            WXtrack - Satellite and ground picture prediction

Purpose:

This program is designed to predict the tracks of weather satellites both as 
paths above the earth, and as images produced by these satellites when 
scanning the ground.  It was designed for use during the early stages of my 
satellite receiving activities, when clouds and interference prevented easy 
identification of what I was actually observing!

It can read processed satellite images from one or more folders of your 
choice, and present these images side-by-side with the ground track 
prediction.  To make visual correlation easier, minute markers are produced 
on the predicted image to match those on NOAA APT transmissions.  Map 
overlay images suitable for subsequent combining with actual satellite 
pictures can be produced.


Known Limitations:

 o  The program displays most dates and times in UTC.  The local time is 
    provided as a "hint" on the time setting box for the World Map tab, and
    the program will search for files named with local time, as well as UTC.

 o  I do not have full scanner parameters for the RESURS and METEOR 
    satellites, so ground tracks are based on my best estimates comparing 
    with actual received pictures.  It seems that RESURS may not scan quite 
    symmetrically with a south-bound image being centred a little further 
    west than the predicted ground path.  Meteor 3-5 scans are considerably 
    non-linear.

 o  It seems that certain versions of Windows 98 may have a problem with the 
    "adjust for daylight saving time" being permanently set on.  If this 
    happens to you go to the Windows site at Microsoft and down load the 
    "Kernel Toys" for Windows 95 (is there one for 98?).  Try the Time Zone 
    Editor from the Kernel Toys suite.

 o  If the World map display is corrupt, simply switch to a different map 
    projection and back.


Installation, Files & Running:

Extract all files from the Zip file to a location of you choice, and run
WXtrack.exe.  See "Usage notes" later in this file for what to do next!  
If you get messages about missing DLLs, or even the misleading "A device 
attached to the system is not functioning" please read the section that
follows on Library Files.

The files included in the archive are:

  WXtrack.exe		the main program
  WXtrack.hlp		the help file
  WXtrack.cnt		the help contents
  WXtrack.txt		this file!
  UserMap.jpg		1800 x 900 pixel world map, hill shading, blue background
  amateur.txt		sample 2-line orbit information files
  stations.txt				"
  weather.txt				"
  horizon.dat		sample local horizon profile (for radio horizon)

If you wish accurate radio horizon display, you must edit horizon.dat to 
give the elevation angle of your local horizon for each azimuth angle.  If
you have no horizon data, please simply delete the file.  The program will
work perfectly well without it.

Optional downloads:
  LargeUserMap.jpg	1800 x 900 pixel world map, more details
  UserMap.jpg		1800 x 900 pixel world map, more details, hill shading
  countries.dat         country and state boundary data
  Overlay.bmp           master overlay bitmap
  MakeOverlay		Program to generate master overlay bitmap
  etopo5.elev           5 minute elevation data (not on this site)
  wave sounds for AOS   http://www3.sympatico.ca/konecny/golden/sounds.zip
        "               http://www.accesscomm.ca/users/monitoringpost/tips.htm

The more detailed world image maps are separate, as they don't change for 
new versions of the software so it seems unfair to ask you to download them 
every time.  Justin Priami KG4CEO has kindly provided a high quality bitmap
with the artic region shaded and more accurate country colours.  One user has
reported a problem when using the large map backgrounds, where the footprint
style become corrupted for one satellite.

If you wish a Spanish language help file, please see Ferran Alegret's Web 
site at: www.qsl.net/ea3dlv.  I am very grateful to Ferran for making this 
available as his time permits.

You should update the element files regularly, perhaps once a fortnight, 
from the Web site: www.celestrak.com/NORAD/elements/.  WXtrack will warn you 
when the orbit data is too old and needs an update, and you can update 
on-line with the Options, Update Keplers menu item.  Dr T S Kelso has 
articles at www.celestrak.com/columns/V04n03/ describing the format of the 
data in detail.


You may need four other library files:

1 - If you don't already have Borland's run-time library, you will also need 
to download the file VCL50.zip from any site offering it.  For example:
  www.satsignal.net  --> Software, Runtime Libraries

Extract the file VCL50.BPL and copy it to your Windows System folder (e.g. 
\Windows\System or \WinNT\System32).  Do not overwrite newer versions with 
old.

