Comments on Prepare Rasters for Maxent versus Find ArcGIS Rasters and Project to Template in MGET

On my page for the Prepare Rasters for Maxent Tool for ArcGIS I made a comment about its application versus another tool called Find ArcGIS Rasters and Project to Template in the Marine Geospatial Ecology Toolbox.  To access that page click HERE .  Here is the text of that comment:

The Marine Geospatial Ecology Tools for ArcGIS (http://mgel.env.duke.edu/mget) is an excellent toolbox that includes much of the functionality of the Prepare Rasters for Maxent toolbox. I highly recommend checking it out. In particular, check out the Find ArcGIS Rasters and Project to Template tool which will batch project and clip all rasters to a template. One primary difference between that tool and Prepare Rasters for Maxent is that Prepare Rasters for Maxent has built-in steps to resample and fill in missing data. If you know that you have gaps in your data then Prepare Rasters for Maxent may be your best bet. If you don't think that you have gaps or they are minor then consider Find ArcGIS Rasters and Project to Template as a speedier alternative. You can create a template raster by multiplying all of your rasters together in the Raster Calculator. By default this will take the intersection of all of the rasters resulting in a template that is smaller than any one of the inputs.

Random forest and ArcScan

Recently I've been helping some colleagues in my department convert some historical maps into contour lines.  They are at the stage of using ArcScan to convert old scanned topographic maps into contour lines. Interestingly, ArcScan doesn't make use of multi-band image files, but rather single-band grayscale images. When trying to pull out contour lines as distinct from other types of lines this became problematic. Using a simple band thresholding method browns and grays tended to get confused.

The solution?  I used the Marine Geospatial Ecology Tools to perform a random forest classification to separate brown lines from all other colored lines. The results were really impressive.  Pretty much all of the gray lines were removed.  See the picture below for an illustration of the result.

Original scanned topographic map with contour lines in brown and other lines in black/gray.

The result when using a simple band thresholding approach. Black lines represent cells that will be used in the vectorization process.

The result from the random forest classification plus a small amount of speckle removal using the regiongroup tool in ArcGIS.