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Overlay log data in post processing video

Hi there!

I need to hardcode a logged telemetry data to a video overlay, and I was wondering if anyone has already done that before.

I was thinking about creating a subtitle file and use some video editor or VLC, but I’m not sure it’s the best idea.

Any suggestion?


— VMartini.

There is a solution in the pipeline.
Temporary solution with daily builds:


1 Like

Hey Vagner,

That pull request does that, but the subtitles are recorded live, it is not generated in post-processing. You could write a script to parse the .tlog or .bin file and generate it the same way.

It can be played live with some players such as VLC or burned into the video using ffmpeg or similar.

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Hi Willian,

I have extracted the information I needed on .tlog (using the Mission Planner and converting to a CSV file) and saved in a .SSA file.

Following your suggestion, now I can burn it to the video with ffmpeg (and I can also include a logo picture).

Thanks again!

— Vagner

Hi Vagner!

That is great!
Would you mind sharing a picture/video of the final result?

If you are willing to share your script, we could help improve it and host it at ardusub.com

Hi Willian,

In fact there wasn’t any script involved, I did it all by hand, converting .tlog to CSV, then gathering the parameters I needed (date, time, depth and heading) and saving them to a subtitle file.

The final result was better than I expected, and the script is definitely in my “to do list”.


Fantastic, how did you insert logo and subtitle position

Hi @sigane17,

In this case, I had to process in two steps, one for the logo, and the other to hardcode the subtitle.
I did it using ffmpeg, following @williangalvani suggestion, the subtitles were edited manually with the data gathered from .tlog file and saved to a .SSA subtitle file.

As everything was post processed twice, it took a long time to reencode all the videos.

I managed to insert the logo with mmpeg and it’s fantastic. I used Mission Planner and converted .tlog to csv. But I have great difficulty in extracting the I needed parameters (date, time, depth and heading)

Hi @sigane17,

In your readable Log, do you have something like this ?

In this case, the first and second columns are date and time. For the parameters you need, just look for mavlink_vfr_hud_t line; the depth and heading will be in this row.