Quick start

This page goes from nothing to a transcript. The same shape applies to every other Modulate model: one key, one request, one response.

Before starting

Get an API key

Create a free account, then create a key from the API Keys tab in the dashboard.

Store the key

Set it as an environment variable rather than hard-coding it.

export MODULATE_API_KEY=your_api_key_here

Get a sample audio file

Any speech clip of 5 to 30 seconds works. The examples below assume audio.mp3 in the working directory.

The curl example needs nothing else. The Python example needs requests:

pip install requests

Make the first call

curl -X POST https://platform.modulate.ai/api/velma-2-stt-batch \
  -H "X-API-Key: $MODULATE_API_KEY" \
  -F "upload_file=@audio.mp3"

import os, requests

response = requests.post(
    "https://platform.modulate.ai/api/velma-2-stt-batch",
    headers={"X-API-Key": os.environ["MODULATE_API_KEY"]},
    files={"upload_file": open("audio.mp3", "rb")},
)
response.raise_for_status()
print(response.json()["text"])

import fs from "fs";
import FormData from "form-data";

const form = new FormData();
form.append("upload_file", fs.createReadStream("audio.mp3"), { filename: "audio.mp3" });

const response = await fetch("https://platform.modulate.ai/api/velma-2-stt-batch", {
  method: "POST",
  headers: { "X-API-Key": process.env.MODULATE_API_KEY, ...form.getHeaders() },
  body: form,
});

const result = await response.json();
console.log(result.text);

The response is application/json.

Response

{
  "text": "Hello everyone. Welcome to the meeting. We'll be discussing results today.",
  "duration_ms": 8400,
  "utterances": [
    {
      "utterance_uuid": "a1b2c3d4-e5f6-7890-abcd-ef1234567890",
      "text": "Hello everyone. Welcome to the meeting.",
      "start_ms": 0,
      "duration_ms": 4200,
      "speaker": 1,
      "language": "en",
      "emotion": null,
      "accent": null,
      "deepfake_score": null
    },
    {
      "utterance_uuid": "b2c3d4e5-f6a7-8901-bcde-f23456789012",
      "text": "We'll be discussing results today.",
      "start_ms": 4200,
      "duration_ms": 4200,
      "speaker": 1,
      "language": "en",
      "emotion": null,
      "accent": null,
      "deepfake_score": null
    }
  ]
}

text is the full transcript. utterances breaks it into speaker turns with millisecond timing and a language detected per utterance. emotion, accent, and deepfake_score are null until those signals are enabled. See Transcription. Response formats differ across the API. Most endpoints return JSON, PII/PHI Redaction batch returns multipart/form-data, and the streaming endpoints return sequences of JSON messages, some interleaved with binary audio frames. Each capability page states the format for its endpoints.

Go deeper by capability

Each page states what the endpoint returns, what can be configured, the accepted audio formats, and a runnable call for every endpoint in that family.

Velma Triage

Behaviors, topics, sentiment, and a summary across a whole conversation.

Transcription

Multilingual, English Fast, and Multilingual Fast. Batch and streaming.

Deepfake Detection

Per-frame synthetic-voice verdicts on files or live audio.

PII/PHI Redaction

A redacted transcript plus audio with the sensitive ranges silenced.

Emotion Detection

A whole-file emotion label plus a per-window time series.

Accent Detection

A whole-file accent label plus a per-window time series.

Music & Speech Detection

Frame-level music and speech probabilities.

AI Music Detection

Whether a track contains AI-generated vocals or instrumentals.

Language Detection

The spoken language of a clip, with a confidence score.

Which API should I use? works from the output backwards to the endpoint that produces it.

Get started

By capability

Guides

Before starting

Make the first call

Go deeper by capability

Velma Triage

Transcription

Deepfake Detection

PII/PHI Redaction

Emotion Detection

Accent Detection

Music & Speech Detection

AI Music Detection

Language Detection

​Before starting

​Make the first call

​Go deeper by capability

Velma Triage

Transcription

Deepfake Detection

PII/PHI Redaction

Emotion Detection

Accent Detection

Music & Speech Detection

AI Music Detection

Language Detection

Before starting

Make the first call

Go deeper by capability