add immediate rendering flag

src/auracast/auracast_config.py

@@ -35,6 +35,10 @@ class AuracastGlobalConfig(BaseModel):
     presentation_delay_us: int = 40000
     # TODO:pydantic does not support bytes serialization - use .hex and np.fromhex()
     manufacturer_data: tuple[int, bytes] | tuple[None, None] = (None, None)
+    # LE Audio: Broadcast Audio Immediate Rendering (metadata type 0x09)
+    # When true, include a zero-length LTV with type 0x09 in the subgroup metadata
+    # so receivers may render earlier than the presentation delay for lower latency.
+    immediate_rendering: bool = False
 
 # "Audio input. "
 # "'device' -> use the host's default sound input device, "

src/auracast/multicast.py

@@ -235,6 +235,30 @@ async def init_broadcast(
     bap_sampling_freq = getattr(bap.SamplingFrequency, f"FREQ_{global_config.auracast_sampling_rate_hz}")
     bigs = {}
     for i, conf in enumerate(big_config):
+        metadata=le_audio.Metadata(
+            [
+                le_audio.Metadata.Entry(
+                    tag=le_audio.Metadata.Tag.LANGUAGE, data=conf.language.encode()
+                ),
+                le_audio.Metadata.Entry(
+                    tag=le_audio.Metadata.Tag.PROGRAM_INFO, data=conf.program_info.encode()
+                ),
+                le_audio.Metadata.Entry(
+                    tag=le_audio.Metadata.Tag.BROADCAST_NAME, data=conf.name.encode()
+                ),
+            ]
+            + (
+                [
+                    # Broadcast Audio Immediate Rendering flag (type 0x09), zero-length value
+                    le_audio.Metadata.Entry(tag = le_audio.Metadata.Tag.BROADCAST_AUDIO_IMMEDIATE_RENDERING_FLAG, data=b"")
+                ]
+                if global_config.immediate_rendering
+                else []
+            )
+        )
+        logging.info(
+            metadata.pretty_print("\n")
+        )
         bigs[f'big{i}'] = {}
         # Config advertising set
         bigs[f'big{i}']['basic_audio_announcement'] = bap.BasicAudioAnnouncement(
@@ -247,19 +271,7 @@ async def init_broadcast(
                         frame_duration=bap.FrameDuration.DURATION_10000_US,
                         octets_per_codec_frame=global_config.octets_per_frame,
                     ),
-                    metadata=le_audio.Metadata(
-                        [
-                            le_audio.Metadata.Entry(
-                                tag=le_audio.Metadata.Tag.LANGUAGE, data=conf.language.encode()
-                            ),
-                            le_audio.Metadata.Entry(
-                                tag=le_audio.Metadata.Tag.PROGRAM_INFO, data=conf.program_info.encode()
-                            ),
-                            le_audio.Metadata.Entry(
-                            tag=le_audio.Metadata.Tag.BROADCAST_NAME, data=conf.name.encode()
-                            ),
-                        ]
-                    ),
+                    metadata=metadata,
                     bis=[
                         bap.BasicAudioAnnouncement.BIS(
                             index=1,

src/auracast/multicast_script.py

@@ -1,13 +1,10 @@
 import logging
 import os
-import asyncio
-import aioconsole
 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
@@ -25,8 +22,9 @@ if __name__ == "__main__":
     os.environ.setdefault("AURACAST_SD_BLOCKSIZE", "32")
     # Accepts 'low'/'high'/'default' or seconds (float). Our shim parses number strings to float.
     os.environ.setdefault("AURACAST_SD_LATENCY", "0.0015")
-    print("USB pw inputs:")
+    logging.info("USB pw inputs:")
     usb_inputs = list_usb_pw_inputs()
+    logging.info("AEs67 pw inputs:")
     aes67_inputs = list_network_pw_inputs()
     for i, d in usb_inputs:
         logging.info(f"{i}: {d['name']}  in={d['max_input_channels']}")
@@ -62,17 +60,13 @@ if __name__ == "__main__":
                 octets_per_frame=OCTETS_PER_FRAME,
             ),
             #auracast_config.AuracastBigConfigEng(),
-
-        ]
+        ],
+        immediate_rendering=True,
+        qos_config=auracast_config.AuracastQosHigh(),
+        auracast_sampling_rate_hz = LC3_SRATE,
+        octets_per_frame = OCTETS_PER_FRAME, # 32kbps@16kHz
+        transport=TRANSPORT1
     )
-
-    config.qos_config=auracast_config.AuracastQosHigh()
-    config.transport=TRANSPORT1
-
-    # TODO: encrypted streams are not working
-
-    config.auracast_sampling_rate_hz = LC3_SRATE
-    config.octets_per_frame = OCTETS_PER_FRAME # 32kbps@16kHz
     #config.debug = True
 
     multicast.run_async(

src/scripts/list_pw_nodes.py

@@ -14,10 +14,6 @@ print("\nOnly PulseAudio devices:")
 for i, d in devices_by_backend("PulseAudio"):
     print(f"{i}: {d['name']}  in={d['max_input_channels']} out={d['max_output_channels']}")
 
-# Example: only PulseAudio devices on Linux
-# print("\nOnly JACK devices:")
-# for i, d in devices_by_backend("JACK"):
-#     print(f"{i}: {d['name']}  in={d['max_input_channels']} out={d['max_output_channels']}")
 
 print("Network pw inputs:")
 for i, d in list_network_pw_inputs():