Hi, , if you only want to "resize" your video, i think you can set width/height while transcoding :
vlc -vvv udp://@172.27.27.167:1234 --sout #transcode{width=800,height=450,acodec=mp4a,ab=96,channels=2,samplerate=48000}:rtp{dst=172.27.27.61,port=3001,mux=ts}