Adjusting video to deal with low bandwidth

[jonsaken]

I promised to post this question during the last telecon.

From where we will be launching, a good internet connection is simply not going to be available.  Like much of rural America, there is only one provider in the area (Frontier) and their service is rather poor DSL.  We can expect 1.5 Mb at best.

So we were looking for a way in reduce the requirements on the video streaming.  Using a lower FPS and/or descreasing the resolution of the video.  Can anyone give us a guidance on how to do this?

Thanks.  We ARE looking into trying a temporary, satellite-based option, but that may not work out.
 

[Skylar MSGC]

One of the big things is to adjust the bitrate of the video. To adjust this you need to goto

/opt/stream/bin/

you can use cd (location of folder) to get there

then the file that you are looking for is:

picam-rtsp-server.sh


When you are modifying this file look for:

BAUDRATE = xxxx

Currently it should be something like 3000000 which is 3Mb/s

I would recommend taking this down to something like 1500000 for 1.5Mb/s

This should help in getting your data usage down.

[joshnelson_MNSGC]

Could this bitrate be changed during a flight? For example, if we were to ssh into the pi through the Ubiquiti connection and manually change the bitrate in the file, would this change the bitrate without having to power cycle?

If so, this would be a great way to adjust video resolution on the fly in the event of poor streaming ability.

[Skylar MSGC]

That willchange the bitrate when you restart the RPi after changing that. The file is called on boot up and is stored in the RPi memory until that process is killed.

So I would recommend restarting the RPi after changing it, being asthis is the easiest and maybe the quickest way to implement the changes.

Just don't change any network settings.

[irowe]

Does anyone know if this has been implemented in the August update, or does the bitrate have to be manually changed?

cc. Skylar MSGC

[Skylar MSGC]

The bit rate on the new image is at 2Mb/s instead of the 3 that the previous image was set to. You can check this in the /opt/stream/bin/picam-rtsp-server file.