Decode GPS data from mp4

Started by programandoconro, May 23, 2022, 03:22:56 AM

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programandoconro

Hello, I am new to this Forum.

I want to decode an extracted gps information from a video

I run exiftool -ee -V3 -b -GPSDataList -GPS drive_record_1.MP4 > test.txt

and obtained this kind of response:


GPSDataList = .......-...Cf\.YS..n....................2........%L....d../.t..D.(..Z[snip]
  | - Tag 'gps ' (248 bytes):
  |  290fed7: 00 00 01 01 00 00 00 1e 00 17 fd f0 00 00 80 00 [................]
  |  290fee7: 00 2d 1d 8c 00 00 80 00 00 43 66 5c 00 00 80 00 [.-.......Cf\....]
  |  290fef7: 00 59 53 1c 00 00 80 00 00 6e f1 94 00 00 80 00 [.YS......n......]
  |  290ff07: 00 83 f5 cc 00 00 80 00 00 99 f9 c0 00 00 80 00 [................]
  |  290ff17: 00 af e4 d0 00 00 80 00 00 c4 fe b0 00 00 80 00 [................]
  |     [snip 168 bytes]
---- Extract Embedded ----
Type='gps ', Sample 1 of 30 (32768 bytes)
  17fdf0: 00 00 80 00 66 72 65 65 47 50 53 20 6c 00 00 00 [....freeGPS l...]
  17fe00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [................]
  17fe10: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [................]
  17fe20: 59 57 4b 4a 47 50 53 00 00 00 00 00 01 00 00 00 [YWKJGPS.........]
  17fe30: fc ff ff ff 41 00 00 00 07 00 00 00 12 00 00 00 [....A...........]
    [snip 32688 bytes]
Type='gps ', Sample 2 of 30 (32768 bytes)
  2d1d8c: 00 00 80 00 66 72 65 65 47 50 53 20 6c 00 00 00 [....freeGPS l...]
  2d1d9c: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [................]
  2d1dac: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [................]
  2d1dbc: 59 57 4b 4a 47 50 53 00 ff ff ff ff ff ff ff ff [YWKJGPS.........]
  2d1dcc: f9 ff ff ff 41 00 00 00 07 00 00 00 12 00 00 00 [....A...........]
    [snip 32688 bytes]
...
...



I want to extract the gps information, specially, longitude, latitude and altitude.

Is there a command to try to decode this information?

Here is the .mp4 file: https://drive.google.com/file/d/1xRpZQ46BybiSRRsAuy9zYD2PIDR6cqti/view?usp=sharing

Thanks in advance.




programandoconro

If it helps, this is the camera model: ミツバ EDR-21Gα.

And I think the name of the file is important for decoding:

This was the original name: F_20190101000008_20210224161853_N.MP4

programandoconro

Also, here is the software use to view the gps position https://www.mskw.co.jp/motorcycle/edr/support/

StarGeek

Phil will probably take a look at the file when he get's a chance, but it may not be possible to decode the data.  Running this command
exiftool -G1 -a -s -ee3 -gps* Y:\!temp\ccc\20211216081802_001314A.MP4
results in wildly inaccurate values
[QuickTime]     GPSDateTime                     : 2021:12:16 08:18:02Z
[QuickTime]     GPSLatitude                     : 18304 deg 10' 50.07" N
[QuickTime]     GPSLongitude                    : 279 deg 41' 46.54" W
[QuickTime]     GPSSpeed                        : 0.1482
[QuickTime]     GPSTrack                        : 180


It may be related to this post in which the numbers are obfuscated.
* Did you read FAQ #3 and use the command listed there?
* Please use the Code button for exiftool code/output.
 
* Please include your OS, Exiftool version, and type of file you're processing (MP4, JPG, etc).

programandoconro

@StarGeek thank you for kind reply and explanation. I hope Phil takes a look of it. I also suspect the numbers are obfuscated, do not any about decoding but because the software did not accept any file name, I believe the name of the file may some information for the decoding.

I really want to wait and see if Phil can give us more clues.

Thank you.




programandoconro

Quote from: StarGeek on May 23, 2022, 11:07:34 AM
Phil will probably take a look at the file when he get's a chance, but it may not be possible to decode the data.  Running this command
exiftool -G1 -a -s -ee3 -gps* Y:\!temp\ccc\20211216081802_001314A.MP4
results in wildly inaccurate values
[QuickTime]     GPSDateTime                     : 2021:12:16 08:18:02Z
[QuickTime]     GPSLatitude                     : 18304 deg 10' 50.07" N
[QuickTime]     GPSLongitude                    : 279 deg 41' 46.54" W
[QuickTime]     GPSSpeed                        : 0.1482
[QuickTime]     GPSTrack                        : 180


It may be related to this post in which the numbers are obfuscated.

