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Multimodal

Speech-to-Text AI

Definition

Speech-to-text (STT) AI converts spoken audio into written text using models like Whisper and Deepgram, enabling transcription, voice interfaces, and accessibility features.

Why It Matters

Speech-to-text enables voice interfaces for applications, automated transcription of meetings and podcasts, accessibility for hearing-impaired users, and voice-driven AI agents. Modern STT has become accurate enough for production use across many languages and accents.

Key Solutions

API Services:

  • OpenAI Whisper API: High accuracy, 50+ languages
  • Deepgram: Real-time, enterprise features
  • AssemblyAI: Specialized features (speaker ID, sentiment)
  • Google Speech-to-Text: Google Cloud integration

Self-Hosted:

  • Whisper (local): Open-source, free, private
  • faster-whisper: Optimized Whisper implementation
  • Vosk: Lightweight offline recognition

Key Features to Consider

  • Accuracy: Word error rate for your content type
  • Latency: Real-time vs batch processing
  • Languages: Support for your target languages
  • Speaker Diarization: Who said what
  • Punctuation: Automatic formatting
  • Custom Vocabulary: Domain-specific terms