I am using a GSI on my phone and when I try to use scrcpy I get this output:
The solution was simple (so simple, in fact, that I am angry at myself for not having thought of it sooner / finding it sooner). Execute this in your Terminal:
scrcpy --list-encoders
Then try codec after codec until one works, and use that one from now on. It really is that simple. For my Unihertz Titan Slim with a LinageOS 20 GSI it was:
scrcpy --video-codec=h264 --video-encoderc2.android.avc.encoder' --audio-codec=opus --audio-encoder='c2.android.opus.encoder' --forward-all-clicks
More readable:
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