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Programming Technology

GPS Toolkit (GPSTk) 1.0 Released 197

Posted by michael
from the you-are-here dept.
rmach writes "Based on many years of work performed at ARL:UT, we have release GPSTk under the GNU LGPL. GPSTk is a cross platform library and set of applications that provides both fundamental and advanced GPS processing algorithms to the GPS and open source community. A wide array of functions are provided by the GPSTk library, including: RINEX I/O, ephemeris calculation, P-code generation, atmospheric refraction models, and positioning algorithms. GPSTk applications provided more concrete benefits to the user, including: cycle slip detection and removal, calculation of the Total Electron Content (TEC) of the ionosphere, position residual computation, and RINEX file manipulation. The library is about 41,000 SLOC with a COCOMO estimated cost to develop of about $1.3 million. You can also read more about it in the current issue (September '04) of Linux Journal."
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GPS Toolkit (GPSTk) 1.0 Released

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  • by Anonymous Coward on Tuesday August 17, 2004 @02:07PM (#9994077)
    ... I don't even remotely understand what this post is about. ARLUT? RINEX? cycle slip detection? TEC? SLOC? COCOMO?
    • by Espectr0 (577637) on Tuesday August 17, 2004 @02:16PM (#9994175) Journal
      SLOC means source lines of code. COCOMO (construction code model) is the name of a method used to estimate costs of development, mostly in person-months needed to finish a project.
      • by LesPaul75 (571752) on Tuesday August 17, 2004 @02:43PM (#9994447) Journal
        No, it's not just you...

        ARL:UT GPSTk GNU LGPL GPS RINEX I/O P-code TEC SLOC COCOMO

        I thought the article was one of those crypto-quotes from the newspaper. I solved it, and it translates to

        CATS:YOU HAVE NO CHANCE TO SURVIVE MAKE YOUR TIME

        Pretty scary, if you ask me.
        • No, it's not just you...

          ARL:UT GPSTk GNU LGPL GPS RINEX I/O P-code TEC SLOC COCOMO

          I thought the article was one of those crypto-quotes from the newspaper.

          The scary thing was that I didn't notice because I actually understood most of the abbrevs. Did I now pass my slashdot-exam?

      • I wonder how they estimate the cost of development when you find this in the code [sourceforge.net]?

        00231 // This code "stolen" from Sven Reifegerste (zorci@gmx.de).
        00232 // Found at http://rcswww.urz.tu-dresden.de/~sr21/crctester.c
        00233 // from link at http://rcswww.urz.tu-dresden.de/~sr21/crc.html

        Isn't Sven more expensive than a student? And how can they release it under the LGPL with "stolen" code? :P
    • All about RINEX: http://www.ngs.noaa.gov/CORS/instructions2/ Cycle slipping is explained here: http://www.gmat.unsw.edu.au/snap/gps/gps_survey/ch ap7/735.htm
    • Oh, and ARL:UT is here: http://www.arlut.utexas.edu/ It's Texas university's applied research lab. Use the google, dude :)
    • I don't even remotely understand what this post is about.

      Not to worry... This is just an old tried & true method of exposition wherein the author deliberately tries to mystify the reader by obfuscating the subject as much as possible. By doing this, (s)he hopes to appear much more knowledgable than is actually the case, and certainly more so than the reader.The library is about 41,000 SLOC with a COCOMO estimated cost to develop of about $1.3 million.

      I rest my case. Don't just say it's "41,000 lines o

    • They've released software that translates the raw GPS satellite data into corrected, useful coordinates (e.g. latitude/longitude) in a variety of mapping systems. These are the calculations that are done inside a typicall GPS unit. Unless you are building a homebrew GPS receiver, you probably don't need it.
  • by Anonymous Coward on Tuesday August 17, 2004 @02:07PM (#9994080)
    anyone that has worked with GPS and GIS data know the real hard part is fixing and processing all the data. Getting the data into a database in a normalized format is perhaps one of the most challenging parts of building a gps/gis application. luckily companies like NavTech provide good data that is supplemented with their own surveys.
  • by skroz (7870) on Tuesday August 17, 2004 @02:07PM (#9994084) Homepage
    So, uh, like... does this mean I can find a geocache faster?
  • by k4_pacific (736911) <k4_pacificNO@SPAMyahoo.com> on Tuesday August 17, 2004 @02:07PM (#9994085) Homepage Journal
    Just the other day, I was trying to find a way to calculate the total electron content of the ionosphere.
    • I've already patented my process for calculating the total electron content of the ionosphere. It's very simple and ingenious. Count them.

