Category: Dash Cameras

Extracting GPS data from Viofo A119 and other Novatek powered cameras

The script.
nvtk_mp42gpx.py
Here it is: nvtk_mp42gpx.py
Alternative version: nvtk_mp42gpx_older.py

What does it do?

This script will attempt to extract GPS data from Novatek MP4 file and output it in GPX format.

Usage: ./nvtk_mp42gpx.py -i<inputfile> -o<outfile> [-f]
        -i input file (will quit if does not exist)
        -o output file (will quit if exists unless overriden)
        -f force (optional, will overwrite output file)

In short: it takes Novatek encoded MP4 file (with embedded GPS data) and extract GPS data in GPX format (as separate file). Note; it does not modify the original MP4 file.

In long:
Continue reading Extracting GPS data from Viofo A119 and other Novatek powered cameras

mini0806 design flaw

Alternative title: why my mini0806 was crashing and stopped working after a light drop.

One of the differences between mini0805 and mini0806 is this heat sink:
IMG_20160703_110658

It is a bitch to remove, so I gently coerced it with a blade:
IMG_20160703_110803

After some time of gentle pushing and heating it managed to peel off:
IMG_20160703_111536

Revealing Samsung ram chip and Ambarella A7LA50 SoC:
IMG_20160703_111758

Here is why it was not working after slight drop (and crashing before that):
IMG_20160703_113213

Pulled out pads! Note that the blade I used to remove would cause other side of pads missing if I applied too much pressure.

My theory is following: the heat sink that bridges RAM and SoC is causing stress on these chips. Mostly because it is glued and not mechanically pressed against the chips. This is a very silly design flaw, if for example, only SoC would have the heat sink (like found on IP cameras) then there would not be any stresses. I don’t think RAM needs heat sinking on those things.

I am tempted to take dremel to my other mini and split the heat sink in two…

inside of Mini0806

Update: if you ever thinking about buying this camera, don’t! Unless you wish to buy five them to get one good. It is plagued with issues, from assembly problems (jammed cable), crappy firmware, stability issues, poor choice of power supply IC (only 0.5V head room), random crashes to shitty plastic case that melts at 100’C.

Below is the breakdown of mini0806 dashcam.

The packaging contents:
IMG_20150727_161216

Camera itself:
IMG_20150807_113915

IMG_20150807_113946

IMG_20150807_113937

To open pop the rear cap with fingers:
IMG_20150807_132100

There are screws behind it holding the whole camera together:
IMG_20150807_132254

Notice torn cable inside of the ring? This is a common assembly/design fault:
IMG_20150807_132408

The shell is easily separated:
IMG_20150807_132554
The beefy heat sink is a good thing to have, I believe it is relatively easy to add a micro fan there (maybe with minimal case cutting).

IMG_20150807_132613

The two boards held together quite tight. Here is the camera side:
IMG_20150807_133206

IMG_20150807_133216

Here is the back side:
IMG_20150807_133319

Notice how battery is simply jammed between two halves? It is held by double sided tape…

Under the battery:
IMG_20150807_133359

I have added insulation tape around battery area in case the battery swells in future:
IMG_20150807_133725

Camera is easily assembled back, one thing to watch out for is the power/GPS cable that feeds through the ring. It can be easily jammed and torn by adjusting the angle, if it is not assembled carefully. I bolted the contact pad last which allowed me to check if the cable is jammed.

Navman (Mio) MiVue 388

Navman_MiVue388

I bought Navman MiVue 388 for holiday in Australia, as I was going to do a few thousands kilometres worth of driving.
This camera is sold everywhere else under Mio brand. It is not a Navman product.
When I was purchasing this dash camera I had few prerequisites (which it met, somewhat):
1) 1080p
2) suction cup mount (for easy removal from rental)
3) Modest size
4) Available next day
5) Reasonably priced (under $250)
6) GPS
So basically the only product in New Zealand that met those was this camera.

