ffmpeg output pipeing to named windows pipe
It seems like the problem can be solved by adding the -y option to the ffmpeg command and specifying a buffer size for the pipe.
My ffmpeg command (see aergistal's comment why I also removed the -pass 1 flag): -y -f rawvideo -vcodec rawvideo -video_size 656x492 -r 10 -pix_fmt rgb24 -i \\.\pipe\to_ffmpeg -c:v libvpx -f webm \\.\pipe\from_ffmpeg
And defining the named pipe as follows:
p_from_ffmpeg = new NamedPipeServerStream(pipename_from, PipeDirection.In, 1, PipeTransmissionMode.Byte, System.IO.Pipes.PipeOptions.WriteThrough, 10000, 10000);