Gemini API Text-to-Speech Example

A simple Python example demonstrating how to use Google's Gemini API for text-to-speech generation, based on the official documentation.

Features

• 🎤 Single-speaker TTS: Convert text to speech with 30 different voice options
• 👥 Multi-speaker TTS: Create conversations between 2 people with different voices
• 🎨 Style Control: Use natural language to control tone, pace, and emotion
• 📁 WAV Output: Save generated speech as high-quality WAV files
• 🛡️ Error Handling: Robust error handling and user feedback
• 🎭 Real-world Examples: Podcast, customer service, education, and interview scenarios

Prerequisites

1. Google AI API Key: Get your API key from Google AI Studio
2. Python 3.7+: Make sure you have Python installed

Installation

1. Clone or download this repository

2. Install dependencies:

   pip install -r requirements.txt

3. Set up your API key using one of these methods:

   Method 1: Using .env file (Recommended)

   # Create a .env file in the project root
   echo "GEMINI_API_KEY=your_api_key_here" > .env

   Method 2: Environment variable

   # On Windows
   set GEMINI_API_KEY=your_api_key_here
   
   # On macOS/Linux
   export GEMINI_API_KEY=your_api_key_here

Usage

Basic Usage

from gemini_tts_example import text_to_speech_simple

# Simple text-to-speech
text_to_speech_simple(
    text="Hello, this is a test of Gemini TTS!",
    voice_name="Kore",
    output_file="my_speech.wav"
)

With Style Control

from gemini_tts_example import text_to_speech_with_style

# Text-to-speech with emotional style
text_to_speech_with_style(
    text="Welcome to the future of AI!",
    style_instruction="Say excitedly and enthusiastically:",
    voice_name="Puck",
    output_file="excited_speech.wav"
)

Multi-Speaker Conversations

from gemini_tts_example import text_to_speech_multi_speaker

# Create a conversation between two people
dialogue = """Alice: Hey Bob! Did you hear about the new AI features?

Bob: Yes! The text-to-speech quality is incredible!

Alice: I know, right? It sounds so natural and expressive."""

speakers = [
    {"name": "Alice", "voice": "Leda"},   # Youthful
    {"name": "Bob", "voice": "Puck"}     # Upbeat  
]

text_to_speech_multi_speaker(dialogue, speakers, "conversation.wav")

Run Examples

# Run all examples (single and multi-speaker)
python gemini_tts_example.py

# Run only multi-speaker demos
python multi_speaker_demo.py

On Windows you can launch these examples from the interactive run_demos.bat script.

Single-speaker examples:

• basic_example.wav - Basic TTS
• cheerful_example.wav - Cheerful style
• mysterious_example.wav - Mysterious whisper

Multi-speaker examples:

• tech_discussion.wav - Tech podcast conversation
• casual_chat.wav - Friends chatting
• styled_conversation.wav - Emotional dialogue

Multi-speaker demo scenarios:

• podcast_demo.wav - Professional podcast
• customer_service_demo.wav - Support call
• teacher_student_demo.wav - Educational interaction
• interview_demo.wav - Job interview scenario

Available Voices

The API supports 30 different voices with various characteristics:

Voice	Style	Voice	Style
Kore	Firm	Puck	Upbeat
Zephyr	Bright	Charon	Informative
Enceladus	Breathy	Fenrir	Excitable
Aoede	Breezy	Leda	Youthful

See full voice list in documentation

Supported Models

• gemini-2.5-flash-preview-tts - Fast, efficient TTS
• gemini-2.5-pro-preview-tts - High-quality TTS

Supported Languages

The API automatically detects input language and supports 24 languages including:

• English (US, India)
• Spanish, French, German
• Japanese, Korean, Chinese
• Hindi, Arabic, Russian
• And many more...

Style Control Examples

You can control speech style using natural language:

# Different emotional styles
"Say cheerfully: Have a wonderful day!"
"Say in a spooky whisper: Something wicked this way comes"
"Say tiredly and bored: What's on the agenda today?"
"Say excitedly: You're never going to guess what happened!"

Technical Details

• Context Window: 32k tokens
• Audio Format: 24kHz, 16-bit PCM, Mono WAV
• API: Google Gemini API with native TTS capabilities

Troubleshooting

1. API Key Error: Make sure GEMINI_API_KEY environment variable is set
2. Import Error: Install dependencies with pip install -r requirements.txt
3. Audio Issues: Generated files are in WAV format - use any audio player

References

• Gemini API Speech Generation Documentation
• Google AI Studio
• Gemini API Cookbook

License

This example is provided for educational purposes. Please refer to Google's terms of service for API usage.