feature/network_audio (#6)

- make the device work standalone with webui
- add support for aes67
- may more things

Co-authored-by: pstruebi <struebin.patrick.com>
Reviewed-on: https://gitea.pstruebi.xyz/auracaster/bumble-auracast/pulls/6

src/auracast/multicast_script.py

@@ -0,0 +1,155 @@
+"""
+multicast_script
+=================
+
+Loads environment variables from a .env file located next to this script
+and configures the multicast broadcast. Only UPPERCASE keys are read.
+
+Environment variables
+---------------------
+- LOG_LEVEL: Logging level for the script.
+  Default: INFO. Examples: DEBUG, INFO, WARNING, ERROR.
+
+- INPUT: Select audio capture source.
+  Values:
+    - "usb" (default): first available USB input device.
+    - "aes67": select AES67 inputs. Two forms:
+        * INPUT=aes67            -> first available AES67 input.
+        * INPUT=aes67,<substr>   -> case-insensitive substring match against
+          the device name, e.g. INPUT=aes67,8f6326.
+
+- BROADCAST_NAME: Name of the broadcast (Auracast BIG name).
+  Default: "Broadcast0".
+
+- PROGRAM_INFO: Free-text program/broadcast info.
+  Default: "Some Announcements".
+
+- LANGUATE: ISO 639-3 language code used by config (intentional key name).
+  Default: "deu".
+
+- PULSE_LATENCY_MSEC: Pulse/PipeWire latency hint in milliseconds.
+  Default: 3.
+
+Examples (.env)
+---------------
+LOG_LEVEL=DEBUG
+INPUT=aes67,8f6326
+BROADCAST_NAME=MyBroadcast
+PROGRAM_INFO="Live announcements"
+LANGUATE=deu
+"""
+import logging
+import os
+import time
+from dotenv import load_dotenv
+from auracast import multicast
+from auracast import auracast_config
+from auracast.utils.sounddevice_utils import list_usb_pw_inputs, list_network_pw_inputs
+
+
+if __name__ == "__main__":
+    
+    logging.basicConfig( #export LOG_LEVEL=DEBUG
+        level=os.environ.get('LOG_LEVEL', logging.INFO),
+        format='%(module)s.py:%(lineno)d %(levelname)s: %(message)s'
+    )
+    os.chdir(os.path.dirname(__file__))
+    # Load .env located next to this script (only uppercase keys will be referenced)
+    load_dotenv(dotenv_path='.env')
+    
+    os.environ.setdefault("PULSE_LATENCY_MSEC", "3")
+  
+    usb_inputs = list_usb_pw_inputs()
+    logging.info("USB pw inputs:")
+    for i, d in usb_inputs:
+        logging.info(f"{i}: {d['name']}  in={d['max_input_channels']}")
+  
+    aes67_inputs = list_network_pw_inputs()
+    logging.info("AES67 pw inputs:")
+    for i, d in aes67_inputs:
+        logging.info(f"{i}: {d['name']}  in={d['max_input_channels']}")
+    
+    # Input selection (usb | aes67). Default to usb.
+    # Allows specifying an AES67 device by substring: INPUT=aes67,<substring>
+    # Example: INPUT=aes67,8f6326 will match a device name containing "8f6326".
+    input_env = os.environ.get('INPUT', 'usb') or 'usb'
+    parts = [p.strip() for p in input_env.split(',', 1)]
+    input_mode = (parts[0] or 'usb').lower()
+    iface_substr = (parts[1].lower() if len(parts) > 1 and parts[1] else None)
+
+    selected_dev = None
+    if input_mode == 'aes67':
+        if not aes67_inputs and not iface_substr:
+            # No AES67 inputs and no specific target -> fail fast
+            raise RuntimeError("No AES67 audio inputs found.")
+        if iface_substr:
+            # Loop until a matching AES67 input becomes available
+            while True:
+                current = list_network_pw_inputs()
+                sel = next(((i, d) for i, d in current if iface_substr in (d.get('name','').lower())), None)
+                if sel:
+                    input_sel = sel[0]
+                    selected_dev = sel[1]
+                    logging.info(f"Selected AES67 input by match '{iface_substr}': index={input_sel}")
+                    break
+                logging.info(f"Waiting for AES67 input matching '{iface_substr}'... retrying in 2s")
+                time.sleep(2)
+        else:
+            input_sel, selected_dev = aes67_inputs[0]
+            logging.info(f"Selected first AES67 input: index={input_sel}, device={selected_dev['name']}")
+    else:
+        if usb_inputs:
+            input_sel, selected_dev = usb_inputs[0]
+            logging.info(f"Selected first USB input: index={input_sel}, device={selected_dev['name']}")
+        else:
+            raise RuntimeError("No USB audio inputs found.")
+
+    TRANSPORT1 = 'serial:/dev/ttyAMA3,1000000,rtscts' # transport for raspberry pi gpio header
+    TRANSPORT2 = 'serial:/dev/ttyAMA4,1000000,rtscts' # transport for raspberry pi gpio header
+    # Capture at 48 kHz to avoid PipeWire resampler latency; encode LC3 at 24 kHz
+    CAPTURE_SRATE = 48000
+    LC3_SRATE = 24000
+    OCTETS_PER_FRAME=60
+
+    # Read uppercase-only settings from environment/.env
+    broadcast_name = os.environ.get('BROADCAST_NAME', 'Broadcast0')
+    program_info = os.environ.get('PROGRAM_INFO', 'Some Announcements')
+    # Note: 'LANGUATE' (typo) is intentionally used as requested, maps to config.language
+    language = os.environ.get('LANGUATE', 'deu')
+
+    # Determine capture channel count based on selected device (prefer up to 2)
+    try:
+        max_in = int((selected_dev or {}).get('max_input_channels', 1))
+    except Exception:
+        max_in = 1
+    channels = max(1, min(2, max_in))
+
+    config = auracast_config.AuracastConfigGroup(
+        bigs = [
+            auracast_config.AuracastBigConfig(
+                name=broadcast_name,
+                program_info=program_info,
+                language=language,
+                iso_que_len=1,
+                audio_source=f'device:{input_sel}',
+                input_format=f"int16le,{CAPTURE_SRATE},{channels}",
+                sampling_frequency=LC3_SRATE,
+                octets_per_frame=OCTETS_PER_FRAME,
+            ),
+            #auracast_config.AuracastBigConfigEng(),
+        ],
+        immediate_rendering=True,
+        presentation_delay_us=40000,
+        qos_config=auracast_config.AuracastQosHigh(),
+        auracast_sampling_rate_hz = LC3_SRATE,
+        octets_per_frame = OCTETS_PER_FRAME, # 32kbps@16kHz
+        transport=TRANSPORT1
+    )
+    #config.debug = True
+
+    multicast.run_async(
+        multicast.broadcast(
+            config,
+            config.bigs
+        )
+    )