From 2ee481d5411c90e947f5d064b149ced64f160021 Mon Sep 17 00:00:00 2001
From: Manish Kumar <manishkjs@google.com>
Date: Sat, 30 Aug 2025 22:59:10 +0530
Subject: [PATCH] feat: add voice cloning and speaking rate to GoogleTTSService

---
 src/pipecat/services/google/tts.py | 20 +++++++++++++++++---
 1 file changed, 17 insertions(+), 3 deletions(-)

diff --git a/src/pipecat/services/google/tts.py b/src/pipecat/services/google/tts.py
index 6fb99a728..676896cc7 100644
--- a/src/pipecat/services/google/tts.py
+++ b/src/pipecat/services/google/tts.py
@@ -500,9 +500,11 @@ class GoogleTTSService(TTSService):
 
         Parameters:
             language: Language for synthesis. Defaults to English.
+            speaking_rate: The speaking rate, in the range [0.25, 4.0].
         """
 
         language: Optional[Language] = Language.EN
+        speaking_rate: Optional[float] = None
 
     def __init__(
         self,
@@ -510,6 +512,7 @@ class GoogleTTSService(TTSService):
         credentials: Optional[str] = None,
         credentials_path: Optional[str] = None,
         voice_id: str = "en-US-Chirp3-HD-Charon",
+        voice_cloning_key: Optional[str] = None,
         sample_rate: Optional[int] = None,
         params: InputParams = InputParams(),
         **kwargs,
@@ -532,8 +535,10 @@ class GoogleTTSService(TTSService):
             "language": self.language_to_service_language(params.language)
             if params.language
             else "en-US",
+            "speaking_rate": params.speaking_rate,
         }
         self.set_voice(voice_id)
+        self._voice_cloning_key = voice_cloning_key
         self._client: texttospeech_v1.TextToSpeechAsyncClient = self._create_client(
             credentials, credentials_path
         )
@@ -600,15 +605,24 @@ class GoogleTTSService(TTSService):
         try:
             await self.start_ttfb_metrics()
 
-            voice = texttospeech_v1.VoiceSelectionParams(
-                language_code=self._settings["language"], name=self._voice_id
-            )
+            if self._voice_cloning_key:
+                voice_clone_params = texttospeech_v1.VoiceCloneParams(
+                    voice_cloning_key=self._voice_cloning_key
+                )
+                voice = texttospeech_v1.VoiceSelectionParams(
+                    language_code=self._settings["language"], voice_clone=voice_clone_params
+                )
+            else:
+                voice = texttospeech_v1.VoiceSelectionParams(
+                    language_code=self._settings["language"], name=self._voice_id
+                )
 
             streaming_config = texttospeech_v1.StreamingSynthesizeConfig(
                 voice=voice,
                 streaming_audio_config=texttospeech_v1.StreamingAudioConfig(
                     audio_encoding=texttospeech_v1.AudioEncoding.PCM,
                     sample_rate_hertz=self.sample_rate,
+                    speaking_rate=self._settings["speaking_rate"],
                 ),
             )
             config_request = texttospeech_v1.StreamingSynthesizeRequest(