feat: add ElevenLabsTTS

Author: maciejmajek

src/rai_tts/rai_tts/models/__init__.py

@@ -13,6 +13,7 @@
 # limitations under the License.
 
 from .base import TTSModel, TTSModelError
+from .elevenlabs_tts import ElevenLabsTTS
 from .open_tts import OpenTTS
 
-__all__ = ["OpenTTS", "TTSModel", "TTSModelError"]
+__all__ = ["ElevenLabsTTS", "OpenTTS", "TTSModel", "TTSModelError"]

src/rai_tts/rai_tts/models/elevenlabs_tts.py

@@ -0,0 +1,112 @@
+# Copyright (C) 2024 Robotec.AI
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import os
+from io import BytesIO
+from typing import Tuple
+
+from elevenlabs.client import ElevenLabs
+from elevenlabs.types import Voice
+from elevenlabs.types.voice_settings import VoiceSettings
+from pydub import AudioSegment
+
+from rai_tts.models import TTSModel, TTSModelError
+
+
+class ElevenLabsTTS(TTSModel):
+    """
+    A text-to-speech (TTS) model interface for ElevenLabs.
+
+    Parameters
+    ----------
+    voice : str, optional
+        The voice model to use.
+    base_url : str, optional
+        The API endpoint for the ElevenLabs API, by default None.
+    """
+
+    def __init__(
+        self,
+        voice: str,
+        base_url: str | None = None,
+    ):
+        api_key = os.getenv(key="ELEVENLABS_API_KEY")
+        if api_key is None:
+            raise TTSModelError("ELEVENLABS_API_KEY environment variable is not set.")
+
+        self.client = ElevenLabs(base_url=base_url, api_key=api_key)
+        self.voice_settings = VoiceSettings(
+            stability=0.7,
+            similarity_boost=0.5,
+        )
+
+        voices = self.client.voices.get_all().voices
+        voice_id = next((v.voice_id for v in voices if v.name == voice), None)
+        if voice_id is None:
+            raise TTSModelError(f"Voice {voice} not found")
+        self.voice = Voice(voice_id=voice_id, settings=self.voice_settings)
+
+    def get_speech(self, text: str) -> AudioSegment:
+        """
+        Converts text into speech using the ElevenLabs API.
+
+        Parameters
+        ----------
+        text : str
+            The input text to be converted into speech.
+
+        Returns
+        -------
+        AudioSegment
+            The generated speech as an `AudioSegment` object.
+
+        Raises
+        ------
+        TTSModelError
+            If there is an issue with the request or the ElevenLabs API is unreachable.
+            If the response does not contain valid audio data.
+        """
+        try:
+            response = self.client.generate(
+                text=text,
+                voice=self.voice,
+                optimize_streaming_latency=4,
+            )
+            audio_data = b"".join(response)
+        except Exception as e:
+            raise TTSModelError(f"Error occurred while fetching audio: {e}") from e
+
+        # Load audio into memory (ElevenLabs returns MP3)
+        audio_segment = AudioSegment.from_mp3(BytesIO(audio_data))
+        return audio_segment
+
+    def get_tts_params(self) -> Tuple[int, int]:
+        """
+        Returns TTS sampling rate and channels.
+
+        The information is retrieved by running a sample transcription request, to ensure that the information will be accurate for generation.
+
+        Returns
+        -------
+        Tuple[int, int]
+            sample rate, channels
+
+        Raises
+        ------
+        TTSModelError
+            If there is an issue with the request or the ElevenLabs API is unreachable.
+            If the response does not contain valid audio data.
+        """
+        data = self.get_speech("A")
+        return data.frame_rate, 1