Top Open-Source Speech-to-Text Models

Apr 9, 2025

Gladia - Top 5 Open-Source Speech-to-Text Models for Enterprises

Introduction

  • Open-source STT Models: Democratize access to ASR capabilities.
  • Benefits: Customizable, cost-effective solutions without proprietary constraints; suitable for specific use cases.
  • Purpose: Identify the best models for speech-powered apps.

Speech-to-Text Models

  • Functionality: Transcribe spoken words to digital text, facilitating analysis and manipulation of audio data.
  • Applications: Telecommunications, healthcare, education, customer service, and entertainment.
  • Architecture: Encoder-decoder; enables near-human-level transcription.
  • Use: Voice-controlled applications, virtual assistants, smart devices.
  • Selection Criteria: Accuracy, performance, flexibility, customizability, community support.

Featured Models

1. Whisper ASR

  • Developer: OpenAI
  • Data: 680,000 hours of multilingual data.
  • Strengths:
    • High accuracy; handles accents, noise.
    • Transcribes and translates multiple languages.
    • Performs multiple tasks with a single model.
  • Limitations:
    • Input limitations; lacks features like speaker diarization.
    • Unsuitable for enterprise scale without optimization.

2. DeepSpeech

  • Developer: Mozilla
  • Method: Deep neural network, N-gram language model.
  • Strengths:
    • Multilingual, flexible, retrainable.
  • Limitations:
    • 10-second recording limit; not suitable for long transcriptions.

3. Wav2vec

  • Developer: Meta
  • Method: Self-supervised model with unlabeled data.
  • Strengths:
    • Reduces need for labeled data.
    • Unsurpassed performance with less data.
  • Applications: Processing audio from underrepresented languages.

4. Kaldi

  • Language: C++
  • Purpose: Toolkit for building speech recognition systems.
  • Strengths:
    • Generic and modular, runs on various platforms.
    • Not an out-of-the-box system; requires setup.

5. SpeechBrain

  • Method: PyTorch toolkit for conversational AI.
  • Strengths:
    • All-in-one toolkit for ASR, speech synthesis, etc.
    • Strong academic backing, large community support.
  • Limitations:
    • Variable quality of models; extensive testing needed.

Practical Considerations

  • Deployment Costs: Hardware, expertise, scaling limitations.
  • Feature Set: Open-source models may lack features, require optimization.
  • Alternatives: Specialized APIs offer pre-built features and expert advice.

Final Remarks

  • Model Selection: Consider accuracy, flexibility, and community support.
  • Usage: Some models require tailored training; others offer modular pieces for custom setups.
  • Goal: Find the model best suited for specific enterprise needs.

Resources

About Gladia

  • Offering: Optimized Whisper API for professional use; features include speaker diarization, word-level timestamps.