+ ================
+ SPLAT! Utilities
+ ================
+
Utilities for use with SPLAT! software are found under the
-splat-1.1.0/utils directory. They include the following:
+splat-1.3.0/utils directory. They include the following:
-citydecoder
-===========
-This utility reads U.S. Census Bureau files of Incorporated Places/Census
-Designated Places, and generates city/site data files for use with SPLAT!
-software. Files for use with this utility are available for download
-free of charge from:
- http://www.census.gov/geo/www/cob/bdy_files.html.
+srtm2sdf
+========
+The srtm2sdf utility generates SPLAT Data Files (SDFs) from STS-99
+Space Shuttle Topography Mission (SRTM) elevation data files. This
+data is of a much higher quality than that contained in older USGS
+Digital Elevation Models of the same resolution. However, many SRTM
+Version 2 elevation models contain data "spikes", "voids", and "wells"
+that are the consequence of the radar mapping process.
-Please select the ARC/INFO Ungenerate (ASCII) Metadata Cartographic Boundary
-Files from this site and unzip them prior to importing them to citydecoder.
-U.S. Census files are cataloged by the two digit FIPS code for the region
-(state) they represent. citydecoder takes as an argument the two-letter
-file prefix plus the FIPS code of the region or state being processed.
-For example:
+The srtm2sdf utility has the ability to detect and replace SRTM data
+outliers with equivalent usgs2sdf derived SDF data (see usgs2sdf below).
+If such data is not available, SRTM outliers are handled either through
+adjacent pixel averaging, or by threshold limiting using user-specified
+limits. Of all three methods, the USGS-derived SDF replacement method
+yields the best results.
- citydecoder pl34
+The srtm2sdf utility processes SRTM-3 3-arc second resolution data
+or use with SPLAT! operating in standard definition mode.
-reads files "pl34_d00.dat" and "pl34_d00a.dat" that are extracted after
-the downloaded file has been unzipped, and generates a list of city names
-and geographical coordinates for the state of New Jersey (FIPS code 34).
-This data may be sorted and written to a file (cities.nj.dat) in the
-following manner:
+SRTM-3 Version 2 Elevation Data files may be downloaded from:
- citydecoder pl34 | sort > cities.nj.dat
+ ftp://e0srp01u.ecs.nasa.gov:21/srtm/version2/
+
+Files available at this site are ZIP compressed, and must be
+uncompressed (using "unzip", or "gunzip -S .zip") prior to being
+processed by srtm2sdf.
+
+The srtm2sdf utility accepts command-line options as follows:
+
+-d: used to specify the directory path to the location of usgs2sdf
+ derived SDF files that are to be used to replace outliers found
+ in the SRTM data file. The -d option overrides the default path
+ specified in your $HOME/.splat_path file.
+
+-n: used to specify the elevation (in meters) below which SRTM data
+ is either replaced with usgs2sdf-derived SDF data, or averaged
+ among adjacent elevation data points. The default threshold for
+ the replacement limit is sea-level (0 meters). Unless elevations
+ below sea-level are known to exist for the region being
+ processed by the srtm2sdf utility, the -n option need not be
+ specified.
+
+Some examples of srtm2sdf use:
+
+ srtm2sdf N40W074.hgt
+
+ srtm2sdf -d /cdrom/sdf N40W074.hgt
+
+ srtm2sdf -d /dev/null N40W074.hgt (/dev/null prevents USGS data
+ replacement from taking place)
+
+ srtm2sdf -n -5 N40W074.hgt
+
+In all cases, SDF files are written into the current working directory.
+
+The srtm2sdf utility may also be used to convert 3-arc second SRTM data
+in Band Interleaved by Line (.BIL) format for use with SPLAT! This data
+is available via the web at: http://seamless.usgs.gov/website/seamless/
+
+Once the region of the world has been selected at this site, select the
+"Define Download Area By Coordinates" button under "Downloads". Proceed
+to request the download of the region(s) desired in 1 degree by 1 degree
+regions only, and make sure bounding coordinates entered fall exactly on
+whole numbers of latitude and longitude (no decimal fractions of a degree).
