New video overlay option in QGroundControl

Video overlay is one of our most requested features among ArduSub and BlueRov2 users, and it’s been the topic of many discussions here in the past.

I’m happy to leak that the first support for this feature has recently been merged into the QGroundControl development branch (not stable). The support comes in the form of a subtitle file that will update the telemetry values at 1Hz. More information on the decision to use subtitles is explained in the proposal for the feature, and in @williangalvani’s pull request to add the feature.

Your knight in dark armor, @williangalvani, slayed the code to create the subtitle files. In perhaps an even more gallant effort, he is also working on documentation on how to use the subtitle files with common media players, and how export a single video file with the overlay ‘burned in’. We will update here as that develops.

If you would like to ‘beta test’ it, the feature can be tested today if you download the daily build from qgroundcontrol’s website. Note that this build is updated continuously, and is not considered stable. You should not attempt to use it for any critical work or applications.


great work @williangalvani!!!

That’s great! I think it will be a really useful feature!!! Is it also possible to input external data to overlay, such as positioning coordinates?

It currently does not support arbitrary data, but if you are use waterlinked or injecting GPS data to the ROV from another source, those can be used.


Thanks for the report.

It is great to see some progress.

Can I get the link of the software update for me to download and install?


Hi @luis.chavez, it is available from the qgroundcontrol website. I won’t link it here as it is a beta test, so we want to limit the amount of technical support stemming from this right now.

Just wanting to be clear on how it works…you could run this beta version of QGC and everything would hypothetically be the same, except when you save video through QGC, it would have this overlay applied to it? Further, you could pipe the video feed from GQC into something like VLC and the overlay would be visible?

and everything would hypothetically be the same

No, there have been extensive changes in other areas of the code as well. The download link is continuously updated as the code changes. It might generally look/work the same, but this should not be the expectation for the daily build because it is not guaranteed.

No. It works the same way as it does today, only a separate/independent subtitle file is saved in addition to the video. When you open the saved video file later, the subtitles will appear on top.

Ahhh ok, so everything works the same(excluding other QGC changes), except it just saves a .sub file with the corresponding file name. Sounds like a nice feature. Have you guys set a date, or rough estimate, for the next BR QGC release?

Hi Folks, briliant adition to QGC, exactly what’s needed. Could someone out-there please advise on how to install this patch as I’m keen to try it.

Thanks Roofus


Take a look in the official documentation and the last daily builds. Remember that such builds and features are not stable and not ready for release yet.

Thanks Patrick, do you have any idea when a stable version will be released? We have a subsea inspection contract starting soon and would like to include our BlueROV 2, Heavy however not having overlay would limit its use as overlay is a must. Of course we could try the beta version but as you mentioned its not stable yet so i would prefer to wait which i hope will not be long?

Thanks again

Hi all ,

Has anybody tested this new function ?

I have downloaded the last daily build but QGC is recording only the video file as usual , without the additional overlay subtitles file …

Any suggestion ?

Many thanks,


do you have any idea when a stable version will be released

There is no release date or a time period to inform, it’s is in development.

From the documentation, you should use a player that supports SubStation Alpha subtitle format, try with the last version of VLC. If it’s not working, please open an issue here with the necessary information to reproduce. Remember that since it’s not a stable release, bugs can happen.

I can’t access the daily build site, anyone have the same problem? Is there an alternative site for download?

daily builds

@uwvid The Windows daily download worked for me, for which OS were you trying to get?

I can’t access the page, Safari and Google Chrome can’t find the server. However, I managed to access through my phone browser. I downloaded the software and transferred to my computer.

No overlay video in the last daily build (25 décembre 19). I have to change parameters ??

@JeanBenoit Check if there are .ass (Advanced SubStation alpha) files in the same folder as the videos. Those are the files with the overlay. Not all players support that, I personally like using VLC

@williangalvani Hi,
On the new daily build the .ass is here !! But VLC don’t read the .ass. They have same name, in same folder.
A special parameters on VLC / QGC ??