Support for vectorizing very large rasters
------------------------------------------

                 Key: GEOT-3121
                 URL: http://jira.codehaus.org/browse/GEOT-3121
             Project: GeoTools
          Issue Type: Improvement
            Reporter: Michael Bedward
            Assignee: Michael Bedward
            Priority: Minor


RasterToVectorProcess accumulates line segments in memory as it processes the 
input grid coverage and then passes them to JTS Polygonizer en masse. When 
vectorizing all boundaries in a very large coverage the line segments can 
exhaust available memory before the process is completed.

The following is one idea for addressing this:
# Modify RasterToVectorProcess to return a DataStore instead of a 
FeatureCollection.
# Allow the user to provide a DataStore to use as the destination and a name to 
assign to the destination SimpleFeatureType. If not provided a new DataStore 
will be created and a default name used.
# Process the input raster in sections based on tiles or some number of rows 
(rows might be safest).
# The line segments generated in each section are polygonized to create new 
SimpleFeatures which are added to the destination DataStore.
# In the case of raster regions extending beyond the boundaries of an input 
section, temporary edges are added so that valid polygons can be created. The 
location of these edges is recorded so that the resulting features can be 
merged as a final step in the process.

I don't know if the above is the best approach. Comments welcome !



-- 
This message is automatically generated by JIRA.
-
If you think it was sent incorrectly contact one of the administrators: 
http://jira.codehaus.org/secure/Administrators.jspa
-
For more information on JIRA, see: http://www.atlassian.com/software/jira

        

------------------------------------------------------------------------------

_______________________________________________
Geotools-devel mailing list
Geotools-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/geotools-devel

Reply via email to