Merge pull request #931 from pipecat-ai/mb/fix-openai-realtime-

Fix truncation timing of OpenAIRealtimeBetaLLMService

CHANGELOG.md

@@ -14,6 +14,11 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Added `29-livekit-audio-chat.py`, as a new foundational examples for
   `LiveKitTransportLayer`.
 
+### Fixed
+
+- Fixed an issue where `OpenAIRealtimeBetaLLMService` audio chunks were hitting
+  an error when truncating audio content.
+
 ## [0.0.52] - 2024-12-24
 
 ### Added

src/pipecat/services/openai_realtime_beta/openai.py

@@ -152,17 +152,38 @@ class OpenAIRealtimeBetaLLMService(LLMService):
     async def _handle_bot_stopped_speaking(self):
         self._current_audio_response = None
 
+    def _calculate_audio_duration_ms(
+        self, total_bytes: int, sample_rate: int = 24000, bytes_per_sample: int = 2
+    ) -> int:
+        """Calculate audio duration in milliseconds based on PCM audio parameters."""
+        samples = total_bytes / bytes_per_sample
+        duration_seconds = samples / sample_rate
+        return int(duration_seconds * 1000)
+
     async def _truncate_current_audio_response(self):
+        """Truncates the current audio response at the appropriate duration.
+
+        Calculates the actual duration of the audio content and truncates at the shorter of
+        either the wall clock time or the actual audio duration to prevent invalid truncation
+        requests.
+        """
         # if the bot is still speaking, truncate the last message
         if self._current_audio_response:
             current = self._current_audio_response
             self._current_audio_response = None
+
+            # Calculate actual audio duration instead of using wall clock time
+            audio_duration_ms = self._calculate_audio_duration_ms(current.total_size)
+
+            # Use the shorter of wall clock time or actual audio duration
             elapsed_ms = int(time.time() * 1000 - current.start_time_ms)
+            truncate_ms = min(elapsed_ms, audio_duration_ms)
+
             await self.send_client_event(
                 events.ConversationItemTruncateEvent(
                     item_id=current.item_id,
                     content_index=current.content_index,
-                    audio_end_ms=elapsed_ms,
+                    audio_end_ms=truncate_ms,
                 )
             )