5 Utilities for use with SPLAT! software are found under the
6 splat-1.2.1/utils directory. They include the following:
11 The srtm2sdf utility generates SPLAT Data Files (SDFs) from 3-arc second
12 STS-99 Space Shuttle Topography Mission (SRTM-3) elevation data files.
13 This data is of a much higher quality than that contained in older USGS
14 Digital Elevation Models of the same resolution. However, many SRTM-3
15 Version 2 elevation models contain data "voids" and "wells" that are the
16 consequence of the radar mapping process.
18 The srtm2sdf utility has the ability to detect and replace SRTM data
19 outliers with equivalent SDF data created through the usgs2sdf utility
20 (below). If equivalent USGS-derived SPLAT Data Files are not available,
21 SRTM outliers are handled either through adjacent pixel averaging, or by
22 threshold limiting using user-specified limits. Of all three methods,
23 the USGS-derived SDF replacement method yields the best results.
25 SRTM-3 Version 2 Elevation Data may be downloaded from:
27 ftp://e0srp01u.ecs.nasa.gov:21/srtm/version2/
29 Files available at this site are ZIP compressed, and must be
30 uncompressed (using "unzip", or "gunzip -S .zip") prior to being
31 processed by srtm2sdf.
33 The srtm2sdf utility accepts command-line options as follows:
35 -d: used to specify the directory path to the location of existing
36 SDF files (presumably created at an earlier date through the
37 usgs2sdf or postdownload utility) that are to be used to replace
38 outliers found in the SRTM data file. The -d option overrides
39 the default path specified in your $HOME/.splat_path file.
41 -n: used to specify the elevation (in meters) below which SRTM data
42 is replaced. Below this limit, SRTM elevation data is either
43 replaced using existing SDF equivalent files, or averaged among
44 adjacent elevation data points. The default threshold for the
45 replacement limit is sea-level (0 meters). Unless elevations
46 below sea-level are known to exist for the region being
47 processed by the srtm2sdf utility, the -n option need not be
50 Some examples of srtm2sdf use:
54 srtm2sdf -d /cdrom/sdf N40W074.hgt
56 srtm2sdf -d /dev/null N40W074.hgt (/dev/null prevents USGS data
57 replacement from taking place)
59 srtm2sdf -n -5 N40W074.hgt
61 In all cases, SDF files are written into the current working directory.
63 The srtm2sdf utility may also be used to convert 3-arc second SRTM data
64 in Band Interleaved by Line (.BIL) format for use with SPLAT! This data
65 is available via the web at: http://seamless.usgs.gov/website/seamless/
67 Once the region of the world has been selected at this site, select the
68 "Define Download Area By Coordinates" button under "Downloads". Proceed
69 to request the download of the region(s) desired in 1 degree by 1 degree
70 regions only, and make sure bounding coordinates entered fall exactly on
71 whole numbers of latitude and longitude (no decimal fractions of a degree).
73 Select the "Add Area" button at the bottom.
75 On the next screen, select "Modify Data Request". On the subsequent screen,
76 de-select the National Elevation Dataset (NED) format and select "SRTM 3 arc
77 sec - Shuttle Radar Topography Mission [Finished]". Change the format from
78 ArcGrid to BIL, and from HTML to TXT.
80 Select the "Save Changes and Return To Summary" button.
82 Select the "Download" button, and save the file once it has been sent to
85 Uncompressing the file will generate a directory containing all files
86 contained within the downloaded archive. Move into the directory and
87 invoke srtm2sdf as described above with the filename having the .bil
88 extension given as its argument. Finally, move or copy the generated
89 .sdf file to your SPLAT! working directory.
94 The usgs2sdf utility takes as an argument the name of an uncompressed
95 and record delimited Digital Elevation Model Data (DEM) downloaded from
96 the US Geological Survey, and generates a SPLAT Data File (SDF) compatible
97 with SPLAT! Software. usgs2sdf may be invoked manually, or via the
103 postdownload is a front-end to the usgs2sdf utility. postdownload
104 takes as an argument the name of the gzipped Digital Elevation Model
105 (DEM) downloaded from the US Geological Survey (ie: wilmington-w.gz).
106 postdownload uncompresses the DEM file, adds necessary record delimiters,
107 and invokes usgs2sdf to produce a SPLAT Data File (SDF).
109 USGS Digital Elevation Models may be downloaded from:
111 http://edcftp.cr.usgs.gov/pub/data/DEM/250/
113 Invoke postdownload with the name of each DEM file downloaded to
114 produce a database of SPLAT Data Files.
119 This utility reads U.S. Census Bureau files of Incorporated Places/Census
120 Designated Places, and generates city/site data files for use with SPLAT!
121 software. Files for use with this utility are available for download
124 http://www.census.gov/geo/www/cob/bdy_files.html.
126 Please select the ARC/INFO Ungenerate (ASCII) Metadata Cartographic Boundary
127 Files from this site and unzip them prior to importing them to citydecoder.
128 U.S. Census files are cataloged by the two digit FIPS code for the region
129 (state) they represent. citydecoder takes as an argument the two-letter
130 file prefix plus the FIPS code of the region or state being processed.
135 reads files "pl34_d00.dat" and "pl34_d00a.dat" that are extracted after
136 the downloaded file has been unzipped, and generates a list of city names
137 and geographical coordinates for the state of New Jersey (FIPS code 34).
138 This data may be sorted and written to a file (cities.nj.dat) in the
141 citydecoder pl34 | sort > cities.nj.dat
143 A list of FIPS codes (fips.txt) is included under splat/utils for your
149 The fontdata utility reads Slackware gzipped console font data
150 to create the fontdata.h file required for compilation of SPLAT!.
151 Font data of the type needed by this utility may be found under
152 /usr/lib/kbd/consolefonts (Slackware < 8), or under
153 /usr/share/kbd/consolefonts (Slackware >= 8.0).
155 A default fontdata.h file is already included in with SPLAT!, and is
156 a derivative of the s.fnt console font type available under Slackware.
157 fontdata takes as an argument the name of the file containing the
158 gzipped compressed console fonts:
163 Building The Utilities
164 ======================
165 Normally, these utilities are built and installed along with SPLAT!
166 when SPLAT!'s ./configure script is invoked. However, if you modify
167 them and/or wish to build and install them separately, here is how it's
168 done. First, invoke the "build" script to compile each or all utilities
169 in this directory by name. For example:
173 compiles citydecoder only, while
177 compiles all utilities.
180 Installing The Utilities
181 ========================
182 Invoke the "install" script to install each or all utilities in this
183 directory by name. For example:
185 ./install citydecoder
187 installs citydecoder only, while
191 installs all utilities.
193 You need to be 'root' to install any or all of these utilities.
196 John A. Magliacane, KD2BD