RDS Live Now Playing Data with Icecast and MPV

[chodgetts]

I am running MPV to get my radio station stream from an icecast server - struggled to get HLS metadata from an adts segment to update out of ffmpeg or mpv, so this is what I am doing to get icecast data to rds:

---

cat ~/.config/systemd/user$ cat stream.service
`
[Unit]
Description=Radio Aotearoa HLS Live Stream
After=pipewire-pulse.service

[Service]
Type=simple
ExecStart=/usr/bin/mpv --no-video --audio-device=pulse/AFProcessor --volume=100 --input-ipc-server=/tmp/mpvsocket --script-opts=osc=no https://[insert-your-icecast-url-here]
Restart=always
RestartSec=5

[Install]
WantedBy=default.target
`

---

cat :~/.config/systemd/user$ cat rds_bridge.service
`[Unit]
Description=RDS Metadata Bridge
After=stream.service

[Service]
Type=simple
ExecStart=/usr/bin/python3 /usr/local/bin/rds_bridge.py
Restart=always

[Install]
WantedBy=default.target`

---

cat /usr/local/bin/rds_bridge.py

`import socket
import json
import subprocess
import time

def send_to_rds(text):
# Truncate and strip whitespace/newlines
clean_text = text.strip()
# Use the proven rds95 syntax: rt1=Text
payload = f'rt1={clean_text[:64]}'.encode('utf-8')
try:
sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
sock.sendto(payload, ("127.0.0.1", 5000))
sock.close()
except Exception as e:
print(f"UDP Error: {e}")

def get_mpv_title():
try:
cmd = 'echo '{ "command": ["get_property", "media-title"] }' | socat - /tmp/mpvsocket'
result = subprocess.check_output(cmd, shell=True).decode('utf-8')
data = json.loads(result)
return data.get("data")
except:
return None

last_title = ""
print("Bridge active. Watching for metadata...")

while True:
current_title = get_mpv_title()
if current_title and current_title != last_title:
print(f"New Track: {current_title.strip()}")
send_to_rds(current_title)
last_title = current_title
time.sleep(10) # 10-second polling interval`