From: <ost...@us...> - 2009-02-25 05:04:09
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Revision: 2302 http://gpsdrive.svn.sourceforge.net/gpsdrive/?rev=2302&view=rev Author: ostertag Date: 2009-02-25 05:03:56 +0000 (Wed, 25 Feb 2009) Log Message: ----------- Move help to a seperate option --help; this helps in map-page creation Modified Paths: -------------- trunk/scripts/gdal_slice.sh Modified: trunk/scripts/gdal_slice.sh =================================================================== --- trunk/scripts/gdal_slice.sh 2009-02-25 04:53:50 UTC (rev 2301) +++ trunk/scripts/gdal_slice.sh 2009-02-25 05:03:56 UTC (rev 2302) @@ -14,48 +14,53 @@ # License (>=v2). Read the file COPYING that comes with # GPSDrive for details. # -############################################################################# -# -# Assumes that the input file is: -# - A format known to GDAL -# - Is georegistered -# - Has minimal convergence angle (true North is directly up). see man page -# -# Requires awk, GDAL tools from gdal.org and NetPBM tools. -# -# Important! The maps must be named "map_*" for UTM-like projections -# (lat:lon = 1:cos(lat)) and "top_*" for lat/lon Plate carree projection -# (lat:lon = 1:1). The prefix is given so that gpsdrive knows how to -# scale the maps correctly. Alternatively the maps can be stored without -# prefix in subdirectories of $HOME/.gpsdrive/ which end in "_map" or -# "_top". To avoid distortion, anything more than 1:150k to 1:500k -# should use "top_*". -# -# Beware if you are using an image originating from a map projection with -# a significant deviation between true north and the map projection's -# local +y direction (known as the Convergence Angle). GpsDrive assumes -# that true north is always directly up! i.e. the Central Meridian of the -# map projection is located at the map tile's center. For some map projec- -# tions and areas of the country this can be a really bad assumption and -# your map will be significantly rotated. This effect is most visible at -# map scales covering a large area. This does not affect lat/lon maps. -# The pnmrotate program may help, or gdalwarp to a custom map-centered tmerc. -# -# To make an overview map, open your GeoTIFF in GIMP, Image->Mode->RGB, -# Image->Scale, 25%, cubic, and save as PNG. Next use gdal_translate -# to re-ref the GeoTIFF. You can also shrink with gdal_translate and -# gdalwarp, but the output isn't as nice. i.e. gdalwarp lets you use -# cubic spline resapmpling (-rcs), which is great for imagery but no -# good for a paletted image like a chart. If using that multiply the -# original resolution by 4 (gdalinfo) and use with the gdalwarp -tr -# option. -# To reapply georef to the GIMP image: -# gdal_translate -a_ullr w n e s -a_srs EPSG:code $FILE.png $FILE.tif -# -############################################################################# if [ $# -lt 1 ] ; then + echo "Usage: $0 <FILENAME.tif> [top|Map] [Png|jpg]" + echo "use $0 --help for detailed Information" + exit 1 +fi + +if echo "$@" | grep -q -e "--help" ; then echo "Usage: gdal_slice_auto.sh <FILENAME.tif> [top|Map] [Png|jpg]" +cat <<EOF + + Assumes that the input file is: + - A format known to GDAL + - Is georegistered + - Has minimal convergence angle (true North is directly up). see man page + + Requires awk, GDAL tools from gdal.org and NetPBM tools. + + Important! The maps must be named "map_*" for UTM-like projections + (lat:lon = 1:cos(lat)) and "top_*" for lat/lon Plate carree projection + (lat:lon = 1:1). The prefix is given so that gpsdrive knows how to + scale the maps correctly. Alternatively the maps can be stored without + prefix in subdirectories of $HOME/.gpsdrive/ which end in "_map" or + "_top". To avoid distortion, anything more than 1:150k to 1:500k + should use "top_*". + + Beware if you are using an image originating from a map projection with + a significant deviation between true north and the map projection's + local +y direction (known as the Convergence Angle). GpsDrive assumes + that true north is always directly up! i.e. the Central Meridian of the + map projection is located at the map tile's center. For some map projec- + tions and areas of the country this can be a really bad assumption and + your map will be significantly rotated. This effect is most visible at + map scales covering a large area. This does not affect lat/lon maps. + The pnmrotate program may help, or gdalwarp to a custom map-centered tmerc. + + To make an overview map, open your GeoTIFF in GIMP, Image->Mode->RGB, + Image->Scale, 25%, cubic, and save as PNG. Next use gdal_translate + to re-ref the GeoTIFF. You can also shrink with gdal_translate and + gdalwarp, but the output isn't as nice. i.e. gdalwarp lets you use + cubic spline resapmpling (-rcs), which is great for imagery but no + good for a paletted image like a chart. If using that multiply the + original resolution by 4 (gdalinfo) and use with the gdalwarp -tr + option. + To reapply georef to the GIMP image: + gdal_translate -a_ullr w n e s -a_srs EPSG:code $FILE.png $FILE.tif +EOF exit 1 fi This was sent by the SourceForge.net collaborative development platform, the world's largest Open Source development site. |