How to livestream to Twitch and YouTube at the same time using ffmpeg and OBS Studio on a single Windows or Linux computer
I'm a big fan of OBS Studio, and I've recently started learning how to use ffmpeg for transcoding and remuxing my videos. One thing that has bugged me is that current versions of OBS Studio can only stream to one streaming service at a time (one RTMP server). There are services like restream.io that get around this, but you're basically paying them for a little bit of CPU/GPU time and some added latency to your stream, and maybe only getting combined chat in return. Well, it just so happens that with a single ffmpeg command line invocation, you can output to multiple files and streaming services at once with very little overhead. Another benefit of ffmpeg over OBS Studio is that it supports more encoders such as hevc_amf which is the hardware H.265 encoder for AMD video cards. OBS Studio currently only supports h264_amf via the Advanced output mode. Strangely, OBS Studio has an included version of ffmpeg but the list of encoders it has does not include any AMD encoders, o