ICOM VE-PG4 RoIP Gateway Multicast Communication PoC code

send.py

#!/usr/bin/env python3
"""
VE-PG4 RoIP Gateway 1 (239.255.255.1:22510, G.711u) 로 1초간 1kHz 비프 송신.
"""
import socket, struct, time, math, sys

MCAST = '239.255.255.1'
PORT  = 22510
SSRC  = 0xCAFEBABE
TTL   = 32                   # 라우터 한두 홉 넘기 위해

IFACE_IP = sys.argv[1] if len(sys.argv) > 1 else None

def linear_to_ulaw(sample: int) -> int:
    BIAS, CLIP = 0x84, 32635
    sign = 0x80 if sample < 0 else 0
    if sample < 0: sample = -sample
    if sample > CLIP: sample = CLIP
    sample += BIAS
    val = (sample >> 7) & 0xFF
    seg = 0
    while val > 1 and seg < 7:
        val >>= 1; seg += 1
    return (~(sign | (seg << 4) | ((sample >> (seg + 3)) & 0x0F))) & 0xFF

ULAW_TBL = bytes(linear_to_ulaw(s if s < 32768 else s - 65536) for s in range(65536))

s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
s.setsockopt(socket.IPPROTO_IP, socket.IP_MULTICAST_TTL, TTL)
if IFACE_IP:
    s.setsockopt(socket.IPPROTO_IP, socket.IP_MULTICAST_IF, socket.inet_aton(IFACE_IP))
    print(f"outgoing iface = {IFACE_IP}")

print(f"sending 1s of 1 kHz beep -> {MCAST}:{PORT}  TTL={TTL}  SSRC=0x{SSRC:08x}")

seq, ts = 0, 0
for f in range(50):
    pcm = bytearray()
    for i in range(160):
        sample = int(8000 * math.sin(2 * math.pi * 1000 * (f*160 + i) / 8000))
        pcm += struct.pack('<h', sample)
    ulaw = bytes(ULAW_TBL[pcm[i*2] | (pcm[i*2+1] << 8)] for i in range(160))
    rtp = struct.pack('!BBHII', 0x80, 0x80 if seq == 0 else 0x00,
                      seq & 0xFFFF, ts & 0xFFFFFFFF, SSRC)
    s.sendto(rtp + ulaw, (MCAST, PORT))
    seq += 1; ts += 160
    time.sleep(0.020)

print("done")

Send beep for 1 second.
You should set up the bridge for send this signal to other radio.