      Sure hope this doesn't infringe. I'd really hate to have to charge you all $699 to use it.
  • by Anonymous Coward on Tuesday August 17, 2004 @02:08PM (#9994097)
    I'm still not gonna stop and ask for directions.
  • I applied for a job at Applied Research Laboratories back in 1997. The job was writing C++ code for a SONAR system, something to do with dolphins. Very cool stuff for the Defense Department. I'm not surprised to see this toolkit come out of ARL.

    UT Austin has some awesome engineers. Hook 'em Horns!

  • Track editing? (Score:5, Interesting)

    by Hanna's Goblin Toys (635700) on Tuesday August 17, 2004 @02:12PM (#9994135) Homepage Journal
    When I bought my Garmin Etrex, I wanted to use it to store mountain bike rides and overlay them with maps. Easy, right? Bah! I spent two weeks trying to find a way to do this on my Linux box before giving up. I ended up paying out of my rear end to buy expensive Garmin maps and closed source software. Even then, I couldn't mix and match tracks, let alone cut and paste sections of them together to make trail maps.

    The other featuer I've always wanted is to do profile slices of my rides to see climbing and descending rates, especially during races.

    All in all this toolkit sounds hugely promising, as the last time I looked at SF.net/Freshmeat the capabilities were nearly nil. All I want is a simple import module, track overlay over free downloadable maps, and a track editor...

    I'm going to be spending the evening trying to get this stuff working, hopefully it will provide a replacement to my current Garmin/Microsoft solution!
    • Re:Track editing? (Score:2, Interesting)

      by HighBit (689339)
      I actually have a HOWTO [lost-habit.com] on this...

      I also have an (alpha-quality) script that actually automates making maps from gps data (using kismet)... maybe someday I'll get off my ass and finish it..
    • Re:Track editing? (Score:3, Informative)

      by rjstanford (69735)
      I highly recommend TopoFusion [topofusion.com]. No relationship other than a very satisfied customer. I got the free version, but paid the very reasonable $40 within a couple of days. Really good software and a very responsive developer.
    • I'm in the same boat!

      However, I did find this site...

      http://nationalatlas.gov/

      That allows you to download maps plus all the info about them.

      What I'd like to write is something like "map point" for linux.

      This way I can take my laptop on the road and not having to install windows on it.
    • GPS tends to not track vertical changes easily with standard deviation as much as +/- 1000 ft. That's probably why the routes on my garmin V GPS doesnt show vertical changes. It's too inaccurate for normal use. A calibrated altimeter will probably do a better job. I think they now have recent GPS combined with altimeter.
      • I think they now have recent GPS combined with altimeter.

        There are several. I'm only really familiar with Garmin's products, but I can tell you that the high end of their eTrex line has an integrated compass and altimeter, and their newish GPSMap 60CS has them as well. I own two of the former and one of the latter (long story), and they're great devices and provide pretty accurate altitude data (seems to be within about 10 feet, assuming the weather hasn't changed recently and the device has had some t

        • The auto-callibration on the 60CS using GPS data ain't that great. I callibrated mine at the local private airport (accurate data for both altitude and barometric pressure,) drove to my house a few miles away, and set the GPSr in the window. Everything was good for a few days, with only very small variations in altitude. But when the next storm front moved in, it was all over. Afterwards the recorded altitude varied by 100 feet or more over the next day. I then callibrated it again at the airport and a
          • Interesting. Mine has been much more consistent. At home I always get within 10-15 feet if I let the device sit out under the open sky for a couple of hours.

            I guess "always" has only been a half-dozen times. Maybe I've just been lucky?

