GIMP – cutting out an object, fuzzy edges (or not fuzzy)

  1. Open image
  2. Right click the layer and Add Alpha Channel
  3. Get the Tools->Selection->Free Select lasso tool and click round the edge (just inside) of the object.
  4. Select->Feather (and an amount for feathering)
  5. Select->Invert (causes the background to be selected)
  6. Select->Clear

For a hard edged outline, instead of feathering the outline can be clicked round using the Select->Scissors tool and carefully clicking all round adding/moving the points as required.


DXF File from OS DEM Data (3 colour)

1 Open QGIS with OS DEM data loaded

2 QGIS->Raster->Extraction->Clipper  save area as new file (.tif)

3 QGIS new project, drag in the .tif

4 Select the tif (DEM) data and then QGIS->Raster->Extraction->Contours

5 Select the new contours file and right click Properties. Instead of Single Symbol select rule-based.  Load in the 3 colour contour rule.

6 Save as DXF (use correct scaling)