Whisper-large-v3-turbo với Cloudflare Workers AI Whisper-large-v3-turbo with Cloudflare Workers AI ហ្វេសប៊ូតុង-v3-turbo ជាមួយ Cloudflare Workers AI

npm create cloudflare@latest -- whisper-tutorial

yarn create cloudflare whisper-tutorial

pnpm create cloudflare@latest whisper-tutorial

cd whisper-tutorial

{

  "ai": {

    "binding": "AI"

  }

}

[ai]

binding = "AI"

{

  "compatibility_flags": [

    "nodejs_compat"

  ],

  // Set this to today's date

  "compatibility_date": "2026-06-10"

}

compatibility_flags = [ "nodejs_compat" ]

# Set this to today's date

compatibility_date = "2026-06-10"

import { Buffer } from "node:buffer";

import type { Ai } from "workers-ai";


export interface Env {

  AI: Ai;

  // If needed, add your KV namespace for storing transcripts.

  // MY_KV_NAMESPACE: KVNamespace;

}


/**

 * Fetches the audio file from the provided URL and splits it into chunks.

 * This function explicitly follows redirects.

 *

 * @param audioUrl - The URL of the audio file.

 * @returns An array of ArrayBuffers, each representing a chunk of the audio.

 */

async function getAudioChunks(audioUrl: string): Promise<ArrayBuffer[]> {

  const response = await fetch(audioUrl, { redirect: "follow" });

  if (!response.ok) {

    throw new Error(`Failed to fetch audio: ${response.status}`);

  }

  const arrayBuffer = await response.arrayBuffer();


  // Example: Split the audio into 1MB chunks.

  const chunkSize = 1024 * 1024; // 1MB

  const chunks: ArrayBuffer[] = [];

  for (let i = 0; i < arrayBuffer.byteLength; i += chunkSize) {

    const chunk = arrayBuffer.slice(i, i + chunkSize);

    chunks.push(chunk);

  }

  return chunks;

}


/**

 * Transcribes a single audio chunk using the Whisper‑large‑v3‑turbo model.

 * The function converts the audio chunk to a Base64-encoded string and

 * sends it to the model via the AI binding.

 *

 * @param chunkBuffer - The audio chunk as an ArrayBuffer.

 * @param env - The Cloudflare Worker environment, including the AI binding.

 * @returns The transcription text from the model.

 */

async function transcribeChunk(

  chunkBuffer: ArrayBuffer,

  env: Env,

): Promise<string> {

  const base64 = Buffer.from(chunkBuffer, "binary").toString("base64");

  const res = await env.AI.run("@cf/openai/whisper-large-v3-turbo", {

    audio: base64,

    // Optional parameters (uncomment and set if needed):

    // task: "transcribe",   // or "translate"

    // language: "en",

    // vad_filter: "false",

    // initial_prompt: "Provide context if needed.",

    // prefix: "Transcription:",

  });

  return res.text; // Assumes the transcription result includes a "text" property.

}


/**

 * The main fetch handler. It extracts the 'url' query parameter, fetches the audio,

 * processes it in chunks, and returns the full transcription.

 */

export default {

  async fetch(

    request: Request,

    env: Env,

    ctx: ExecutionContext,

  ): Promise<Response> {

    // Extract the audio URL from the query parameters.

    const { searchParams } = new URL(request.url);

    const audioUrl = searchParams.get("url");


    if (!audioUrl) {

      return new Response("Missing 'url' query parameter", { status: 400 });

    }


    // Get the audio chunks.

    const audioChunks: ArrayBuffer[] = await getAudioChunks(audioUrl);

    let fullTranscript = "";


    // Process each chunk and build the full transcript.

    for (const chunk of audioChunks) {

      try {

        const transcript = await transcribeChunk(chunk, env);

        fullTranscript += transcript + "\n";

      } catch (error) {

        fullTranscript += "[Error transcribing chunk]\n";

      }

    }


    return new Response(fullTranscript, {

      headers: { "Content-Type": "text/plain" },

    });

  },

} satisfies ExportedHandler<Env>;

npx wrangler dev

curl "http://localhost:8787?url=https://raw.githubusercontent.com/your-username/your-repo/main/your-audio-file.mp3"

npx wrangler deploy

curl "https://<your-worker-subdomain>.workers.dev?url=https://raw.githubusercontent.com/your-username/your-repo/main/your-audio-file.mp3"

This is the transcript of the audio...

{"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"item":{"@id":"/directory/","name":"Directory"}},{"@type":"ListItem","position":2,"item":{"@id":"/workers-ai/","name":"Workers AI"}},{"@type":"ListItem","position":3,"item":{"@id":"/workers-ai/guides/","name":"Guides"}},{"@type":"ListItem","position":4,"item":{"@id":"/workers-ai/guides/tutorials/","name":"Tutorials"}},{"@type":"ListItem","position":5,"item":{"@id":"/workers-ai/guides/tutorials/build-a-workers-ai-whisper-with-chunking/","name":"Whisper-large-v3-turbo with Cloudflare Workers AI"}}]}