X-Git-Url: https://git.gag.com/?p=debian%2Fsplat;a=blobdiff_plain;f=utils%2FREADME;fp=utils%2FREADME;h=31a9c4d907399d3c61b2a74e29742cebe4b4811e;hp=593a13c7fdfd5276f5cd1f6cdfa3bdcdd7245065;hb=63fe09e1131ae8f451b4a5af9dbae05cb07d529e;hpb=8c97af274a0a0c0f6c949aab5b35731f7b187873 diff --git a/utils/README b/utils/README index 593a13c..31a9c4d 100644 --- a/utils/README +++ b/utils/README @@ -1,34 +1,64 @@ + ================ + SPLAT! Utilities + ================ + Utilities for use with SPLAT! software are found under the -splat-1.1.0/utils directory. They include the following: +splat-1.1.1/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 3-arc second +STS-99 Space Shuttle Topography Mission (SRTM-3) 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-3 +Version 2 elevation models contain data "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 SDF data created through the usgs2sdf utility +(below). If equivalent USGS-derived SPLAT Data Files are 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 +SRTM-3 Version 2 Elevation Data may be downloaded from: -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: + ftp://e0srp01u.ecs.nasa.gov:21/srtm/version2/ - citydecoder pl34 | sort > cities.nj.dat +Files available at this site are ZIP compressed, and must be +uncompressed (using "unzip", or "gunzip -S .zip") prior to being +processed by srtm2sdf. -A list of FIPS codes (fips.txt) is included under splat/utils for your -convenience. +The srtm2sdf utility accepts command-line options as follows: + +-d: used to specify the directory path to the location of existing + SDF files (presumably created at an earlier date through the + usgs2sdf or postdownload utility) 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 replaced. Below this limit, SRTM elevation data is either + replaced using existing SDF equivalent files, 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. usgs2sdf @@ -48,14 +78,44 @@ takes as an argument the name of the gzipped Digital Elevation Model postdownload uncompresses the DEM file, adds necessary record delimiters, 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/utils for your +convenience. + + fontdata ======== The fontdata utility reads Slackware gzipped console font data @@ -106,5 +166,5 @@ You need to be 'root' to install any or all of these utilities. --- John A. Magliacane, KD2BD -January 2004 +March 2006