I ran into a huge problem with AMD GPUs and 4.27.1 - it doesn’t work at all.
The engine just crashes/quits unexpectedly once the viewer connects in the browser:
The last line in the Engine’s log file is:
LogEncoderAMF: Error: Amf failed to get frame QP.
See [this zip][2] for the whole crash report incl. full log.
This issue happens both with from the official PixelStreaming Demo with the official UE 4.27.1 Windows binaries from the launcher, and with our own project and self-compiled UE 4.27.1.
I could reproduce the problem with both my local Radeon RX580 (driver version 21.10.2, Win10) and on an Amazon EC2 “g4ad.xlarge” Instance with a AMD Radeon Pro V520 GPU (driver version 27.20.11025.4019 from 4/14/2021, the latest driver Amazon offered when I set the VM up; Windows Server 2019).
I want to explicitly point out again that UE4 PixelStreaming in 4.27.1 does NOT work with the most affordable Amazon GPU instance type - in my opinion this is a very serious problem.
PixelStreaming did still work in 4.26 (both with my local RX580 and on the EC2 instance), so this seems to be a regression - and unfortunately 4.26 isn’t really usable either because it doesn’t work with newer versions of Chrome or MS Edge (it does work when connecting with Firefox though).
With nvidia GPUs, PixelStreaming works with both tested projects, on both 4.26 and 4.27, so the issue seems AMD-specific.
Are there any workarounds for this problem?
Update: One thing I forgot to mention: I’m starting the engine with:
PixelStreamingDemo.exe -AudioMixer -PixelStreamingIP=localhost -PixelStreamingPort=8888 -RenderOffScreen -ForceRes -ResX=1920 -ResY=1080
Not setting -RenderOffScreen doesn’t make it work either, but it shows that everything runs normally and is rendered normally until a viewer connects (then the engine crashes more or less immediately).