Raster Line Drawing and Labelled Polygons

GHATCHER GERRY at omdc.gso.uri.edu
Fri Sep 18 19:52:00 EDT 1992


Date sent:  18-SEP-1992 18:22:16 
Hi Greg;

>Question 1: Can Grass even import a PICT file?  If so, can Grass take  
>a scanned line image and erode the lines to single pixel widths?

You can use pbmplus to create a file which can be used as a raster
layer in an xy region. Steps -> tifftopnm|pnmtopgm|pgmtopbm, then
use wc -l to see how many lines are in the file, followed by tail to
extract all but the ascii header lines from the file, be sure the that the
file is correct by multiplying #rows by #col and seeing if this
matches the file size EXACTLY, and then move the file to
$LOCATION/dig/filename. You will have to create the $LOCATION/cellhd/
file by hand using an editor. The problem will be in registering the
image to a coordinate system. For this refer to 'GRASS Tutorial:
Image Processing' by Victoria Harmon and Michael Shapiro.

>
>Question 2:  .....

I can't help you here.

Good luck,

Gerry Hatcher                   

*** Soon entering the job market with an MS in OCEAN ENGINEERING.  ***
*** PLEASE INQUIRE for RESUME, REFERENCES, and more INFORMATION    ***

Thesis: Geographic Information Systems as a Data Management Tool for
        Sea Floor Mapping.
___________________________________________________________________________
Ocean Mapping Development Center     | gerry at omdc.gso.uri.edu {Internet}
University of Rhode Island           |      voice (401)-792-6768      
Narragansett, RI 02882               |       fax (401)-792-6849
___________________________________________________________________________




More information about the grass-user mailing list