2 - If you don't already have the Intel JPEG library, you will also need to 
download the file IJL15.zip from any site offering it.  For example:
  www.satsignal.net  --> Software, Runtime Libraries

Extract the file IJL15.dll and copy to your Windows System folder (e.g. 
\Windows\System or \WinNT\System32).  Do not overwrite newer versions.

3 - If you don't already have the PNG LPNG-PX.dll library, you will also 
need to download the file lpng-px.zip from any site offering it.  For 
example:
  www.satsignal.net  --> Software, Runtime Libraries

Extract the file LPNG-PX.dll and copy to your Windows System folder (e.g. 
\Windows\System or \WinNT\System32).  Do not overwrite newer versions.

4 - If you do not have a recent Microsoft product installed, such as 
Internet Explorer, it is possible that you may get an error message saying 
that "This control requires version 4.70 or greater of COMCTL32.DLL".  In 
this case, you will need Microsoft's Common Control Library update from: 
  www.microsoft.com/msdownload/ieplatform/ie/comctrl.asp  (400KB)

There is information on analysing "Missing DLL" messages at:
  www.satsignal.net  --> Software, Runtime Libraries


Optional files:

If you wish to generate map overlays, you will need the file Overlay.bmp
which is available on the Web at this address:
  www.satsignal.net  --> Satellite Tools, WXtrack, Downloads
    Pre-compiled overlay bitmap  (404KB)

Extract the file Overlay.bmp to the same folder as WXtrack.exe.  The file 
will occupy 30MB when uncompressed, but fortunately compresses well!

If you wish to use cartographic data, as an enhancement to the Azimuthal
Equdistant projection, for example, you will need the file Countries.dat
which is available on the Web at this address:
  www.satsignal.net  --> Satellite Tools, WXtrack, Downloads
    Country & State boundary data  (459KB)

Extract the file Countries.dat to the same folder as WXtrack.exe.

If you wish, you can generate your own version of Overlay.bmp by using the
small MakeOverlay program listed on the Web page at:  
  www.satsignal.net  --> Mapping Tools
    MakeOverlay program V1.1.0  (31KB)

MakeOverlay requires the file Countries.dat mentioned above.  Note that 
running MakeOverlay requires at least 32MB RAM to generate at a reasonable 
speed, although it will work in 24MB but take many minutes.  You can change 
the gridline spacing, put the gridlines behind or in front of the land 
areas, and choose to add annotation in your font and size to the gridlines.

From version 2.7.4, WXtrack can make use of sound files to annouce a number of
events during the pass of a selected satellite.  Please note that these events
will be tracked ONLY if WXtrack is not minimised!  You can set up what events
to annouce by using the Control Panel (Start menu, Settings, Control Panel) 
Sounds option.  Under the Sound Events tab, scroll down the list of programs 
until you see WXtrack.  You will see the list of events that can make a sound,
and you can choose whatever wave file you want for each of the 8 sounds.  
There is also the option to turn off sounds within WXtrack itself, should you
wish to temporarily disable sounds.


Usage notes:

The program has four tabs, Setup, World Map, Ground Path and Flight.  It 
normally starts on the World Map tab, but you will be shown the setup screen 
when you first run the program.  Drag and drop the satellites you want from 
the Available to the Active list box.  You can test the program by switching 
to the World Map tab, but you will want to return to the Setup tab to enter 
the co-ordinates of your location.  Longitude is negative west of Greenwich,
and latitude negative below the equator.  More accurate predictions can be
made if you enter your height, and the average elevation of the radio 
horizon from your location.  You can add mutiple locations to WXtrack, and
a small set is supplied.  You can also have multiple horizon profiles, each
named according to your location.  If have no specific data, the file 
Horizon.dat is used.  If your location was named Edinburgh, then WXtrack
would first try the file EdinburghHorizon.dat.

You can choose the satellites that interest you by dragging and dropping 
from the available satellites list.  This list is built up from all two-line
elements files in the same folder as WXtrack.exe, or in a folder of your 
choice.  It is up to you to keep these files up to date.  You have three
lists or "banks" that you can fill with satellites.  This may be helpful if
you want to switch between Weather Satellites and Amamteur Radio, for 
example.  The pass generator will show you a list of passes for a single 
day, and when you select one of these passes the buttons which link to the 
World Map and Ground Path tabs become enabled.  If no files with satellite 
details are found, the list of available satellites will be blank.  You can 
name the files anything you want - the program will read all files ending in 
.TXT, .2LI or .TLE.  Duplicate entries for satellites in multiple files are 
allowed, and the program will then use entries with the most recent epoch.

