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Speech Threshold

For the complete documentation index, see llms.txt

cURL quickstart — Speech Threshold

# Submit transcription with speech_threshold (0 to 1)
curl  \
  --header "Authorization: YOUR_API_KEY" \
  --header "Content-Type: application/json" \
  --data '{
    "audio_url": "",
    "speech_models": ["universal-3-pro", "universal-2"],
    "language_detection": true,
    "speech_threshold": 0.5
  }'

# Poll for result (replace TRANSCRIPT_ID)
curl  \
  --header "Authorization: YOUR_API_KEY"

If the percentage of speech is below the threshold, text will be null and the response will contain an error message.

Speech threshold is supported for all languages, regions, and models.

To only transcribe files that contain at least a specified percentage of spoken audio, you can set the speech_threshold parameter. You can pass any value between 0 and 1.

If the percentage of speech in the audio file is below the provided threshold, the value of text is None and the response contains an error message:

Audio speech threshold 0.9461 is below the requested speech threshold value 1.0

A file must contain at least 30 seconds of audio for the amount of spoken audio to reliably be determined.

import assemblyai as aai

aai.settings.api_key = "<YOUR_API_KEY>"

# audio_file = "./local_file.mp3"
audio_file = ""

config = aai.TranscriptionConfig(
    speech_models=["universal-3-pro", "universal-2"],
    language_detection=True,
    speech_threshold=0.5
)

transcript = aai.Transcriber(config=config).transcribe(audio_file)

if transcript.status == "error":
  raise RuntimeError(f"Transcription failed: {transcript.error}")

print(transcript.text)

import requests
import time

base_url = ""

headers = {
    "authorization": "<YOUR_API_KEY>"
}

with open("./my-audio.mp3", "rb") as f:
  response = requests.post(base_url + "/v2/upload",
                          headers=headers,
                          data=f)

upload_url = response.json()["upload_url"]

data = {
    "audio_url": upload_url, # You can also use a URL to an audio or video file on the web
    "speech_models": ["universal-3-pro", "universal-2"],
    "language_detection": True,
    "speech_threshold": 0.5
}

url = base_url + "/v2/transcript"
response = requests.post(url, json=data, headers=headers)

transcript_id = response.json()['id']
polling_endpoint = base_url + "/v2/transcript/" + transcript_id

while True:
  transcription_result = requests.get(polling_endpoint, headers=headers).json()

  if transcription_result['status'] == 'completed':
    print(f"Transcript ID: {transcript_id}")
    break

  elif transcription_result['status'] == 'error':
    raise RuntimeError(f"Transcription failed: {transcription_result['error']}")

  else:
    time.sleep(3)

import { AssemblyAI } from "assemblyai";

const client = new AssemblyAI({
  apiKey: "<YOUR_API_KEY>",
});

// const audioFile = './local_file.mp3'
const audioFile = "";

const params = {
  audio: audioFile,
  speech_models: ["universal-3-pro", "universal-2"],
  language_detection: true,
  speech_threshold: 0.5,
};

const run = async () => {
  const transcript = await client.transcripts.transcribe(params);

  if (transcript.status === "error") {
    throw new Error(`Transcription failed: ${transcript.error}`);
  }

  console.log(transcript.text);
};

run();

import fs from "fs-extra";

const baseUrl = "";

const headers = {
  authorization: "<YOUR_API_KEY>",
};

const path = "./my-audio.mp3";
const audioData = await fs.readFile(path);
let res = await fetch(`${baseUrl}/v2/upload`, {
  method: "POST",
  headers,
  body: audioData,
});
if (!res.ok) throw new Error(`Error: ${res.status}`);
const uploadResponse = await res.json();
const uploadUrl = uploadResponse.upload_url;

const data = {
  audio_url: uploadUrl, // You can also use a URL to an audio or video file on the web
  speech_models: ["universal-3-pro", "universal-2"],
  language_detection: true,
  speech_threshold: 0.5,
};

const url = `${baseUrl}/v2/transcript`;
res = await fetch(url, {
  method: "POST",
  headers: { ...headers, "Content-Type": "application/json" },
  body: JSON.stringify(data),
});
if (!res.ok) throw new Error(`Error: ${res.status}`);
const response = await res.json();

const transcriptId = response.id;
const pollingEndpoint = `${baseUrl}/v2/transcript/${transcriptId}`;

while (true) {
  res = await fetch(pollingEndpoint, { headers });
  if (!res.ok) throw new Error(`Error: ${res.status}`);
  const transcriptionResult = await res.json();

  if (transcriptionResult.status === "completed") {
    console.log(transcriptionResult.text);
    break;
  } else if (transcriptionResult.status === "error") {
    throw new Error(`Transcription failed: ${transcriptionResult.error}`);
  } else {
    await new Promise((resolve) => setTimeout(resolve, 3000));
  }
}