F70G 720P Dual Lens DVR Dash Camera (with GPS option)

What is your problem with the MAP files?
Can you upload somewhere like sendspace.com some MAP files?

enjoy,
Mtz
 
blue_q has sent me a .map-file on my request - thank you for your help, blue_q!

The file is a proprietary binary format, nothing that I have ever seen. It seems to be even specific for DVRs, as it contains references to a .mov file.

As far as I understand, it does contain a time stamp, but I am not sure what it is. Probably terrestrial time, loosely related but not equal to UTC. But I can only suppose that for now. There seems to be, apart from the position, at least another three-digit tag, which could be speed or track (direction).

I have not yet managed to decode it. For decoding it, I will need further information and data. I don`t want to bother you both, so I placed another order again. Lets see if I`ll get my hands on a unit this time.

Above, there is a link to another camera, DashCamMan supposes it to have simlar hardware. Even in the sample video, the GPS longitude is slightly off: the video has probably been taken in Canada, the GPS position overlay shows a position the italian alps...
I don`t know where the video has been taken exactly, but a latitude error of +90 degrees comes to mind when used on the western hemisphere (negative latitude).

The overlay shows position, speed, and another value (012) that I cannot interpret. It doesn`t seem to be track/direction, as it remains fixed even if the car turns 90 degrees. It could be the number of satellites acquired, but i that doubt acquiring 12 satellites in the same geographic position would be possible.

It would be very helpful having a video or at least a screenshot at hand that shows the video with GPS overlay data (position, speed, whatever), the corresponding .map file and maybe a NMEA track log or similar of another GPS receiver. --> Could someone please post a screenshot?

For my own use, having a speed tag on the screen will be sufficient, but obviously I will try to decode the format, as I want my data to be accessible without special software.

There is another possible drawback: if the GPS position overlay is way off, and the speed tag updating only with a delay of more than very few seconds (one to two seconds is normal), then the police or a judge may eventually discard the whole video as inappropriate for evidence.

In this case, the only useful application of GPS in this unit would be having the clock synchronised automatically - if it works.

Maybe -without having investigated the details yet- it is advisable to choose another logger or logging DVR if GPS data is really important.
 
OK, if you don't want to public post that MAP file you can send it to me using private message.

enjoy,
Mtz
 
dashcamjunior said:
It would be very helpful having a video or at least a screenshot at hand that shows the video with GPS overlay data (position, speed, whatever), the corresponding .map file and maybe a NMEA track log or similar of another GPS receiver. --> Could someone please post a screenshot?

not sure how helpful a screenshot would be, here is a one minute video from my cam with the corresponding NMEA file you can download, maybe it is more useful to have a look at the data http://www.mediafire.com/?czc96j7tqkgangt

the included Registrator Viewer has options to export the GPS data in different formats, maybe that's useful also in helping to decipher things
 
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I just finally tried the GPS yesterday and found it was about 20 miles east and twisted about 90 degrees clockwise. I just sent a message to the seller to see if they can look into it. As far as I can tell, the route, relative to the road, is correct. It appears to be an issue with the software in reading or displaying the correct location on Google Maps.
 
This is good if is only about PC software and not the firmware or camera. So your files are correct and you just need a future PC software which will read your MAP files.
You just need to wait some time and the problem will be solved by some new version of a program.

enjoy,
Mtz
 
Well, we would have to prove if GPS data or it`s interpretation by the reader program is incorrect.

Thank you for posting your files, jokiin (btw: nice, clean city). To decifer the .map file, both files, NMEA and the corresponding map-file would be helpful. However, as you have another camera, it is not sure that the file format is the same as the F70G`s.

However, my unit is on it`s way and should arrive in some days. It seems to have passed customs inspection. I am really curious. Today I cleaned my car and noticed that it will not be easy routing the cable for the rear camera, nor placing the GPS receiver. :?

Regards,

Hans
 
Man, you don't nee to "decifer" anything. Save your time and just wait for a new version of some viewer program which will show to you the correct GPS data.
The MAP files created by F70 are correct, even if the tested ones by me don't have any G information, but just the GPS data.

But if you like to decifer, there is no problem, I agree with people which like to learn and discover.

enjoy,
Mtz
 
Mtz, I don`t want to learn for fun, but I refuse to use Windows. So I'll probably have to try to decode the gps log by myself and convert it to some commonly used format. I don`t know yet if I will be able to do so, but running Linux sometimes leads to "learn and discover", as you call it. ;)
I definitely won`t be able to write any viewer software, as I don`t have have any knowledge of graphic interfaces and multimedia files.

As I understand your posting, you have approved that the original map files do contain correct position data? Good to know that it is no hard- or firmware problem. How did you test the files?

Regards,
Hans
 
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dashcamjunior said:
How did you test the files?
In a future release of a viewer, not public.

enjoy,
Mtz
 
I'll add an observation I noticed with the included software:
The route is correct. It shows me driving essentially in a circle to leave the parking lot and then get on the highway. The route/trail is correct. The issue is that it's about 10 miles off and is aimed in the wrong direction. My sample file should show me traveling southeast, but the software renders it as southwest.

I have a feeling their software was designed for the China quadrant of the earth and they have an integer definition in the code somewhere that should allow a negative variable, but it doesn't. I think it's something simple like that. Just a tweak to the GPS decoding algorithm should fix it.
 
blue_q said:
I have a feeling their software was designed for the China quadrant of the earth and they have an integer definition in the code somewhere that should allow a negative variable, but it doesn't. I think it's something simple like that. Just a tweak to the GPS decoding algorithm should fix it.

GPS mapping data for China is manipulated by the government, the GPS results in China are out by less than 1km though, generally around 500 to 800 meters off except around military areas where it is further off, this only shows up as a problem in Google maps in the regular map mode, if you view in satellite mode the route is actually shown correctly

I'm not sure this has anything to do with your problem if you're out by 10 miles
 
I had a similar thought when viewing the video of the (maybe?) similar dashcam cited above. Driving in Canada, GPS shows Italy. Longitude is plausible, latitude shown is +7°, while most cities in Canada at this longitude seem to be at around -63 to -73°. A +80° (or +90°, if footage comes from the US) offset comes to mind, and could be indeed a problem of handling negative values.

However this seems unrelated to a 10 miles offset. Should be no problem anymore, as Mtk stated that the errors are related to the viewer software (in the case above, it doesn`t seem so, as the coordinates are taken from video footage, not the viewer software).
 
DCJ, please read again here.

Here is a screenshot from the F70G file which contain its GPS .map data. I think the position on the google maps is correct.

All you need to do is just wait until next week for the new release of the viewer.
OK?

enjoy,
Mtz
 

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No problem, junior, MTK is also a great name. I wish I am MTK (MediaTek) and millionaire. :lol:

enjoy,
Mtz
 
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Oh, no, Vadikus, why posting here? :lol:
The next F70 users question is when will be supported also the rear camera PIP view over the front view.

Will be nice if you will open a thread about Registrator Viewer.

enjoy,
Mtz
 
Mtz said:
Will be nice if you will open a thread about Registrator Viewer
I'm not sure, that I will be able to support thread.
Really, only today I answering to the questions and sending old problems to new released version.
 
Not necessary to support it. But maybe when you have time to read some idea from it or to announce some new version.

enjoy,
Mtz
 
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