Format of GPS data?

[DAP]

I'm using linux, and there are no dashcam viewers for linux.
VLC works fine for viewing the video, slight hickup between files, but that is not a problem.
I tried using GPSPrune for viewing the GPS files, but it does not recognise the file format.
The standard format for GPS data is GPX, but the camera uses a text based LOG file.
GPSPrune can import a text file, but you must tell it what fields are what (it does a bad job of guessing).

Has anyone figured out what the colums are in the LOG file format?

I just tried GPSBabel, this format is not listed.
I've figured out a few things:
example line:
A,110914,015859.000,3722.9935,N,12148.9924,W,034.9,+00.61,-08.58,+00.61;
"V" before GPS acquires lock, "A" afterwards, date (ddmmyy), time (hhmmss.ms), latitude (dddmm.mmmm), polarity of latitude,longitude (dddmm.mmm), polarity of longitude, speed (not MPH, not M/sec, not KPH), acceleration in M/sec^2 left, Acceleration in M/sec down (reads -9.8 when stopped), Acceleration backwards (positive when brakeing)

 

[anitka]

Two days I have been solving the same and I have succeeded! But you was the first so I couldn't help you. ;-) Now you have complete information to write your own script to handle theese datas. I'm about to do so.. Bye

 

[Nigel]

speed (not MPH, not M/sec, not KPH)

Speed is in knots (as used by ships)

 

[anitka]

Thank you. I hope it will be helpful to someone else as I was curious about coordinates and time only. ;-)

 

[DAP]

Knots? that is used by ships & aircraft. This is a device used in cars!
I really wish people would follow standards that already exist. If you look at GPSbabel, it supports more than 100 different GPS files formats. We only need one! None of the variants offer any advantage over GPX, and it is open, and more important, free.

 

[jokiin]

Knots is the standard, that is all that is transmitted

 

[anitka]

If anybody needs online convertor supporting mentioned data format (e.g. TrueCam) there is one here: http://www.gpsvisualizer.com/convert_input

 

[DAP]

If anybody needs online convertor supporting mentioned data format (e.g. TrueCam) there is one here: http://www.gpsvisualizer.com/convert_input

Thank you, but I would prefer not giving this web site information about where and how fast I drive.

I tried all of the formats currently supported by GPSbabel, and unfortunately, none work with the log files from this camera.
I created a XCSV format file for GPSbabel that contains the following:
DESCRIPTION MINI-0803 Dashboard camera AKA E-PRANCE A7
EXTENSION log

FIELD_DELIMITER COMMA
RECORD_DELIMITER NEWLINE
DATATYPE TRACK

IFIELD IGNORE, "", "%14.14s" #Indicates satilites acquired ("A"==acquired, "V"==not acquired)
IFIELD LOCAL_TIME, "", "%d%m%y"
IFIELD HMSL_TIME, "", "%02d%02d%06.3f"
IFIELD LAT_DDMMDIR, "%f", "%09.4f"
IFIELD LAT_DIR, "", "%s"
IFIELD LON_DDMMDIR, "%f", "%010.4f"
IFIELD LON_DIR, "", "%s"
IFIELD PATH_SPEED_KNOTS, "", "%05.1f" #knots
IFIELD IGNORE, "", "%14.14s" #meters per second Acceleration to the left
IFIELD IGNORE, "", "%14.14s" #meters per second Acceleration downwards
IFIELD IGNORE, "", "%14.14s" #meters per second Acceleration backwards

This sort of works, but it puts my track in China instead of California, and does not keep the acceleration data. For some reason, the IFIELD LON_DIR line is not working.

 

[jokiin]

This sort of works, but it puts my track in China instead of California, and does not keep the acceleration data. For some reason, the IFIELD LON_DIR line is not working.

sounds like you have a parameter wrong there somewhere, if you have opened up the GPS mount and have the model number I might have a datasheet for it, the data sheet gives all the details of each field which might help point you in the right direction

 

[DAP]

sounds like you have a parameter wrong there somewhere, if you have opened up the GPS mount and have the model number I might have a datasheet for it, the data sheet gives all the details of each field which might help point you in the right direction

I think I have the format of the log file worked out correctly (see the 1st post in this thread). The problem is that I don't really understand the xcsv file format that GPSbabel uses very well.

No, I have not opend up the mount for the camera, that is currently thouroughly glued to my windshield of my car, so opening it would be problematic.

