Reorg folders and use core as ffmpeg from now on

2022-09-22 13:06:44 +08:00
parent 4f03229810
commit 20790e4fd2
138 changed files with 10505 additions and 1223 deletions
--- a/packages/util/examples/assets/StarWars3.wav
+++ b/packages/util/examples/assets/StarWars3.wav
--- a/packages/util/examples/assets/flame.avi
+++ b/packages/util/examples/assets/flame.avi
--- a/packages/util/examples/assets/triangle/audio.ogg
+++ b/packages/util/examples/assets/triangle/audio.ogg
--- a/packages/util/examples/assets/triangle/tmp.000.png
+++ b/packages/util/examples/assets/triangle/tmp.000.png
--- a/packages/util/examples/assets/triangle/tmp.001.png
+++ b/packages/util/examples/assets/triangle/tmp.001.png
--- a/packages/util/examples/assets/triangle/tmp.002.png
+++ b/packages/util/examples/assets/triangle/tmp.002.png
--- a/packages/util/examples/assets/triangle/tmp.003.png
+++ b/packages/util/examples/assets/triangle/tmp.003.png
--- a/packages/util/examples/assets/triangle/tmp.004.png
+++ b/packages/util/examples/assets/triangle/tmp.004.png
--- a/packages/util/examples/assets/triangle/tmp.005.png
+++ b/packages/util/examples/assets/triangle/tmp.005.png
--- a/packages/util/examples/assets/triangle/tmp.006.png
+++ b/packages/util/examples/assets/triangle/tmp.006.png
--- a/packages/util/examples/assets/triangle/tmp.007.png
+++ b/packages/util/examples/assets/triangle/tmp.007.png
--- a/packages/util/examples/assets/triangle/tmp.008.png
+++ b/packages/util/examples/assets/triangle/tmp.008.png
--- a/packages/util/examples/assets/triangle/tmp.009.png
+++ b/packages/util/examples/assets/triangle/tmp.009.png
--- a/packages/util/examples/assets/triangle/tmp.010.png
+++ b/packages/util/examples/assets/triangle/tmp.010.png
--- a/packages/util/examples/assets/triangle/tmp.011.png
+++ b/packages/util/examples/assets/triangle/tmp.011.png
--- a/packages/util/examples/assets/triangle/tmp.012.png
+++ b/packages/util/examples/assets/triangle/tmp.012.png
--- a/packages/util/examples/assets/triangle/tmp.013.png
+++ b/packages/util/examples/assets/triangle/tmp.013.png
--- a/packages/util/examples/assets/triangle/tmp.014.png
+++ b/packages/util/examples/assets/triangle/tmp.014.png
--- a/packages/util/examples/assets/triangle/tmp.015.png
+++ b/packages/util/examples/assets/triangle/tmp.015.png
--- a/packages/util/examples/assets/triangle/tmp.016.png
+++ b/packages/util/examples/assets/triangle/tmp.016.png
--- a/packages/util/examples/assets/triangle/tmp.017.png
+++ b/packages/util/examples/assets/triangle/tmp.017.png
--- a/packages/util/examples/assets/triangle/tmp.018.png
+++ b/packages/util/examples/assets/triangle/tmp.018.png
--- a/packages/util/examples/assets/triangle/tmp.019.png
+++ b/packages/util/examples/assets/triangle/tmp.019.png
--- a/packages/util/examples/assets/triangle/tmp.020.png
+++ b/packages/util/examples/assets/triangle/tmp.020.png
--- a/packages/util/examples/assets/triangle/tmp.021.png
+++ b/packages/util/examples/assets/triangle/tmp.021.png
--- a/packages/util/examples/assets/triangle/tmp.022.png
+++ b/packages/util/examples/assets/triangle/tmp.022.png
--- a/packages/util/examples/assets/triangle/tmp.023.png
+++ b/packages/util/examples/assets/triangle/tmp.023.png
--- a/packages/util/examples/assets/triangle/tmp.024.png
+++ b/packages/util/examples/assets/triangle/tmp.024.png
--- a/packages/util/examples/assets/triangle/tmp.025.png
+++ b/packages/util/examples/assets/triangle/tmp.025.png
--- a/packages/util/examples/assets/triangle/tmp.026.png
+++ b/packages/util/examples/assets/triangle/tmp.026.png
--- a/packages/util/examples/assets/triangle/tmp.027.png
