Add support for Piper TTS

src/pipecat/services/piper.py

@@ -0,0 +1,103 @@
+#
+# Copyright (c) 2024–2025, Daily
+#
+# SPDX-License-Identifier: BSD 2-Clause License
+#
+
+from typing import AsyncGenerator
+
+import aiohttp
+from loguru import logger
+
+from pipecat.frames.frames import (
+    ErrorFrame,
+    Frame,
+    TTSAudioRawFrame,
+    TTSStartedFrame,
+    TTSStoppedFrame,
+)
+from pipecat.services.ai_services import TTSService
+
+# This assumes a running TTS service running: https://github.com/rhasspy/piper/blob/master/src/python_run/README_http.md
+
+
+class PiperTTSService(TTSService):
+    """Piper TTS service implementation.
+
+    Provides integration with Piper's TTS server.
+    """
+
+    def __init__(
+        self,
+        *,
+        base_url: str,
+        aiohttp_session: aiohttp.ClientSession | None = None,
+        sample_rate: int = 24000,
+        **kwargs,
+    ):
+        """Initialize the PiperTTSService class instance.
+
+        Args:
+            base_url (str): Base URL of the Piper TTS server (should not end with a slash).
+            aiohttp_session (aiohttp.ClientSession, optional): Optional aiohttp session to use for requests. Defaults to None.
+            sample_rate (int, optional): Sample rate in Hz. Defaults to 24000.
+            **kwargs (dict): Additional keyword arguments.
+        """
+        super().__init__(sample_rate=sample_rate, **kwargs)
+        if not aiohttp_session:
+            aiohttp_session = aiohttp.ClientSession()
+
+        if base_url.endswith("/"):
+            logger.warning("Base URL ends with a slash, this is not allowed.")
+            base_url = base_url[:-1]
+
+        self._settings = {"base_url": base_url}
+        self.set_voice("voice_id")
+        self._aiohttp_session = aiohttp_session
+
+    def can_generate_metrics(self) -> bool:
+        return True
+
+    async def run_tts(self, text: str) -> AsyncGenerator[Frame, None]:
+        logger.debug(f"Generating TTS: [{text}]")
+
+        url = self._settings["base_url"] + "/?text=" + text.replace(".", "").replace("*", "")
+
+        await self.start_ttfb_metrics()
+
+        async with self._aiohttp_session.get(url) as r:
+            if r.status != 200:
+                text = await r.text()
+                logger.error(f"{self} error getting audio (status: {r.status}, error: {text})")
+                yield ErrorFrame(f"Error getting audio (status: {r.status}, error: {text})")
+                return
+
+            await self.start_tts_usage_metrics(text)
+
+            yield TTSStartedFrame()
+
+            buffer = bytearray()
+            async for chunk in r.content.iter_chunked(1024):
+                if len(chunk) > 0:
+                    await self.stop_ttfb_metrics()
+                    # Append new chunk to the buffer.
+                    buffer.extend(chunk)
+
+                    # Check if buffer has enough data for processing.
+                    while (
+                        len(buffer) >= 48000
+                    ):  # Assuming at least 0.5 seconds of audio data at 24000 Hz
+                        # Process the buffer up to a safe size for resampling.
+                        process_data = buffer[:48000]
+                        # Remove processed data from buffer.
+                        buffer = buffer[48000:]
+
+                        frame = TTSAudioRawFrame(process_data, self._sample_rate, 1)
+                        yield frame
+
+            # Process any remaining data in the buffer.
+            if len(buffer) > 0:
+                frame = TTSAudioRawFrame(buffer, self._sample_rate, 1)
+                yield frame
+
+            yield TTSStoppedFrame()