You should update the element files regularly, perhaps once a fortnight, 
from the Web site:  www.celestrak.com/NORAD/elements/  and get the files:
resource.txt, stations.txt and weather.txt or whatever you desire.

You can print a diary of passes for the next few days, an ephemeris, either 
from the Setup tab, or from the main File, Print pass list menu.

The World Map tab allows real-time and manual updates of the chosen 
satellite positions, or you can open a file from WXSAT (e.g. 12250000.bmp 
for December 25th) to make the program use the date and time from the file 
as the map time.  The "selected" satellite will have dotted line showing its 
scan pattern on the ground.  The track of the satellite is shown by a number 
of dots marking the position in the previous few minutes.

The Ground Path tab allows two functions, the prediction of a ground path 
given the satellite, start of pass, and direction of pass, and loading an 
actual satellite image.  You can choose the folder (or folders) containing 
these images from the setup tab.  The filename is assumed to be in WXSat 
format, but to allow the viewing or processed visible or IR images, various 
file extensions are recognised:

Visible: -2.jpg, V.jpg, V.png, V.bmp, -C.jpg, C.jpg, C.png, C.bmp, B.bmp,
         -4.jpg, I.jpg, I.png, I.bmp, .jpg, .png, .bmp

IR:      -4.jpg, I.jpg, I.png, I.bmp, -C.jpg, C.jpg, C.png, C.bmp, B.bmp,
         -2.jpg, V.jpg, V.png, V.bmp, .jpg, .png, .bmp

So if today is March 26, and the time 12:58 UTC, then the filename from 
WXSat might be 03261258.bmp, and you may have processed the pass to produce 
a false colour file that you have called 03261258-C.jpg.  This file would be 
the first one found as shown in the table above.  The program also tries to 
look for files a few minutes on either side on the nominal, and also files
named in your equivalent local time.

I have specifically included PNG file support as this format is typically 
only about 2/3 of the size of a BMP file, but without any loss of quality 
that is associated with JPEG files.  Storing images as JPEG files can cause 
errors in the level of the telemetry bars, required for apparent temperature 
measurement.

(Note that I am assuming that an image contains a single picture, not a 
combined side-by-side channel A and channel B picture.  I currently store 
side-by-side PNG images as my master image, and processed JPG images for 
each channel.)

You can zoom and scroll both the map and the picture.  Normally, scrolling 
the map will scroll the picture as well, but as there might be some 
misalignment, perhaps the satellite wasn't acquired at the start of the 
pass, scrolling the picture will, intentionally, not scroll the map.

As ground path prediction can take some time, pressing the escape key will 
interrupt.  Each time a new ground path map is generated, a copy will be 
saved as a file named Result.jpg in the same folder as the program.  Note 
that this file will be overwritten every time a new pass is created, so save 
it if you want to keep it!  Both the Result.jpg file and the other results 
files will accumulate in the WXtrack folder, unless you have used the "Path 
for Results Files" on the setup tab to redirect the output.

The Flight tab allows you to fly a pass, either what a satellite is doing in 
real-time, or an earlier pass.  Enjoy this strictly for fun mode!


World Map data:

The predicted picture quality on the Ground Path and Flight tabs can be 
substantially enhanced by downloading higher resolution topographic data 
than that supplied with the program in the *UserMap.jpg files.  The backdrop 
on the World Map tab will _not_ be affected, only the Ground Path and Flight 
tabs.  The highest resolution data in the *UserMap.jpg is at 12 minute angle 
intervals, and is compressed with JPG resulting in slight artefacts.  If the 
image quality is adequate for you, then you do not need the higher 
resolution data.  However, using the ETOPO5 5 minute data will increase the 
number of pixels in the predicted image by about 5.6 times - more when you 
consider that it is not compressed.