          • Actually I use this to my advantage, if the altitude from the altimeter starts changing rapidly then I know a storm is coming =) Comes in rather usefull when mountain climbing.
      • Assuming that you're traveling near the surface of the earth:

        1) The receiver can use that information as a constraint to the solution of position
        2) You can safely assume that you're at about the same height as the underlying map says.

        This is, of course, assuming that you have a map to correlate with, and that the receiver does so.

        Even if the receiver doesn't use the useful map information, the software you use -should- be able to tell you the height at any particular X,Y position. (Its not a hard calcula
      • GPS tends to not track vertical changes easily with standard deviation as much as +/- 1000 ft.

        I agree -- it's inaccurate -- but it's not anywhere near that bad. +/- 100 feet seems much more reasonable.

        A calibrated altimeter will probably do a better job.

        Just probably? :)

        Good altimeters are much more accurate than this. Accuracy of +/- one meter is pretty common nowadays, and this is for a unit the size of a watch. Pretty amazing ...

        I think they now have recent GPS combined with altimeter.

    • Re:Track editing? (Score:5, Informative)

      by swillden (191260) * <shawn-ds@willden.org> on Tuesday August 17, 2004 @02:37PM (#9994388) Homepage Journal

      I spent two weeks trying to find a way to do this on my Linux box before giving up. I ended up paying out of my rear end to buy expensive Garmin maps and closed source software. Even then, I couldn't mix and match tracks, let alone cut and paste sections of them together to make trail maps.

      Depending on exactly what you want to do, there are some in-progress Linux tools that are usable. gpsbabel is a tool that can convert track, route and waypoint files to and from a bunch of different file formats, including the Garmin MapSource files. Some of the file formats are text, so you can do pretty much anything you like by converting to one of those, munging the stuff with your favorite utilities and scripting language, and converting back to MapSource (or whatever).

      For visualization and tracking, check out gpsdrive. You can download maps for it from various on-line sites. Rick Richardson's geo-* tools are a bunch of useful bash and (I think, haven't looked lately) perl scripts that do lots of useful things, like making it easy to download maps and stuff. Most of Rick's stuff is focused on geocaching (for which it's really great, BTW, especially in conjunction with gpx2html.

      The other feature I've always wanted is to do profile slices of my rides to see climbing and descending rates, especially during races.

      I don't know of anything to do this (maybe someone else does?) but if you're a programmer hacking it together yourself wouldn't be too hard, given gpsbabel to convert the data into a mungeable format so you can get the times, positions and altitudes (and I think Rick's code has some stuff for calculating distances).

      All in all this toolkit sounds hugely promising, as the last time I looked at SF.net/Freshmeat the capabilities were nearly nil. All I want is a simple import module, track overlay over free downloadable maps, and a track editor...

      I don't think this toolkit is what you're looking for. Oh, I forgot to mention, look at gpstrans for transferring data between your Vista and Linux. Works fine, and you don't have to use gpsbabel to get the data in a usable format.

      • No I don't thik this is what he needs either but the guy who writes what he needs could use this!
      • Re:Track editing? (Score:3, Informative)

        by parkrrrr (30782)

        Oh, I forgot to mention, look at gpstrans for transferring data between your Vista and Linux. Works fine, and you don't have to use gpsbabel to get the data in a usable format.

        Depending on what your definition of "a usable format" is, and keeping in mind that GPSBabel [sourceforge.net] has some built-in customization for whatever your favorite xSV file format may be, why not just do gpsbabel -i garmin -f /dev/tty00 -o [your-favorite-file-format] -F [filename] and do everything in one step?

        Not that this has anything

      • Re:Track editing? (Score:2, Informative)

        by jfurtner (681531)

        Something like GPSMan [ncc.up.pt] will overlay over maps, download from the GPS, and show climb/descent rates and speeds over time and distance, but doesn't download them itself - you have to download and then georeference maps manually (or use a map that's already been referenced).

        Written in Tk/Tcl, so it runs on Linux/OSX/Windows/anywhere you can run Tk/Tcl. It's what I've been using since I got a Foretrex. Just a sastified customer..

