view.
> 
> Displaying view left : raw data. Displaying view right : assist reference
> 
> Is it possible to do that with grass? If not is it possible to do that with
> another soft or application?

As far as I know, the options are:

1) the g.gui.mapswipe wx-GUI module in GRASS GIS ver. 7, 
<http://grass.osgeo.org/grass70/manuals/g.gui.mapswipe.html> offers mirrored 
view or "sliding over" for 2 maps. It's really nice but lacks of "live 
querying of raster value under the pointer" for example.

2) the Dockable Mirror Map plugin in QGIS, 
<http://hub.qgis.org/projects/dockablemirrormap> which offers 2 or more simlpe 
mirrors of selected layers (I think both, raster and vector). 

3) OpenEV from the FWTools collection, <http://openev.sourceforge.net/>

Personally, I would recommend the OpenEV Viewer. It is _still_ the fastest 
raster/vector viewer alive (at least I experience it that way). You can open 2 
or more views and "link" them so as you can simultaneously view 2 or more 
raster/vector maps supported by a "mirrored" cursor. You can even create/edit 
vector layers (points, lines, polygons). It's simply superbe for image 
interpretation and, I'd say, exactly what you need!

Best of success, Nikos