OziExplorer Tracklog File Format

I searched around the web high and low and could only find limited information on the OziExplorer tracklog file format that is stored in the .plt files. 

OziExplorer has PC and Windows Mobile versions making it a great tool for tracking/logging and planning your travels. Tracklogs save your tracks as you travel: saving on your portable mobile device saves space in your vehicle (or even in your pocket!) and allows you to copy the tracklog files to your PC for viewing on the big screen later.

On our recent trip around Australia, we saved all of our treks using OziExplorer.

My analysis has determined the following from two versions v2.1 and v2.0

.plt – Extracts:

v2.0 from OziExplorerCE
1.    OziExplorer Track Point File Version 2.0
2.    WGS 84
3.    Altitude is in Feet
4.    Reserved 3
5.    0,2,255,OziCE Track Log File,1
6.    0
7.    -26.7597652, 150.6400882,0, 1047.9,40165.0451620 ,181209,000505.3
8.    -26.7597353, 150.6400796,0, 1114.8,40165.0457292 ,181209,000554.3
9.    -26.7597090, 150.6400779,0, 1139.1,40165.0473380 ,181209,000813.3
10.  -26.7596040, 150.6400643,0, 1151.2,40165.0475810 ,181209,000834.3

v2.1 from OziExplorer PC
1.    OziExplorer Track Point File Version 2.1
2.    WGS 84
3.    Altitude is in Feet
4.    Reserved 3
5.    0,2,255,OziCE Track Log File ,1,0,2,8421376
6.    1257
7.    -26.759765, 150.640088,0, 1047.9,40165.0451620, 18-Dec-09, 1:05:01 am
8.    -26.759735, 150.640080,0, 1114.8,40165.0457292, 18-Dec-09, 1:05:51 am
9.    -26.759709, 150.640078,0, 1139.1,40165.0473380, 18-Dec-09, 1:08:10 am
10. -26.759604, 150.640064,0, 1151.2,40165.0475810, 18-Dec-09, 1:08:30 am

Description
Line 1 – Type and version information
Line 2 – Datum used
Line 3 – Just a reminder the altitude is always stored in feet
Line 4 – Reserved for future use
Line 5 – 0,2,255:RGB colour of track; OziCE Track Log File: track description; 1:trackskip value – usually set to 1
                for v2.1 – extra fields: 1,0,2,8421376
                   1 – trackskip value
                   0 – trackType: 0=normal; 10=closed polygon; 20=alarm zone
                   2 – track fillstyle: 0=solid; 1=clear; 2=back diagonal; 3=forward diagonal; 4=cross
                   8421376 – track fill color (RGB)
Line 6 – number of trackpoints in the file. Not updated in v2.0. Redundant as the number can be determined when reading the records

Track log records
Lines 7 to end: data records of track log

Field
1.    -26.7597652 latitude
2.    150.6400796 longitude
3.    0 0=normal; 1=break in track line
4.    1047.9 altitude in feet 1047.9 ft = 319.39992m
5.    40165.0451620     date/time 40165=days since 30/12/1899 i.e. 40165 = 18/12/2009 (18 Dec 2009)
                                                                    0451620 is fraction part of day in localtime zone, i.e. 0451620 = 01:05:02am. This appears to be in UTC time (not local time)
v2.0
6.    181209 date ddmmyy
7.    000505.3 time seems to be some rounding discrepancy between v2.0 & v2.1
v2.1
6.    18-Dec-09 date dd-mmm-yy
7.    1:05:01 am time UTC? time?

NOTE: Fields 6 & 7 are ignored by OziExplorer
              Field 7 appears to have a discrepancy in the calculation of the time from field 5 (the minutes are different)

The OziExplorer date/time format is the OLE date/time value stored in it’s raw double format. The .NET DateTime class provides a build in function to construct a DateTime from this value:

1
DateTime timestamp = DateTime.FromOADate(40165.0451620);

Edit (20/2/2010): I have since found this link:
http://www.rus-roads.ru/gps/help_ozi/fileformats.html

Enjoy!

[Edit 21/2/2010]
Corrected time conversion – I was a decimal place out.
Added a method to convert the OziExplorer date/time to a .NET DateTime.
The OziExplorer time format appears to be stored in UTC format.

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