        My problem is most of the free map sites I've found are only relevant to the US

    • Re:Track editing? (Score:2, Informative)

      by Anonymous Coward
      You can use Radio Mobile [cplus.org] to create the maps. It is designed to calculate radio frequency coverage based on terrain information, but it can be "abused" to create nice maps with different ways of displaying altitude, which is a very nice feature if you're planning bike rides. It also allows you to automatically fetch and overlay maps from MapQuest, MapPoint, Toporama and Terraserver. These maps can then be exported and used in programs like OziExplorer [oziexplorer.com] (shareware) or GPS Trackmaker [gpstm.com] (freeware), both of which
    • I bought a Magellan GPS for the sole purpose of hiking around Acadia National Park, and keeping track of my hikes as well as where I took specific pictures.

      Even though I have all that data, it is not in a usable format and it seems to be a real chore to get it into one. I would love to be able to just take the data from the GPS unit and display it on any of several open source mapping packages, but the possibilities just sren't there yet.

      This is an excellent step in the right direction!
    • Re:Track editing? (Score:5, Informative)

      by garcia (6573) * on Tuesday August 17, 2004 @02:50PM (#9994514)
      GPS Visualizer [gpsvisualizer.com]. This site is free and uses SVG to display maps. You can overlay GPX/LOC or track data (among others) over top of maps.
    • Take a look at this option:

      www.gpstm.com [gpstm.com]

      It's not open source, but at least its free (the professional version is the one intended for cartographers)

      The interface could improve a bit, but you get used to it
    • When I bought my Garmin Etrex, I wanted to use it to store mountain bike rides and overlay them with maps.

      Dave Wissenback's free program [cableone.net] "allows you to plan and record your hiking and mountain bike trips with a Garmin eTrex GPS receiver and share your local knowledge of trails with others. You can also use the program to print topographic maps with these trails, either on a single page or as a mosaic on many sheets of paper. And you can use the program to visualize planned or past trips in 3D by virtu

    • This is slightly OT, but....

      Is there any linux based mechanism to find automobile routes and give directions based on GPS feedback? I'm willing to buy software and or data, and put time into it.

      I'm building up to putting a PC in the car for multiple purposes, and I'd like navigations tools to be one of them. Perferrably something that works just as well as the dedicated systems you can buy.
    • Take a look at this package from sourceforge...

      http://flighttrack.sourceforge.net/

      Hope this might help....

  • by ylikone (589264) on Tuesday August 17, 2004 @02:19PM (#9994208) Homepage
    If you use a GPS for geocaching, there is already a set of GPS tools for the Linux user here [rkkda.com].
  • by tao_of_biology (666898) <tao.of.biology@gm a i l . c om> on Tuesday August 17, 2004 @02:20PM (#9994213)
    It's amazing what guys are willing to go through to avoid getting out of the damn car and asking for directions. ;)
    • Buying all this GPS gear *IS* asking for directions. What's worse, it's like asking prematurely.

      Merely downloading this is an admission, now and forever, that one does not know where he is, where he is going, or how to get there.
  • by Reorax (629666) on Tuesday August 17, 2004 @02:32PM (#9994328)
    "Based on many years of work performed at ARL:UT"

    Advanced Research Labs: Unreal Tournament?

  • by Anonymous Coward on Tuesday August 17, 2004 @02:39PM (#9994408)
    While I salute and thank the developers here for what looks like may be a useful and valuable package, I just downloaded the library and can see that we're off to a rather bad start.

    Unfortunately, the whole build process requres "jam" (a tool from perforce.com). Arrrgghh!

    That they are using Perforce is a very bad sign. The whole Perforce system is designed by people who didn't understand basic mathematics (as in Set theory), and consequently it's annoying as heck to use.

    Give me BitKeeper or Sun's Teamware (if you have a golden key, and can by-pass the license restrictions) anyday. Or even CVS in a pinch.

    But requiring Jam in a distribution? Have these folks never, ever heard of "configure" and autoconf?

    Hopefully the rest of the code exhibits some technical cluefulness. But right now, I can see that we're off to a bad start.