Whatever you do, do not buy this dash camera. There is nothing really positive I can write about it (apart that it supports 64GB VFAT formatted card, despite the specifications). It pales in comparison to a much cheaper G1W, or Mini0806 (also crap! DO NOT BUY THESE!) or even my dated Blackvue DR400G-HD II. If you are after a good value for money camera get G1W for ~$60USD. Same applies to MiVue 338/358.

Image quality is very grainy:

I didn’t test the camera with optional CPL filter as Navman didn’t sell it at the time (it could have been sources from eBay as Mio branded).

Beyond image quality there are other major issues:

* Suction cup mount is a standard GPS mount, is way too big and vibration prone. It is not very good and falls off after few hours. Not possible for discreet mounting in a smaller car without major view obstruction.
* After 1 month of operation the face plate (screen cover) fell off. It was stuck on by two short strips of double sided tape. After reattaching second time, I gave up and now the camera is used without it.
* Occasionally it decided to completely lose time settings and gets stuck on Setup Time screen. While in that state it does not record!!!
* Cannot turn off blue pixelated “MiVue388” logo on top of the screen (without hacking firmware).
* Battery life is hopeless (about 1 minute and 30 seconds). Good luck actually using park mode.

Two of the issues were because of the climate in New Zealand; this camera is not suitable for being attached permanently on the windscreen due to heat. It is probably far worse for it in Australia.

To address the shitty mount I have decided to build my own mount (secured by not suction cup but double sided tape).
The materials I used are the following:

* Piece of scrap aluminium plate (some random cut off)
* A random drawer knob that I found at hardware store (a 16mm ball with threaded hole and a screw).
* 3M moulding tape
* Black paint

IMG_20140816_125834
IMG_20140816_125848
IMG_20140816_125901
IMG_20140816_125928

Test fit:
IMG_20140816_130112
IMG_20140816_130157

Painted and assembled:
IMG_20140816_131827
IMG_20140816_131849
IMG_20140816_132327

Finished product:
IMG_20140817_141948
IMG_20140817_142026

With my mount the dash cam no longer blocks the view, in fact it is almost not visible (apart from status LED) from drivers seat. It is also very discreet from outside as it is masked by mirror contour.

Converting Blackvue Dashcam gps log

It appears that Blackvue dashcams log GPS data in “almost” NMEA format.
It is possible to convert the file using gpsbabel utility into KML format that google maps/earth can understand.
All you need to do is strip time stamp appended to each line in the log and them process the output with gpsbabel:

cat {BLACKVUE_GPS_LOG}.gps | awk -F ']' '{ print $2 }' | egrep -v '^$' > {BLACKVUE_GPS_LOG}.nmea
gpsbabel -i NMEA -f  {BLACKVUE_GPS_LOG}.nmea -o KML -F {BLACKVUE_GPS_LOG}.kml

This is what log looks like:

[1389266060242]$GPRMC,221417.990,A,4533.1826,S,16737.5506,E,054.7,035.5,080114,,,A*77

[1389266060242]$GPVTG,035.5,T,,M,054.7,N,101.4,K,A*0C

[1389266060242]$GPGGA,221418.990,4533.1701,S,16737.5631,E,1,11,1.1,204.6,M,1.7,M,,0000*78

[1389266060242]$GPGSA,A,3,16,07,03,19,23,13,10,06,09,27,08,,2.0,1.1,1.7*3D

[1389266060242]$GPGSV,3,1,12,13,80,310,39,07,50,247,36,23,50,019,48,03,48,066,46*71

[1389266060242]$GPGSV,3,2,12,16,45,128,43,27,42,084,44,06,41,096,44,19,28,038,46*79

[1389266060242]$GPGSV,3,3,12,10,26,260,31,08,19,261,32,09,16,257,26,05,06,210,*77

[1389266061239]$GPRMC,221418.990,A,4533.1701,S,16737.5631,E,054.8,035.0,080114,,,A*7F