+
+Select the "Add Area" button at the bottom.
+
+On the next screen, select "Modify Data Request". On the subsequent screen,
+de-select the National Elevation Dataset (NED) format and select "SRTM 3 arc
+sec - Shuttle Radar Topography Mission [Finished]". Change the format from
+ArcGrid to BIL, and from HTML to TXT.
-A list of FIPS codes (fips.txt) is included under splat/utils for your
-convenience.
+Select the "Save Changes and Return To Summary" button.
+
+Select the "Download" button, and save the file once it has been sent to
+your web browser.
+
+Uncompressing the file will generate a directory containing all files
+contained within the downloaded archive. Move into the directory and
+invoke srtm2sdf as described above with the filename having the .bil
+extension given as its argument. Finally, move or copy the generated
+.sdf file to your SPLAT! working directory.
+
+
+srtm2sdf-hd
+===========
+The srtm2sdf-hd utility operates in an identical manner as srtm2sdf,
+but is used to generate HD SDF files from SRTM-1 one-arc second
+resolution data files for use with SPLAT! HD. SRTM-1 data files
+are available for the United States and its territories and
+possessions, and may be downloaded from:
+
+ ftp://e0srp01u.ecs.nasa.gov:21/srtm/version2/SRTM1/
usgs2sdf
takes as an argument the name of the gzipped Digital Elevation Model
(DEM) downloaded from the US Geological Survey (ie: wilmington-w.gz).
postdownload uncompresses the DEM file, adds necessary record delimiters,
-and invokes usgs2sdf to produce a SPLAT Data File (SDF).
+and invokes usgs2sdf to produce a SPLAT! Data File (SDF).
-Digital Elevation Models may be downloaded from:
+USGS Digital Elevation Models may be downloaded from:
- http://edcsgs9.cr.usgs.gov/glis/hyper/guide/1_dgr_demfig/index1m.html
+ http://edcftp.cr.usgs.gov/pub/data/DEM/250/
Invoke postdownload with the name of each DEM file downloaded to
produce a database of SPLAT Data Files.
+citydecoder
+===========
+This utility reads U.S. Census Bureau files of Incorporated Places/Census
+Designated Places, and generates city/site data files for use with SPLAT!
+software. Files for use with this utility are available for download
+free of charge from:
+
+ http://www.census.gov/geo/www/cob/bdy_files.html.
+
+Please select the ARC/INFO Ungenerate (ASCII) Metadata Cartographic Boundary
+Files from this site and unzip them prior to importing them to citydecoder.
+U.S. Census files are cataloged by the two digit FIPS code for the region
+(state) they represent. citydecoder takes as an argument the two-letter
+file prefix plus the FIPS code of the region or state being processed.
+For example:
+
+ citydecoder pl34
+
+reads files "pl34_d00.dat" and "pl34_d00a.dat" that are extracted after
+the downloaded file has been unzipped, and generates a list of city names
+and geographical coordinates for the state of New Jersey (FIPS code 34).
+This data may be sorted and written to a file (cities.nj.dat) in the
+following manner:
+
+ citydecoder pl34 | sort > cities.nj.dat
+
+A list of FIPS codes (fips.txt) is included under splat-1.3.0/utils
+for your convenience.
+
+
fontdata
========
The fontdata utility reads Slackware gzipped console font data
fontdata s.fnt.gz
+bearing
+=======
+The bearing utility reads a pair of .qth files specified on the command
+line, and returns the azimuth bearing and great circle path distance between
+the two points specified. A -metric switch is available so that distances
+can be provided in kilometers rather than statute miles. SPLAT! provides
+similar distance and bearing information between two specific site locations.
+The bearing utility, however, provides the information quickly and easily
+over great distances without having to run SPLAT!
+
+
Building The Utilities
======================
Normally, these utilities are built and installed along with SPLAT!
---
John A. Magliacane, KD2BD
-January 2004
+August 2008
projects / debian / splat / blobdiff