    To the developers: sorry to give you folks a hard time here, but someone really has to on this.
    • by rmach (164119) * on Tuesday August 17, 2004 @04:27PM (#9995499)
      I agree with your critique. However, this code was extract from various projects using "jam" and there was not time/resources to do anything different. We may consider a change for the future and would welcome any community submissions that would improve the build process.
    • Seriously. Ever try to cross-compile a package that uses configure to build? Yes, you usually use "CC=whatever-gcc configure --target=whatever --host=whatever --build=somethingelse", and that works some of the time. But sometimes the configure scripts use a thing called TRY_RUN[...], which compiles a test program and tries to run it on the build machine (which will fail since it's the wrong architecture). Usually, if you're cross-compiling to a system that is similar to your build computer (e.g., Linux
  • by n2rjt (88804) on Tuesday August 17, 2004 @02:40PM (#9994421) Journal
    I have a few of these:

    GPS = global positioning system (but you knew that)

    ephemeris calculation = modeling a satellite's orbit based on a handful of numbers, demonstrated by http://ssd.jpl.nasa.gov/eph_help.html [nasa.gov]

    RINEX = Receiver Independent Exchange Format, http://www.ngs.noaa.gov/CORS/Rinex2.html [noaa.gov]

    SLOC = source lines of code .. a simplistic and rather poor metric used to gauge the effort required to develop software. http://www.dwheeler.com/sloc/ [dwheeler.com]

    COCOMO = an obsolete software development cost model http://www.jsc.nasa.gov/bu2/COCOMO.html [nasa.gov]

    • ARL:UT -- Applied Research Labs, the University of Texas at Austin. They did a lot of government work (at least when I worked there). Hence the fondness for metrics and LOA (Lots Of Acronyms).

  • ...now can someone give me the location of ARL:UT preferably in sexadecimal?

  • Great! But.... (Score:2, Interesting)

    by dannyelfman (717583)
    What hardware can I use this with?
    • Re:Great! But.... (Score:2, Informative)

      by rmach (164119) *
      You can use these processing routines with any hardware that provides access to the "raw" GPS data (range, phase, etal.). All GPS receivers aimed at the survey market allow this including units from Thales, Trimble, Allan Osborne, and others.
  • In the GPS system, there are three kinds of codes: C/A code, P-code and Y-code.

    Now last I checked the Precision (P) code was considered classified. Details about how this code was generated and how to decrypt it were considered military secrets.

    I don't believe the P-code has anything to do with selective availability either, I think that the P-code is used for the militaries PPS, which is "precise positioning system".

    Anyway, so how is that included in this suite? and further, what purpose does it serve t
  • by eufreka (793009) on Tuesday August 17, 2004 @02:55PM (#9994574)
    Read this http://gpstk.sourceforge.net/getting-started.html [sourceforge.net]

    Check out item 4 (emphasis added):

    You should know your way around a command line or terminal. For UNIX users, this is a given. For Windows users, using the command line (referred to as "DOS prompt" sometimes) may be a challenge.

    Ouch!

  • LGPL! (Score:5, Insightful)

    by rumblin'rabbit (711865) on Tuesday August 17, 2004 @03:01PM (#9994647) Journal
    Lord be praised, it's under the LGPL. This means corporations can use the package in their software, and have the resulting applications delivered externally, without having to make all of their source in the program publicly available. If it were released under the (full) GPL, the package would find much more limited use.

    Root-Mean-Square (ie, Richard Stallman) won't like it, of course. The FSF strongly recommends all software be under the GPL, not the LGPL. Myself, I think that's a serious mistake. Private enterprise is not, and never has been, the enemy. It's particularly a mistake when you want a package to become a de facto standard, and then do your best to ensure the private sector can't use it.

    I thought I would introduce some politics into what is a rather boring technical /. post.

  • What this is (Score:5, Interesting)

    by thule (9041) on Tuesday August 17, 2004 @03:02PM (#9994661) Homepage
    Please correct me if I'm wrong, but this software is very important. This is the software that normally runs inside the GPS, not for drawing maps, but interpreting the GPS radio signals and calculating the lat/long numbers. Why would this be useful? Well, say, you take a project like GnuRadio and make your own GPS receiver. GnuRadio can demodulate the signals and convert it to data. This software would allow you to take the data you receive with GnuRadio and do something with it.

