Can't concat Garmin DashCam videos with telemetry (GPS data)

[jmlgeo]

Hi,

I have a Garmin 66W dashcam for my work (street mapping surveyor) which produces several 1min. MP4 videos of my journey (60 min. = 60 videos). All these videos have telemetry data on it as metadata (GPS location, speed, etc...).

I want to concatenate every 5 files excluding the audio but preserving the video and the telemetry in the metadata.

What I have tried so far:

• Export GPS information as GPX file (result: successful)

exiftool -p gpx.fmt -ee X:\video_place\videos_1m\GRMN0005.mp4 > GRMN0005.gpx

• Merge MP4 videos as a single MP4 video (result: partially successful)

ffmpeg -f concat -safe 0 -i X:\video_place\videos_1m\mylist.txt -c copy X:\video_place\videos_1m\GRMN0005to0011.mp4

When I use above command on ffmpeg I loose all my telemetry data.

I tried in several different ways for days, searching on several forums, I even tried to export all GPS data from each single 1min. file merge them, and them merge the videos and put the telemetry back.

The ffprobe output of my 1min. video is as following:

Metadata:
major_brand : avc1
minor_version : 0
compatible_brands: avc1isom
creation_time : 2021-07-26T17:08:23.000000Z
Duration: 00:01:00.06, start: 0.000000, bitrate: 19553 kb/s
Stream #0:0(eng): Video: h264 (Main) (avc1 / 0x31637661), yuv420p(tv, bt709), 1920x1080, 19182 kb/s, 29.97 fps, 29.97 tbr, 30k tbn (default)
Metadata:
creation_time : 2021-07-26T17:08:23.000000Z
handler_name : Ambarella AVC
vendor_id : [0][0][0][0]
encoder : Ambarella AVC encoder
Stream #0:1(eng): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, mono, fltp, 128 kb/s (default)
Metadata:
creation_time : 2021-07-26T17:08:23.000000Z
handler_name : Ambarella AAC
vendor_id : [0][0][0][0]
Stream #0:2(eng): Subtitle: mov_text (text / 0x74786574), 0 kb/s (default)
Metadata:
creation_time : 2021-07-26T17:08:23.000000Z
handler_name : Ambarella EXT

I have tried as well with following code, but none of them seems to work:

ffmpeg -f concat -safe 0 -i X:\video_place\videos_1m\mylist.txt -c copy -scodec copy X:\video_place\videos_1m\GRMN0005to0011_scodec.mp4

ffmpeg -f concat -safe 0 -i X:\video_place\videos_1m\mylist.txt -c:s copy -c:v copy X:\video_place\videos_1m\GRMN0005to0011.mp4

ffmpeg -f concat -safe 0 -i X:\video_place\videos_1m\mylist.txt -c copy -c:s mov_text X:\video_place\videos_1m\GRMN0005to0011.mp4

What am I missing?

[pcspeak]

Hi jmlgeo.
As there have been no responses, could you upload 3 of 1 minutes clips to somewhere. Straight from the camera, no alterations.
I wouldn't mind having a swing at it. I'm running Win10 & testing Win11 beta.

Cheers.