API Documentation

Explore Velma-2 voice models - Deepfake Detection, Transcription, Emotion Detection, and more.

Velma-2 Models

Velma-2's synthetic voice detection models achieve state-of-the-art performance detecting speech deepfakes on single-speaker audio.

Batch English Fast Batch Multilingual Streaming Multilingual
Description High-throughput English batch processing with >200x real-time speed Multilingual batch transcription in 70+ languages with full feature set Real-time streaming transcription in 70+ languages via WebSocket
Endpoint /api/velma-2-stt-batch-english-vfast /api/velma-2-stt-batch /api/velma-2-stt-streaming
Type Batch Batch Streaming
API REST API REST API WebSocket
Accepted Files AAC, AIFF, FLAC, MOV, MP3, MP4, OGG, Opus, WAV, WebM AAC, AIFF, FLAC, MOV, MP3, MP4, OGG, Opus, WAV, WebM AAC, AIFF, FLAC, MOV, MP3, MP4, OGG, Opus, WAV, WebM
Pricing $0.025 / hour $0.03 / hour $0.06 / hour
Built-in Features
Transcription
Auto Capitalization
Auto Punctuation
Language English 70+ languages 70+ languages
Real-Time
Optional Features
Speaker Diarization
Emotion Detection
Accent Identification
PII/PHI Tagging
Deepfake Batch Deepfake Streaming
Description Speech deepfake prediction for audio files with a single speaker Real-time speech deepfake detection for streaming audio with a single speaker
Accuracy 98.9% average — #1 on Speech DF Arena 98.9% average — #1 on Speech DF Arena
Endpoint /api/velma-2-synthetic-voice-detection-batch /api/velma-2-synthetic-voice-detection-streaming
Type Deepfake Batch Deepfake Streaming
API REST API WebSocket
Accepted Files AAC, AIFF, FLAC, MOV, MP3, MP4, OGG, Opus, WAV, WebM Raw 16kHz mono PCM (int16 LE)
Pricing $0.25 / hour $0.25 / hour
Built-in Features
Per-Window Prediction
Confidence Scoring
Silence Detection
Flexible Chunk Size
Real-Time
First Prediction After full file upload At 500ms of audio

Authentication & Rate Limits

Authentication

REST endpoints require an API key via the X-API-Key header. The WebSocket endpoint uses an api_key query parameter.

REST:      X-API-Key: your_api_key_here
WebSocket: wss://...?api_key=your_api_key_here
Rate Limits & Billing
  • Per-model concurrency and monthly usage quotas
  • Credit-based billing with free tier included
  • Usage tracked in real time via the Usage Dashboard
Models
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Select a model from the sidebar to view its documentation, API spec, and quickstart guide.

Example Projects Coming Soon

We're preparing example projects to help you get started with the Velma-2 API. Check back soon for ready-to-use code samples and integration guides.

API Specs
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