    It seems to me that this is first time that code like this has ever been published under an open license.
    • How about an all-in-one GNURadio project? Broadband RF frontend and tuner, able to:

      -Listen to shortwave to FM broadcasts
      -Watch slow-scan TV
      -Decode RTTY, morse, weatherfax, etc...
      -Decode and output GPS data

      All in a box like this:
      http://www.mini-box.com/m100.htm

      • Or, even more practical/useful (also taking advantage of transmitting hardware):

        - GSM so I can make phone calls
        - broadcast TV so I can watch TV (and ATSC/HDTV while we're at it)
        - WiFi so I can get online
        - X10 so I can control my lights and appliances
        - Keyless entry system so I can warm up my car
        - Garage door opener
        - Bluetooth and/or wireless USB so I can interact with peripherals

        Give it another decade or two and we can have all of this on one mega-PDA.
        • The problem with that is certification (or lack thereof). Demodulating a signal is (almost) always legal but broadcasting with an uncertified device is often not legal.
    • um, no. (Score:2, Informative)

      by SuperBanana (662181)
      Well, say, you take a project like GnuRadio and make your own GPS receiver.

      GPS depends upon measuring the time it takes radio signals to travel less than a meter or two. That's not possible without very specialized electronics. Furthermore- GPS units, at least the kind -you- can buy for a few hundred dollars, don't do any of this bull. They just use WAAS- aka broadcast-via-satellite DGPS.

      Sorry to burst your bubble, but not everything can be done in software.

      • Re:um, no. (Score:3, Interesting)

        by thule (9041)
        Really? What about these projects then:

        GPS and GnuRadio [comsec.com]

        and

        OpenSourceGPS [earthlink.net]

        The latter claims:

        "The receiver requires at a minimum a 100 MHz 486 IBM PC with 640k RAM."

        So it seems to be possible. Someone posted the GPSTk link to the GnuRadio mailing list with the hope of eventually getting GnuRadio the ability to do advanced processing of GPS signals.

        I'm not a GPS expert... am I missing something here?
  • by Anonymous Coward on Tuesday August 17, 2004 @03:18PM (#9994819)
    What would be a "killer app" for me would be a OSS tool to do terrain elevation modeling using DTED/DEM/SDTS datasets to do radio network modeling including radio path profiling, LOS profiles including fresnel zone projection. Given GPS coordinates, antennae elevations above ground level (AGL), and frequency and polarization of the radio signal the tool should be able to give path length, azimuth, verticle declination, freznel zone intrusion, etc.

    Two so-called "free-ware" (as in cost, not OSS!) that I have used are MicroDEM/Terrabase from Prof. Peter Guth of the Oceanography Department, U.S. Naval Academy http://www.usna.edu/Users/oceano/pguth/website/mic rodem.htm/ [usna.edu] and Radio Mobile http://www.cplus.org/rmw/english1.html/ [cplus.org] by Roger Coudé VE2DBE. Both programs have some powerful features, BUT...

    The problems I have with both of the programs:
    1) Buggy
    2) Windows Only
    3) Not OSS
    4) Poor/inconsistent UI

    Unfortunately, both of these programs appear to be written by folks who have much more skill/knowledge about the subjects (GIS and radio telemetry) than they do about programming.

    If they would only release the code under an OSS licensing scheme, perhaps others (professional SW developers?) could clean up (rewrite?) and improve/expand the capabilities. And we could have cross-platform availability to boot!
    • Oddly enough, a project exists at ARL that does exactly that. If you feel like reading about it, look at http://sgl.arlut.utexas.edu/ [utexas.edu].

      I don't think it's closed source, but since I'm working on it, it never really seems closed or open to me :-P. The problem isn't that we don't want it to be open, it's that the propagation models aren't written in house, and they're all closed.
  • by IronChefMorimoto (691038) on Tuesday August 17, 2004 @03:46PM (#9995122)
    Finally -- a means of writing the software required for my GPS-guided canine shock collar defecation system. Now I can just turn the dog loose and not have to worry about her pooping in a different place every time she gets her dump on.

