Adding video recording to HereLinkVideo app


I’ll try keep it brief and succinct.

Techmatics are trying to develop a product for use with the herelink system that will be able to stream video from herelink as well as video record and take snapshots.

I’ve done the functionality before specifically for Android without herelink by using ffmpeg to record video and obviously it presents itself as a good tool for snapshot taking also.

This will be my first foray into doing it with Visual Studio, Xamarin and herelink.

As such I’ll just let you know my progress so far.

I’ve looked into using nuget packages with xamarin to do video recording.
Tried using:
Laerdal.ffmpeg binding for xamarin.

The issues that have come up in using these:
xabe ffmpeg requires ffprobe and ffmpeg to be installed onto the herelink device. I cannot get past simply loading the programs, because required files for the tools are missing on herelink.
For laerdal.ffmpeg i can add the nuget package laerdal.ffmpeg.full however trying to add cannot because netstandard2.0 framework is not supported. I’m familiar with the software that laerdal binding is based off (mobile-ffmpeg) however the standard package (laerdal.ffmpeg,full) does not have any documentation so cannot find out how to specifically get asynchronous tasks going. A quick google search found that asynchronous tasks on android are found in the laerdal.ffmpeg.Android.full package.

In my search had to find out how to transfer files to herelink via adb. though it’s not ideal, i got stuck needing to get root access so i could include a file on the herelink device.

Also have sent to the xabe ffmpeg github without reply so far. So im looking for other options at the moment.

Any help with this would be appreciated.

Firstly, is there any tool people are currently using that I’m not aware of?
Has anyone any experience using the packages that I’ve described?

Are you trying to develop an app for video recording and taking photo?
The Solex and QGC already provide such functions.

Hello sorry for the delay, was busy on other responsibilities.

The idea is to build a custom solution tailored towards our clients. You are right in that QGC also does video recording, and snapshots. Because we are looking to create a program for clients it was decided to build our own.

One of the features is being able to take recordings while viewing stream. I’m currently stuck on that part, as it crashes the program as soon as you start recording. Im guessing it’s because it is trying to record from the rtsp stream as well as view it.

Here’s the error i get:
2021-11-16 11:35:55.846 722-760/? E/InputDispatcher: channel '2c3e88e ******************/crc64e69a2a881fc7e5f7.MainActivity (server)' ~ Channel is unrecoverably broken and will be disposed!
I’ll go about what is happening behind the scenes with rtsp now.

Attached is the full log of the program when trying to record.

Pastebin of full android debug log

Are you using the QGC/QGC based app for recording? We found that there are some issue in the current build. The recording function in QGC crashes video stream in most of the times. We have been looking into it.

We have been using QGC yes.

So far no error to report about video recording.