只為了預設啟用h264，但書有一大堆
Only the "Graphics Pipeline" extension of the RDP protocol is implemented for video streaming. This extension allows using H.264 for video streaming, but it means only clients supporting that extension are supported.
H.264 encoding is done using hardware encoding if possible, but currently we only support using VAAPI for this. Most notably this means hardware encoding on NVidia hardware can not be used and software encoding will be used instead. Additionally, on certain hardware there are limits to what size of frame can be encoded by the hardware. In both cases, encoding will fall back to software encoding.