Merge pull request #1889 from pipecat-ai/mb/add-dtmf-aggregator

Add DTMFAggregator
2025-05-29 17:13:28 -04:00
parent 36b731be73 4d2a02f318
commit a471f49b61
3 changed files with 377 additions and 0 deletions
--- a/src/pipecat/processors/aggregators/dtmf_aggregator.py
+++ b/src/pipecat/processors/aggregators/dtmf_aggregator.py
@@ -0,0 +1,143 @@
+#
+# Copyright (c) 2024–2025, Daily
+#
+# SPDX-License-Identifier: BSD 2-Clause License
+#
+
+import asyncio
+from typing import Optional
+
+from pipecat.frames.frames import (
+    BotInterruptionFrame,
+    CancelFrame,
+    EndFrame,
+    Frame,
+    InputDTMFFrame,
+    KeypadEntry,
+    StartFrame,
+    TranscriptionFrame,
+)
+from pipecat.processors.frame_processor import FrameDirection, FrameProcessor
+from pipecat.utils.time import time_now_iso8601
+
+
+class DTMFAggregator(FrameProcessor):
+    """Aggregates DTMF frames into meaningful sequences for LLM processing.
+
+    The aggregator accumulates digits from InputDTMFFrame instances and flushes
+    when:
+    - Timeout occurs (configurable idle period)
+    - Termination digit is received (default: '#')
+    - EndFrame or CancelFrame is received
+
+    Emits TranscriptionFrame for compatibility with existing LLM context aggregators.
+
+    Args:
+        timeout: Idle timeout in seconds before flushing
+        termination_digit: Digit that triggers immediate flush
+        prefix: Prefix added to DTMF sequence in transcription
+    """
+
+    def __init__(
+        self,
+        timeout: float = 2.0,
+        termination_digit: KeypadEntry = KeypadEntry.POUND,
+        prefix: str = "DTMF: ",
+        **kwargs,
+    ):
+        super().__init__(**kwargs)
+        self._aggregation = ""
+        self._idle_timeout = timeout
+        self._termination_digit = termination_digit
+        self._prefix = prefix
+
+        self._digit_event = asyncio.Event()
+        self._aggregation_task: Optional[asyncio.Task] = None
+
+    async def process_frame(self, frame: Frame, direction: FrameDirection) -> None:
+        await super().process_frame(frame, direction)
+
+        if isinstance(frame, StartFrame):
+            self._create_aggregation_task()
+            await self.push_frame(frame, direction)
+        elif isinstance(frame, (EndFrame, CancelFrame)):
+            if self._aggregation:
+                await self._flush_aggregation()
+            await self._stop_aggregation_task()
+            await self.push_frame(frame, direction)
+        elif isinstance(frame, InputDTMFFrame):
+            # Push the DTMF frame downstream first
+            await self.push_frame(frame, direction)
+            # Then handle it in order for the TranscriptionFrame to be emitted
+            # after the InputDTMFFrame
+            await self._handle_dtmf_frame(frame)
+        else:
+            await self.push_frame(frame, direction)
+
+    async def _handle_dtmf_frame(self, frame: InputDTMFFrame):
+        """Handle DTMF input frame."""
+        is_first_digit = not self._aggregation
+
+        digit_value = frame.button.value
+        self._aggregation += digit_value
+
+        # For first digit, schedule interruption in separate task
+        if is_first_digit:
+            asyncio.create_task(self._send_interruption_task())
+
+        # Check for immediate flush conditions
+        if frame.button == self._termination_digit:
+            await self._flush_aggregation()
+        else:
+            # Signal digit received for timeout handling
+            self._digit_event.set()
+
+    async def _send_interruption_task(self):
+        """Send interruption frame safely in a separate task."""
+        try:
+            # Send the interruption frame
+            await self.push_frame(BotInterruptionFrame(), FrameDirection.UPSTREAM)
+        except Exception as e:
+            # Log error but don't propagate
+            print(f"Error sending interruption: {e}")
+
+    def _create_aggregation_task(self) -> None:
+        """Creates the aggregation task if it hasn't been created yet."""
+        if not self._aggregation_task:
+            self._aggregation_task = self.create_task(self._aggregation_task_handler())
+
+    async def _stop_aggregation_task(self) -> None:
+        """Stops the aggregation task."""
+        if self._aggregation_task:
+            await self.cancel_task(self._aggregation_task)
+            self._aggregation_task = None
+
+    async def _aggregation_task_handler(self):
+        """Background task that handles timeout-based flushing."""
+        while True:
+            try:
+                await asyncio.wait_for(self._digit_event.wait(), timeout=self._idle_timeout)
+                self._digit_event.clear()
+            except asyncio.TimeoutError:
+                if self._aggregation:
+                    await self._flush_aggregation()
+
+    async def _flush_aggregation(self):
+        """Flush the current aggregation as a TranscriptionFrame."""
+        if not self._aggregation:
+            return
+
+        sequence = self._aggregation
+        transcription_text = f"{self._prefix}{sequence}"
+
+        transcription_frame = TranscriptionFrame(
+            text=transcription_text, user_id="", timestamp=time_now_iso8601()
+        )
+        await self.push_frame(transcription_frame)
+
+        self._aggregation = ""
+
+    async def cleanup(self) -> None:
+        """Clean up resources."""
+        await super().cleanup()
+        await self._stop_aggregation_task()