The program will use the US National Geophysical Data Center (NGDC) ETOPO5 5 
minute data file for ground path prediction if the file etopo5.elev is 
present in the same folder as the program executable.  This data file may be 
obtained from the Internet, for example:

  http://edcwww.cr.usgs.gov/Webglis/glisbin/guide.pl/glis/hyper/guide/etopo5
  18662400 bytes (unzipped)
or:
  www.geol.binghamton.edu/faculty/jones/etopo5.zip
  18666720 bytes (unzipped)

Be warned that this zip file is an 11MB download that expands to 18MB when 
unzipped.  But the results _are_ worth it.  NGDC can supply the data on 
CD-ROM (product code 1093-A27-001).  I am advised that the price is around 
$100 or online ordered $75, plus $11 shipping and handling, plus for outside 
the US a currency charge of $10.  The product number is G01093-cdr-A0001 and 
the e-mail address is pkd@ngdc.noaa.gov, the URL is:
www.ngdc.gov/mgg/fliers/93mgg01.html

Data from these two sources are not identical, the earlier Jones data has 
one extra 16-bit field per line, and has a different byte order.  WXtrack 
attempts to determine which file you are using, and to behave appropriately.  
Using the high-resolution data file will not alter the appearance of the 
world map display, simply the predicted ground path (and the Flight mode 
display).


Using Image files:

The images must be named according to the WXsat convention - MMDDhhmm.bmp or 
whatever.  For example, without a pass selected, the program starts up with 
the date 26th February 1999 at 1327 in the "When" box on the "Ground Path" 
tab.  It would therefore look for files named 02261327.jpg.  When using the 
"Timeframe from File" option on the World Map page, loading a file merely 
sets the date and time for the satellite display.


Notes:

The program is written for Borland's Delphi 5.01, but you do not need access 
to Delphi to run WXtrack.  The program has been developed on Windows NT 4.0 
and runs on Windows 2000, 95, 98, ME as well.


Release information:

2001 Feb 10  2.8.2  Correct Invalid Floating Point error ..
                    .. compute_passes_today being called before date correctly set  


See the Help, What's New menu for complete release notes.


Program Status & Distribution:

This program is freeware, and remains copyright of David J Taylor, 
Edinburgh, 2000.  This program is provided "as is", without any support from 
me.  At www.egroups.com/subscribe/SatSignal, here is a self-help mailing 
list where other users of the software may be contacted.  Whilst I cannot 
answer queries relating to the use of this program, I'd value any comments 
or suggestions for improvements you may have.  If you report a problem, be 
sure to include the full program version number (from the Help, About 
command), and the details of the operating system you are using.


Acknowledgements:

First, I would like to thank all the folk who have bothered to download and
try out this software, and the valuable suggestions you have all made are
built into the current version of the program.

Many routines were modified from Dr TS Kelso's invaluable SGP4 routines, 
used with permission, which are:
  Copyright (c)  1991-1999, Dr TS Kelso, All Rights Reserved
  E-mail:   tskelso@celestrak.com
  Web site: www.celestrak.com

Dr TS Kelso's site at: www.celestrak.com/NORAD/elements/ provided the
orbital elements, and is your source for up to the minute data.

Footprint calculation code adapted from James Miller's (G3RUH) 
"PLAN-13 SATELLITE POSITION CALCULATION PROGRAM" available at:
  ftp.amsat.org  /amsat/articles/g3ruh/a111.zip

The moon prediction code was adapted from Paul Schlyter's comprehensive 
orbit calculation page at:
  http://hotel04.ausys.se/pausch/comp/ppcomp.html

The PNG support is from Edmund H Hand's interface to LPng.dll
  e-mails:  edhand@worldnet.att.net
  updated by: Dominique Louis (Dominique@SavageSoftware.com.au)
              Uberto Barbini (uberto@usa.net)

The library LPng.dll is freeware and the source is:
  Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
  Copyright (c) 1996, 1997 Andreas Dilger
  Copyright (c) 1998 Glenn Randers-Pehrson

TVersionInfoResource is from Brad Stowers
  www.pobox.com/~bstowers/delphi/
  Copyright bstowers@pobox.com (CompuServe 72733,3374)

Thanks to Milan Konecny and Craig Orban for making sound files available on 
their sites.


Contacting the author:

Web site:  www.satsignal.net
E-mail:    davidtaylor@writeme.com
2001 Feb 10