I tried running the command you suggested but gives an empty response. I tried in windows, wsl and linux. I believe in windows I am using the latest version(12.41) and in linux 12.40.

StarGeek

In Linux, make sure you put quotes around -gps*, as the asterisk is a special character. Something to do with file globbing, but I can never find a page which properly explains it in this context.

Otherwise, I don't know why it wouldn't work for you.  Here's the full output on PasteBin, 1500+ lines.
* Did you read FAQ #3 and use the command listed there?
* Please use the Code button for exiftool code/output.
 
* Please include your OS, Exiftool version, and type of file you're processing (MP4, JPG, etc).

programandoconro

@StartGeek, thank you for the snippet !!

Still does not work on Linux or Windows but is nice step to see the resulting data, even if obfuscated.

I do not know if helps but, these are the actual coordinates:


"Date","Time","Latitude","Longitude","Altitude"
"2021-02-24","07:19:23",35.678787231445313,139.77952575683594, 0
"2021-02-24","07:19:24",35.678836822509766,139.779541015625, 0
"2021-02-24","07:19:25",35.678882598876953,139.779541015625, 0
"2021-02-24","07:19:26",35.678920745849609,139.77960205078125, 0
"2021-02-24","07:19:27",35.678951263427734,139.77960205078125, 0
"2021-02-24","07:19:28",35.678989410400391,139.77964782714844, 0
"2021-02-24","07:19:29",35.679023742675781,139.77967834472656, 0
"2021-02-24","07:19:30",35.679065704345703,139.77969360351563, 0
"2021-02-24","07:19:31",35.679111480712891,139.77972412109375, 0
"2021-02-24","07:19:32",35.679176330566406,139.77976989746094, 0
"2021-02-24","07:19:33",35.679244995117188,139.77980041503906, 0
"2021-02-24","07:19:34",35.679313659667969,139.77984619140625, 0
"2021-02-24","07:19:35",35.679397583007813,139.77992248535156, 0
"2021-02-24","07:19:36",35.679485321044922,139.77995300292969, 0
"2021-02-24","07:19:37",35.679561614990234,139.77999877929688, 0
"2021-02-24","07:19:38",35.679645538330078,139.78005981445313, 0
"2021-02-24","07:19:39",35.679721832275391,139.78010559082031, 0
"2021-02-24","07:19:40",35.6798095703125,139.78013610839844, 0
"2021-02-24","07:19:41",35.679893493652344,139.78018188476563, 0
"2021-02-24","07:19:42",35.679969787597656,139.78022766113281, 0
"2021-02-24","07:19:43",35.6800537109375,139.78028869628906, 0
"2021-02-24","07:19:44",35.680122375488281,139.78033447265625, 0
"2021-02-24","07:19:45",35.680187225341797,139.78036499023438, 0
"2021-02-24","07:19:46",35.680255889892578,139.78041076660156, 0
"2021-02-24","07:19:47",35.680320739746094,139.78044128417969, 0
"2021-02-24","07:19:48",35.680377960205078,139.78045654296875, 0
"2021-02-24","07:19:49",35.680427551269531,139.780517578125, 0
"2021-02-24","07:19:50",35.680477142333984,139.78053283691406, 0
"2021-02-24","07:19:51",35.680522918701172,139.78056335449219, 0
"2021-02-24","07:19:52",35.680568695068359,139.78059387207031, 0

StarGeek

Maybe it is an edited version of the file you uploaded?  Or maybe you have a older version of exiftool somewhere on your drive that is called instead of the one you think is called.  Try exiftool -ver to see the version and where exiftool on Windows to see possible locations.  I think you would use which instead on Linux.
* Did you read FAQ #3 and use the command listed there?
* Please use the Code button for exiftool code/output.
 
* Please include your OS, Exiftool version, and type of file you're processing (MP4, JPG, etc).

programandoconro

QuoteMaybe it is an edited version of the file you uploaded?  Or maybe you have a older version of exiftool somewhere on your drive that is called instead of the one you think is called.  Try exiftool -ver to see the version and where exiftool on Windows to see possible locations.  I think you would use which instead on Linux.

@StarGeek, thanks again for your suggestions.

exiftool -ver returns 12.41 in Windows, 11.88 in WSL(Ubuntu 20) and 12.40 in Linux(Ubuntu 22). I believe the file is the same that I shared.

Thanks for your kind help. I do not know if you have any more clues.


Phil Harvey

I get the same thing as StarGeek when looking at this file.

Unfortunately the coordinates seem to be obfuscated as StarGeek mentioned, and as yet I don't know how to decode them. :(

- Phil
...where DIR is the name of a directory/folder containing the images.  On Mac/Linux/PowerShell, use single quotes (') instead of double quotes (") around arguments containing a dollar sign ($).

programandoconro

Phil, thank you for you kind reply. I really appreciate it. Please have a wonderful day!  :D