    Shit on the driveway? SHOCK!

    Crap in the neighbor's yard? SHOCK!

    Crap in mean neighbor's yard? NO SHOCK! (subroutine for OPTIONAL shit locations).

    Poop near the mailbox? SHOCK!

    Drop a deuce in the back corner of the yard near all the other piles of shit? NO SHOCK!

    (C) Copyright 2004 by IronChefMorimoto Pet Waste Management Technologies

    IronChefMorimoto

  • by Doc Ruby (173196) on Tuesday August 17, 2004 @05:44PM (#9996106) Homepage Journal
    What about the DGPS (Differential GPS) in our mobile phones that provide E911 (Enhanced 911) emergency phone service? IBM has mentioned an "Engine 18" that lets these superlight GPS receivers send their raw received data to a server for location processing. My Treo 600, with PalmOS5, is really spiffy. Is GPS another demand generator for smartphone Linux?
    • I think you mean A-GPS (Assisted GPS).

      That is what is in some of the E911 phones. IIRC it is only needed for Phase II of E911.

      Some of the phones (mostly Motorola iDEN phones) have full GPS receivers in them so they can work off the cell network too.
      • Yep, AGPS. The cheap, slow AGPS chip gets some GPS data, sends it over the phone's Net connection to a server. That server processes the data, generates the GPS coordinates, and returns it to the phone. The full GPS receivers aren't found in the smartphones, like my T600, because they're too expensive and powerhungry compared with the other features already crowding the phone. So AGPS processing would work with my hardware right now.
  • But while we are at it...

    I live in Quebec and my father lives up north in abitibi. He is a river kayak enthusiast and has been looking for a while for a software which could help him trace route (no pun) that he could navigate on acros the province (and north Ontario also).

    Is there any software or gadget which does the same thing as an in car gps unit (displaying roads on it or printing maps) but for lakes and rivers? Anf if something like this exist, do maps exists to feed to it also?

    Im not really
    • Well GPS is GPS whether you're on a road or a lake. And GPS was big with boaters long before they could make them small enough to fit in your hand. The only question is if there are map products for that area. Browse around the marine sections of Garmin [garmin.com] and Magellan [magellangps.com]. You'll probably find something that will work for him.

  • Other GPS data tools (Score:2, Informative)

    by kelk1 (660671)
    Nice to release these libs. UNAVCO has a nice free tool called teqc [unavco.org], but does not release the source. Also found that link with many interesting things with source code: http://www.ngs.noaa.gov/gps-toolbox/exist.htm Admitedly, all this is not very useful for geocaching ;)
  • by alphakappa (687189) on Tuesday August 17, 2004 @07:13PM (#9996668) Homepage
    If you want to use your gps trakpoints and display them over satellite maps, the best source for maps (in the US) is Microsoft Terraserver which hosts USGS maps. Extracting the maps is another thing. However, there are some really cool tools to do that:

    1. USAPhotoMaps [jdmcox.com]. [FREE]This is a very simple interface which can download topology maps (the usual atlas maps), as well as black-and-white satellite imagery (down to 1 m), and color aerial maps (down to 0.25m for select cities.). It can also plot your gps trackpoints on the aerial photos/maps provided the output is in the form of garmin .gpx files, or some other formats. (Thankfully it is very easy to write a tiny program to convert your lat-long to these ASCII formats).
    Cons: cannot plot more than one trackpoint on the map.

    2. Quakemap [earthquakemap.com]. [Free initially, $9.99 to register]All the above features, plus the ability to plot as many trackpoints as you want plus a much more advanced interface plus the ability to track your gps receiver in real time over a satellite map (provided your receiver gives its output as NMEA). For 10 bucks, you get the ability to store the image files offline so that you can take this on a trip and see your vehicle tracked on cool aerial photos.

    There are other tools that can download terraserver maps, but none that has the ease of the above two. (Please correct me if I'm wrong.)

    There is an equivalent tool that does the same on OSX, but I can't recall the name.

    Is there any tool that can download aerial photos for free for the rest of the world?

10.0 times 0.1 is hardly ever 1.0.

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