wangaiguo / gopro2gpx

Parse the gpmd stream for GOPRO moov track (MP4) and extract the GPS info into a GPX (and kml) file.

About gopro2gpx

Python script that parses the gpmd stream for GOPRO moov track (MP4) and extract the GPS info into a GPX (and kml) file.

Tested on a GoPro7, but it should work on any camera above the GoPro5.

Tested on Windows7 and MacOS Sierra.

I always like to print some additional info overlaying my action videos. These overlays will show data about speed, elevation, gps info, and so on. I started a project wrotten on python 2.7 that works fine. gets a gpx track file, a mp4 file and some configuration, and builds an overlay with the data:

• Python Overlay 1.0
• Python Overlay 2.0

Recently, I bought a Gopro7 black, that supports GPS inside the camera. Gopro's Quik allows you to process the metadata stored along the videos, and show it as an overlay. I want to extract the data from the MP4 file, so I start to read about in the web. The data is stored in a format called *GPMF, you can get all the info in this repo https://github.com/gopro/gpmf-parser. Also, there are some implementations in go. Check this repo https://github.com/stilldavid/gopro-utils/.

My idea is process the file in python, extract the data, and build a file in a known format. I generate kml and gpx.

Dependencies

• Python3
• FFmpeg and FFprobe binaries
• Valid MP4 with GPS data inside. Record something with your cam.

Installation

1. Clone the repo gopro2gpx in your machine, extract it.
2. Ensure you have python3, FFmpeg and FFprobe installed in your system.
3. Edit config.py and modify the following lines to point to your binaries:

     if platform.system().lower() == 'windows':
        config = Config('C:\\Software\\ffmpeg\\bin\\ffmpeg.exe', 'C:\\Software\\ffmpeg\\bin\\ffprobe.exe')
    else:
        config = Config('/usr/local/bin/ffmpeg', '/usr/local/bin/ffprobe')

4. Run it (skip bad points, show the labels debug, create hero6.kml and hero6.gpx files)

   % python gopro2gpx.py -s -vvv samples/hero6.mp4 hero6

Arguments and options

% python gopro2gpx.py  --help
usage: gopro2gpx.py [-h] [-v] [-b] [-s] file outputfile

positional arguments:
  file           Video file or binary metadata dump
  outputfile     output file. builds KML and GPX

optional arguments:
  -h, --help     show this help message and exit
  -v, --verbose  increase output verbosity
  -b, --binary   read data from bin file
  -s, --skip     Skip bad points (GPSFIX=0)

• file: Gopro MP4 file or binary file with the gpmd dump.
• outputfile: Dump the GPS info into outputfile.kml and outputfile.gpx. Don't use extension.
• -v, -vv, -vvv: Verbose mode. First show some info, second dumps the gpmd track info a file called outputfile.bin and third (-vvv) shows the labels.
• -b: read the data from a binary dump fo the gpmd track istead of the MP4 video. Useful for testing, so I don't need to move big MP4 files.
• -s: skip "bad" GPS points. When GPSFIX=0 (no GPS satellite signal received) GPS data is unacurrate. Ignore these points.

How to get "accurate" GPS data in your GoPro [IMPORTANT]

Follow these steps:

1. Turn the camera on using the side mode button (Do Not use Quick Capture if GPS information is important to you)
2. Wait at least one minute (5-10 is best) before you start to record to allow the most satellite locks
3. Use the camera in the Frame mount and not the Super Suit (it will work in the Super Suit but might have a weaker signal)

Read the following thread for more info:

• GOPRO Forum

Technnical info

To get the gpmd data, we need to explore the MP4 container, and extract the stream marked as gpmd. The script does it automatically, but here is the output from ffprobe:

    % ffprobe GH010039.MP4

    The channel marked as gpmd (Stream #0:3(eng): Data: none (gpmd / 0x646D7067), 29 kb/s (default))
    In this case, the stream #0:3 is the required one (get the 3)

    Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'GH010039.MP4':
    Metadata:
        major_brand     : mp41
        minor_version   : 538120216
        compatible_brands: mp41
        creation_time   : 2019-02-10 10:59:19
    Duration: 00:00:21.80, start: 0.000000, bitrate: 60420 kb/s
        Stream #0:0(eng): Video: h264 (High) (avc1 / 0x31637661), yuvj420p(pc, bt709), 2704x1520 [SAR 1:1 DAR 169:95], 
        60173 kb/s, 50 fps, 50 tbr, 90k tbn, 100 tbc (default)
        Metadata:
        creation_time   : 2019-02-10 10:59:19
        handler_name    : GoPro AVC  
        encoder         : GoPro AVC encoder
        timecode        : 10:59:19:31
        Stream #0:1(eng): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 189 kb/s (default)
        Metadata:
        creation_time   : 2019-02-10 10:59:19
        handler_name    : GoPro AAC  
        timecode        : 10:59:19:31
        Stream #0:2(eng): Data: none (tmcd / 0x64636D74), 0 kb/s (default)
        Metadata:
        creation_time   : 2019-02-10 10:59:19
        handler_name    : GoPro TCD  
        timecode        : 10:59:19:31
        Stream #0:3(eng): Data: none (gpmd / 0x646D7067), 29 kb/s (default)
        Metadata:
        creation_time   : 2019-02-10 10:59:19
        handler_name    : GoPro MET  
        Stream #0:4(eng): Data: none (fdsc / 0x63736466), 12 kb/s (default)
        Metadata:
        creation_time   : 2019-02-10 10:59:19
        handler_name    : GoPro SOS  

