Formatting adjusted and the encoding selection moved from TelnyFrameSerilaizer to websocket_endpoint function in server.py

examples/telnyx-chatbot/README.md

@@ -76,7 +76,7 @@ This project is a FastAPI-based chatbot that integrates with Telnyx to handle We
      ```
    - In `templates/streams.xml`, replace `<your server url>` with your ngrok URL (without `https://`)
    - The final URL should look like: `wss://abc123.ngrok.io/ws`
-   - The encoding (`bidirectionalCodec`) should be `PCMU` or `PCMA` depending on your needs. Based on selected encoding, set the outbound_encoding in the `TelnyxFrameSerializer` in `src/pipecat/serializers/telnyx.py`
+   - The encoding (`bidirectionalCodec`) should be `PCMU` or `PCMA` depending on your needs. Based on selected encoding, set the outbound_encoding in `server.py` when the bot is initialized.
    - The inbound encoding can be controlled from the application configuration for inbound calls and dial/transfer commands for outbound calls.
 
 ## Running the Application

examples/telnyx-chatbot/bot.py

@@ -34,7 +34,7 @@ logger.remove(0)
 logger.add(sys.stderr, level="DEBUG")
 
 
-async def run_bot(websocket_client, stream_id, encoding):
+async def run_bot(websocket_client, stream_id, outbound_encoding, inbound_encoding):
     transport = FastAPIWebsocketTransport(
         websocket=websocket_client,
         params=FastAPIWebsocketParams(
@@ -43,7 +43,7 @@ async def run_bot(websocket_client, stream_id, encoding):
             vad_enabled=True,
             vad_analyzer=SileroVADAnalyzer(),
             vad_audio_passthrough=True,
-            serializer=TelnyxFrameSerializer(stream_id, encoding),
+            serializer=TelnyxFrameSerializer(stream_id, outbound_encoding, inbound_encoding),
         ),
     )
 
@@ -55,9 +55,7 @@ async def run_bot(websocket_client, stream_id, encoding):
         api_key=os.getenv("ELEVENLABS_API_KEY"),
         voice_id="CwhRBWXzGAHq8TQ4Fs17",
         output_format="pcm_24000",
-        params=ElevenLabsTTSService.InputParams(
+        params=ElevenLabsTTSService.InputParams(language=Language.EN),
-            language=Language.EN
-        )
     )
 
     messages = [

examples/telnyx-chatbot/server.py

@@ -16,13 +16,11 @@ app.add_middleware(
     allow_headers=["*"],
 )
 
-
 @app.post("/")
 async def start_call():
     print("POST TeXML")
     return HTMLResponse(content=open("templates/streams.xml").read(), media_type="application/xml")
 
-
 @app.websocket("/ws")
 async def websocket_endpoint(websocket: WebSocket):
     await websocket.accept()
@@ -31,10 +29,9 @@ async def websocket_endpoint(websocket: WebSocket):
     call_data = json.loads(await start_data.__anext__())
     print(call_data, flush=True)
     stream_id = call_data["stream_id"]
-    encoding = call_data["start"]["media_format"]["encoding"]
+    outbound_encoding = call_data["start"]["media_format"]["encoding"]
     print("WebSocket connection accepted")
-    await run_bot(websocket, stream_id, encoding)
+    await run_bot(websocket, stream_id, outbound_encoding, "PCMU")
-
 
 if __name__ == "__main__":
     uvicorn.run(app, host="0.0.0.0", port=8765)

src/pipecat/audio/utils.py

@@ -84,6 +84,7 @@ def ulaw_to_pcm(ulaw_bytes: bytes, in_sample_rate: int, out_sample_rate: int):
     
     return out_pcm_bytes
 
+
 def pcm_to_ulaw(pcm_bytes: bytes, in_sample_rate: int, out_sample_rate: int):
     # Resample
     in_pcm_bytes = resample_audio(pcm_bytes, in_sample_rate, out_sample_rate)
@@ -93,8 +94,8 @@ def pcm_to_ulaw(pcm_bytes: bytes, in_sample_rate: int, out_sample_rate: int):
 
     return ulaw_bytes
 
-def alaw_to_pcm(alaw_bytes: bytes, in_sample_rate: int, out_sample_rate: int) -> bytes:
+
-        
+def alaw_to_pcm(alaw_bytes: bytes, in_sample_rate: int, out_sample_rate: int) -> bytes:     
     # Convert a-law to PCM
     in_pcm_bytes = audioop.alaw2lin(alaw_bytes, 2)
 
@@ -103,6 +104,7 @@ def alaw_to_pcm(alaw_bytes: bytes, in_sample_rate: int, out_sample_rate: int) ->
     
     return out_pcm_bytes
 
+
 def pcm_to_alaw(pcm_bytes: bytes, in_sample_rate: int, out_sample_rate: int):
     # Resample
     in_pcm_bytes = resample_audio(pcm_bytes, in_sample_rate, out_sample_rate)
@@ -110,4 +112,4 @@ def pcm_to_alaw(pcm_bytes: bytes, in_sample_rate: int, out_sample_rate: int):
     # Convert PCM to μ-law
     alaw_bytes = audioop.lin2alaw(in_pcm_bytes, 2)
 
-    return alaw_bytes
+    return alaw_bytes

src/pipecat/serializers/telnyx.py

@@ -28,9 +28,10 @@ class TelnyxFrameSerializer(FrameSerializer):
         inbound_encoding: str = "PCMU"
         outbound_encoding: str = "PCMU"
 
-    def __init__(self, stream_id: str, encoding: str, params: InputParams = InputParams()):
+    def __init__(self, stream_id: str, outbound_encoding: str, inbound_encoding: str, params: InputParams = InputParams()):
         self._stream_id = stream_id
-        params.inbound_encoding = encoding
+        params.outbound_encoding = outbound_encoding
+        params.inbound_encoding = inbound_encoding  
         self._params = params
 
     @property
@@ -41,10 +42,14 @@ class TelnyxFrameSerializer(FrameSerializer):
         if isinstance(frame, AudioRawFrame):
             data = frame.audio
             
-            if self._params.outbound_encoding == "PCMU":
+            if self._params.inbound_encoding == "PCMU":
-                serialized_data = pcm_to_ulaw(data, frame.sample_rate, self._params.telnyx_sample_rate)
+                serialized_data = pcm_to_ulaw(
-            elif self._params.outbound_encoding == "PCMA":
+                    data, frame.sample_rate, self._params.telnyx_sample_rate
-                serialized_data = pcm_to_alaw(data, frame.sample_rate, self._params.telnyx_sample_rate)
+                    )
+            elif self._params.inbound_encoding == "PCMA":
+                serialized_data = pcm_to_alaw(
+                    data, frame.sample_rate, self._params.telnyx_sample_rate
+                    )
             else:
                 raise ValueError(f"Unsupported encoding: {self._params.encoding}")
             
@@ -67,11 +72,11 @@ class TelnyxFrameSerializer(FrameSerializer):
             payload_base64 = message["media"]["payload"]
             payload = base64.b64decode(payload_base64)
 
-            if self._params.inbound_encoding == "PCMU":
+            if self._params.outbound_encoding == "PCMU":
                 deserialized_data = ulaw_to_pcm(
                     payload, self._params.telnyx_sample_rate, self._params.sample_rate
                 )
-            elif self._params.inbound_encoding == "PCMA":
+            elif self._params.outbound_encoding == "PCMA":
                 deserialized_data = alaw_to_pcm(
                     payload, self._params.telnyx_sample_rate, self._params.sample_rate
                 )