 

[jokiin]

your location being in China suggests something is wrong, it reads correctly in programs like Registrator Viewer so it's safe to say the data itself is ok, just the interpretation is incorrect

this is from one of our models so won't match what you have but this is basically how they are represented

$GPRMC, 161229.487, A, 3723.2475, N, 12158.3416, W, 0.13,309.62, 120598,, *10

the fields are as follows



If anyone knows the model number of the GPS you might be able to get the datasheet that will have the same type of info for your model, might be of some help, probably only something minor there that is still wrong

 

[DAP]

What is wrong is that the sign of the longitude should be negative since the letter "W" is included in the string. In the converted file, the longitude is positive, so instead of being measured to the west, the longitude is being measured to the east, putting me in China. All of the other data is being handled correctly.
This is entirely a problem with the "IFIELD LON_DIR" line of the GPSbabel translation file not working the way I think it is supposed to work.

 

[jokiin]

yeah I don't know anything about the service you're trying to use unfortunately, I'd really like to see a Linux version (something for Android would be nice also) of one of the viewers one day though, I've used Linux for many years but one of the things that leaves you stuck to using other operating systems is the lack of specialised software like this

 

[DAP]

What would really help is if vendors would stop inventing new GPS file formats and use GPX directly (http://www.topografix.com/gpx.asp). This is a trivial thing for them to do (change the format of the print() command). GPX is supported by nearly every tool that views GPS data, including google earth.
GPSbabel is not a service, it is a GPL licenced (free with source code) program available for most OSs: http://www.gpsbabel.org/ It is a tool specifically for translating one GPS format to another. It supports more than 100 different GPS file formats, but does not yet support this one.

 

[jokiin]

No vendor is going to the trouble of inventing new formats, they use the industry standard formats that are already there, NMEA-0183 is most common, there are a couple of proprietary formats as well but rarely seen in this product category

The output messages can be in a few different formats, RMC is maybe one of the more common ones, that can vary depending on where the product is to be used though as different systems are used in some countries

GGA Global positioning system fixed data
GLL Geographic position—latitude/longitude
GSA GNSS DOP and active satellites
GSV GNSS satellites in view
RMC Recommended minimum specific GNSS data
VTG Course over ground and ground speed

Would perhaps be better if whoever writes these 3rd party software programs looked at what is out there and updated their programs to suit, assuming there's some market need for this from car cameras, not sure that's the case though so perhaps little incentive

 

[DAP]

If this were an industry standard, GPSbabel would already support it.

This file format includes accelerometer data, are you saying that the GPS module used by this manufacturer contains a built in accelerometer?
I think the GPS base includes a GPS module, and a separate accelerometer IC. I believe the camera is monitoring both, combining the data and saving it to its own newly invented file format.
If manufacturers were using industry standard formats, GPSbabel would not need to support 100 different file formats. There is no need for 100 different file formats.

 

[Schorschi]

I've looked at a couple of log files from my 0803 and noticed that the acceleration values never change within the same log file. They will be different between log files. My "down" value is at -09.19 though for all files. Do I have a faulty GPS module? Or perhaps I have to activate a feature?

Also, I noticed when using the QtPlayer.exe application that is on the internal medium, not all (video) files stored in a folder will show in the player, possibly because the associated GPS log file is deemed unreadable. For one video file that is not showing in the player, I have 199 out of 239 lines beginning with a "V" (i.e. no GPS lock). For another, that does show up in the player, only the first four lines are starting with "V" out of a total of 216 lines.

 

[DAP]

I've looked at a couple of log files from my 0803 and noticed that the acceleration values never change within the same log file. They will be different between log files. My "down" value is at -09.19 though for all files. Do I have a faulty GPS module? Or perhaps I have to activate a feature?

It is likely that your accelerometer is faulty.
I was able to figure out what the accelerometer numbers were by correlating the numbers with what was going on in the video at the same time, and remembering that 9.8 m/s^2 was the acceleration of gravity.

Actually it occurs to me that the accelerometer must be in the camera, and not the base since only the camera is going to be level (aimed forward). Every windscreen is at a different angle. Vertical for trucks & busses to nearly horizontal in a sports car.

 

[Nigel]

I've looked at a couple of log files from my 0803 and noticed that the acceleration values never change within the same log file. They will be different between log files. My "down" value is at -09.19 though for all files. Do I have a faulty GPS module? Or perhaps I have to activate a feature?

I've noticed that too on my 0803, but the values look OK in Registrator Viewer. Don't think it is configuration, they work fine in the 0806 set up in the same way

 

[jokiin]

This camera has an embedded data file with the video, not just the flat text file you're looking at, perhaps Registrator Viewer is referencing that data

G-Sensor is built into the camera, not the GPS

If this were an industry standard, GPSbabel would already support it.
.

Maybe GPSbabel needs to look at what's happening in the market, majority of car cameras use these same formats, seems that program has been all about other devices so perhaps not something they've looked at as yet, not even sure their program is useful for anything to do with car cameras though so there might not be any reason for them to look, don't know their program and what other uses it might have

If you're trying to make a player I'm not sure this is the most efficient way to go about it, maybe something else you have in mind though