Screen capture show mirrored in fakecamera script

[MurzNN]

I successfully start fakecamera script on Ubuntu 19.04 with KDE environment, and Firefox shows the one screen, but the image from fake webcam is mirrored in Firefox! How can I mirror it back?

[MurzNN]

adding -vf hflip argument to ffmpeg launch command solves the problem, is this right solution? Why in my setup it is mirrored by default?

P.S. And here are Firefox issues about dual monitors share problem:
https://bugzilla.mozilla.org/show_bug.cgi?id=1412333
https://bugzilla.mozilla.org/show_bug.cgi?id=1552456

[BigB84]

I have similar problem with firefox, jitsi and beta.jitsi
OS: xen-based virt. Debain.

In webcamoid screen is shared properly. In Jitsi it is flipped vertically, in Jitsi beta it's mirrored.
I fixed it same as @MurzNN by -vf hflip.
It seems it's jitsi problem however maybe we could add such option while executing script, as it's useful?

I mean after . fakecamera :

• Which screen you want to share (..)
• Do you want to append transform fix?

Alternatively, we could add information to docs, as it'd be much faster to fix the problem than searching for it in issues or reading ffmpeg/v4l2 docs. Of course that's how we should search but I thought about less technical people that have just come from windows or they don't know how to use search engine ;)