We need the stream called in this clase, #0:3(eng) that is, the 0:3 stream:

        [...]
        Stream #0:3(eng): Data: none (gpmd / 0x646D7067), 29 kb/s (default)
        Metadata:
        creation_time   : 2019-02-10 10:59:19
        handler_name    : GoPro MET  
        [...]        

Extracting the binary GPS data from MP4

With this data, we can create a binary file with the gpmd data inside. The following command copy the stream 0:3 from the file GH010039.MP4 as raw, and stores it in GH010039.bin

%ffmpeg -y -i GH010039.MP4 -codec copy -map 0:3 -f rawvideo GH010039.bin

The binary looks like:

00000000: 44 45 56 43 00 01 14 A4 44 56 49 44 4C 04 00 01    DEVC...$DVIDL...
00000010: 00 00 00 01 44 56 4E 4D 63 01 00 0B 48 65 72 6F    ....DVNMc...Hero
00000020: 37 20 42 6C 61 63 6B 00 53 54 52 4D 00 01 05 AC    7.Black.STRM...,
00000030: 54 53 4D 50 4C 04 00 01 00 00 00 DB 53 54 4E 4D    TSMPL......[STNM
00000040: 63 01 00 0E 41 63 63 65 6C 65 72 6F 6D 65 74 65    c...Acceleromete
00000050: 72 00 00 00 53 49 55 4E 63 04 00 01 6D 2F 73 B2    r...SIUNc...m/s2
00000060: 53 43 41 4C 73 02 00 01 01 A2 00 00 4D 54 52 58    SCALs...."..MTRX
00000070: 66 24 00 01 00 00 00 00 00 00 00 00 3F 80 00 00    f$..........?...
00000080: 00 00 00 00 BF 80 00 00 00 00 00 00 3F 80 00 00    ....?.......?...
00000090: 00 00 00 00 00 00 00 00 4F 52 49 4E 63 01 00 03    ........ORINc...
000000a0: 59 78 5A 00 4F 52 49 4F 63 01 00 03 5A 58 59 00    YxZ.ORIOc...ZXY.
000000b0: 41 43 43 4C 73 06 00 DB FD 35 FF 2D 0D C7 FD 39    ACCLs..[}5.-.G}9
000000c0: FF 19 0D 87 FC CD FE F9 0D 4B FC 05 FE 45 0C AF    ....|M~y.K|.~E./
000000d0: FB B5 FD ED 0C 8F FB 65 FD E1 0C 6B FB 11 FE 6D    {5}m..{e}a.k{.~m
000000e0: 0C 47 FA E5 FE ED 0C 53 FA C5 FF 89 0C 87 FA C1    .Gze~m.SzE....zA
000000f0: FF F9 0C B3 FA AD 00 9F 0D 33 FA A9 00 B3 0D 6F    .y.3z-...3z).3.o
00000100: FA 95 00 B7 0D BB FA 65 00 C7 0E 3B FA 45 00 D7    z..7.;ze.G.;zE.W
00000110: 0E 73 FA 49 00 EF 0E A3 FA 25 00 E7 0E FB F9 FD    .szI.o.#z%.g.{y}
00000120: 00 E3 0E FF F9 E9 00 F3 0E FF F9 E9 00 E3 0E F3    .c..yi.s..yi.c.s
[...]

Testing

Sample videos are downloaded from here. I will try to put an original Gopro7 file later. The gps data is extracted from the .MP4 file. The gpx, kml and bin files are stored in the repo. Karma introduces a new way of read GPS information and time, based on SYST and GPRI labels. I did my best trying to parse it. Seems accurate. If you have some long files to do, please extract the raw data and send me them (see extracting data).

• fusion
• hero5
• hero6 (all the points)
• hero6 (only GPSFIX!=0)
• karma
• Gopro7

Status and future work

Currently, gopro2gpx generates hard-formatted kml, and a useful gpx file. But:

• Not all tags are parsed. see fourCC.skip_labels and fourCC.labels for more info.
• The are a little error detecting code.
• Karma drone GPS info has been infered from debug. Maybe the SYST label is parsed wrong.
• UNIT labels are parsed hardcoded.
• Need ffmpeg and ffprobe to extract the data.