Text Chunking for TTS
Basic techniques for breaking text into chunks to reduce latency in Text-to-Speech applications.
Why Text Chunking Matters
Text chunking significantly reduces perceived latency in TTS applications by allowing audio playback to begin sooner. This is especially important for conversational AI and voice agents where responsiveness is critical.
Instead of waiting for the entire audio to be generated, chunking lets you:
- Begin audio playback much faster
- Create more responsive voice experiences
- Maintain natural-sounding speech
Basic Sentence Chunking
The simplest and most effective approach is to split text at sentence boundaries. This preserves natural speech patterns while enabling faster time-to-first-byte:
Processing Streaming Text with WebSockets
When working with streaming text (like from an LLM), you need to collect tokens until you have complete sentences. Here’s a simplified approach to process text chunks that arrive as paragraphs:
For complete details on implementing the TTS WebSocket connection, see our guide on Real-Time TTS with WebSockets.
Processing Chunked Text
After creating chunks, you have two main options for processing them:
Sequential Processing
Process each chunk in sequence, prioritizing the first chunk:
Setting Chunk Size
For most applications, sentences work well as chunks. If you need finer control:
- Voice assistants: Aim for 50-100 character chunks
- Call center bots: Use complete sentences (most natural)
- Long-form content: Larger chunks (200-400 characters) preserve intonation
Other Chunking Strategies
If you need more advanced chunking methods, search for these techniques:
- Clause-based chunking: Splits long sentences at commas and semicolons
- NLP-based chunking: Uses natural language processing to find semantic boundaries
- Adaptive chunking: Adjusts chunk size based on content complexity
- First-chunk optimization: Specially optimizes the first chunk for minimal latency
- SSML chunking: Handles Speech Synthesis Markup Language tags when chunking
For WebSocket implementation details to stream the chunked audio, see our guide on Real-Time TTS with WebSockets.