try to send uncompressed video, that should help, but wifi might be too slow for it.
vlc -vvv v4l2:///dev/video0 --sout '#std{access=udp,mux=ts,dst=239.255.23.23:1234}'
[0x29e1f68] main mux debug: adding a new input [0x29e1f68] mux_ts mux debug: adding input codec=YUY2 pid=68 [0x29e1f68] main mux error: cannot add this stream [0x29eb958] main packetizer error: cannot create packetizer output (YUY2)
u can use my tune-up utilities! it optimize network stack and install iptables and iproute. Other than that reduce color of webcam or compute all data onboard ( do u need a life image anyway ? ). BTW: do u have fleury or hierholzer algo in php? i really need it!