Does scrcpy support YUYV 422 format?

- [ ] I have checked that a similar [feature request](https://github.com/Genymobile/scrcpy/issues?q=is%3Aopen+is%3Aissue+label%3A%22feature+request%22) does not already exist.

**Is your feature request related to a problem? Please describe.**
I use scrcpy --v4l2-sink to project screen to virtual camera. ffplay work well, but unity can not work well with the virtual camera. It seems that unity does not support YUV 420. So I want to know whether scrcpy support YUYV 422 format?

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Start by examining scrcpy's --v4l2-sink path and how its current YUV 420 output is passed to the virtual camera. The issue names no source files or tests, so first identify the relevant video-output entry point and determine whether YUYV 422 is supported; done means Unity can consume the resulting virtual-camera stream.

Written by the indexing model from the issue text.