[FWTools] Help with LCC georeferencing and reprojection

James Trimble jimmit.t at gmail.com
Thu Oct 9 12:54:28 EDT 2008


** I apologize if this message appears more than once, but it does not look
like it's going through for me **

Hi, I am trying to georeference and reproject an FAA Enroute IFR chart.  You
can find the pdf version of this chart at
http://www.jamestrimble.info/US<http://goog_1223485636161/> L32
31 JUL 08.pdf
<http://www.jamestrimble.info/US%20L32%2031%20JUL%2008.pdf>

I use The Gimp to convert the pdf to png.

The parameters are
L-32  1:14NM (1020787)
GP 47 56 09.6N 063 04 30.3W (Upper Right)
GP 46 02 46.4N 079 29 47.0W (Upper Left)
GP 41 48 34.9N 078 00 33.5W (Lower Left)
GP 43 35 36.2N 062 37 08.3W (Lower Right)

Top Standard Parallel 45 00 00N
Bottom Standard Parallel 33 00 00N
Central Meridian 95 00 00W
Origin 39 00 00N 95 00 00W

Datum = North American Datum of 1983

Ultimately, I'd like to have this map in a mercator projection to overlay
with google maps.

The commands I tried to use are :

gdal_translate -a_srs "+proj=lcc +lat_1=45.0 +lat_2=33.0 +lat_0=39.0
+lon_0=95.0 +datum=NAD83" -a_ullr -79.4964 46.0462 -62.6190 43.5934 -of
GTiff -co "INTERLEAVE=PIXEL" "C:\Documents and Settings\James\Desktop\US L32
31 JUL 08_CROPPED.png" .\USL32.tiff

gdalwarp -of GTiff -co "INTERLEAVE=PIXEL" -s_srs "+proj=lcc +lat_1=45.0
+lat_2=33.0 +lat_0=39.0 +lon_0=95.0 +datum=NAD83" -t_srs "+proj=merc
+datum=NAD83" .\USL32.tiff .\USL32_MERC.tiff

I would really appreciate some help on how to do this correctly.

Thank you very much,
James
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.maptools.org/pipermail/fwtools/attachments/20081009/50145594/attachment.html


More information about the FWTools mailing list