What is MistProcAV?

MistProcAV is a stream process within MistServer. Stream processes are created to edit, modify or change streaming tracks and data in some way. In the case of MistProcAV that is usually video quality/codec changes, however audio can also be edited.

Under the hood, MistProcAV uses libAV, which is a library used for most encoding tasks - perhaps to the point where we should call it the library. The advantages to using MistProcAV are that due to it being directly within the MistServer codebase it's much lower latency and has a much higher performance when ran. Some of the cons however are that you need to build for the correct OS and it comes with a different license. Therefore we cannot add it to just any build of MistServer (though we are looking into upgrades which would allow this).

Of course another aspect to MistProcAV is that it's much more limited in comparison to other tools which use this library such as FFmpeg. While being more limited is never fun, it is much easier in making a choice in what to use as you're only allowed to use settings that work well within MistServer. As an example: we've removed Bframes as stream processes are only meant for live streams and use of B-frames often makes no sense when it comes to live and low latency streaming.

Getting MistProcAV within your MistServer

Currently the easiest and best way would be to install the libav dependencies and [compile your own with AV enabled](https://docs.mistserver.org/mistserver/installation/compile). You only need to add the compile flag -DWITH_AV=true for this.

Missing a specific codec or want some help setting things up? Feel free to contact us.