+++ b/packages/util/examples/assets/triangle/tmp.027.png
--- a/packages/util/examples/assets/triangle/tmp.028.png
+++ b/packages/util/examples/assets/triangle/tmp.028.png
--- a/packages/util/examples/assets/triangle/tmp.029.png
+++ b/packages/util/examples/assets/triangle/tmp.029.png
--- a/packages/util/examples/assets/triangle/tmp.030.png
+++ b/packages/util/examples/assets/triangle/tmp.030.png
--- a/packages/util/examples/assets/triangle/tmp.031.png
+++ b/packages/util/examples/assets/triangle/tmp.031.png
--- a/packages/util/examples/assets/triangle/tmp.032.png
+++ b/packages/util/examples/assets/triangle/tmp.032.png
--- a/packages/util/examples/assets/triangle/tmp.033.png
+++ b/packages/util/examples/assets/triangle/tmp.033.png
--- a/packages/util/examples/assets/triangle/tmp.034.png
+++ b/packages/util/examples/assets/triangle/tmp.034.png
--- a/packages/util/examples/assets/triangle/tmp.035.png
+++ b/packages/util/examples/assets/triangle/tmp.035.png
--- a/packages/util/examples/assets/triangle/tmp.036.png
+++ b/packages/util/examples/assets/triangle/tmp.036.png
--- a/packages/util/examples/assets/triangle/tmp.037.png
+++ b/packages/util/examples/assets/triangle/tmp.037.png
--- a/packages/util/examples/assets/triangle/tmp.038.png
+++ b/packages/util/examples/assets/triangle/tmp.038.png
--- a/packages/util/examples/assets/triangle/tmp.039.png
+++ b/packages/util/examples/assets/triangle/tmp.039.png
--- a/packages/util/examples/assets/triangle/tmp.040.png
+++ b/packages/util/examples/assets/triangle/tmp.040.png
--- a/packages/util/examples/assets/triangle/tmp.041.png
+++ b/packages/util/examples/assets/triangle/tmp.041.png
--- a/packages/util/examples/assets/triangle/tmp.042.png
+++ b/packages/util/examples/assets/triangle/tmp.042.png
--- a/packages/util/examples/assets/triangle/tmp.043.png
+++ b/packages/util/examples/assets/triangle/tmp.043.png
--- a/packages/util/examples/assets/triangle/tmp.044.png
+++ b/packages/util/examples/assets/triangle/tmp.044.png
--- a/packages/util/examples/assets/triangle/tmp.045.png
+++ b/packages/util/examples/assets/triangle/tmp.045.png
--- a/packages/util/examples/assets/triangle/tmp.046.png
+++ b/packages/util/examples/assets/triangle/tmp.046.png
--- a/packages/util/examples/assets/triangle/tmp.047.png
+++ b/packages/util/examples/assets/triangle/tmp.047.png
--- a/packages/util/examples/assets/triangle/tmp.048.png
+++ b/packages/util/examples/assets/triangle/tmp.048.png
--- a/packages/util/examples/assets/triangle/tmp.049.png
+++ b/packages/util/examples/assets/triangle/tmp.049.png
--- a/packages/util/examples/assets/triangle/tmp.050.png
+++ b/packages/util/examples/assets/triangle/tmp.050.png
--- a/packages/util/examples/assets/triangle/tmp.051.png
+++ b/packages/util/examples/assets/triangle/tmp.051.png
--- a/packages/util/examples/assets/triangle/tmp.052.png
+++ b/packages/util/examples/assets/triangle/tmp.052.png
--- a/packages/util/examples/assets/triangle/tmp.053.png
+++ b/packages/util/examples/assets/triangle/tmp.053.png
--- a/packages/util/examples/assets/triangle/tmp.054.png
+++ b/packages/util/examples/assets/triangle/tmp.054.png
--- a/packages/util/examples/assets/triangle/tmp.055.png
+++ b/packages/util/examples/assets/triangle/tmp.055.png
--- a/packages/util/examples/assets/triangle/tmp.056.png
+++ b/packages/util/examples/assets/triangle/tmp.056.png
--- a/packages/util/examples/assets/triangle/tmp.057.png
+++ b/packages/util/examples/assets/triangle/tmp.057.png
--- a/packages/util/examples/assets/triangle/tmp.058.png
+++ b/packages/util/examples/assets/triangle/tmp.058.png
--- a/packages/util/examples/assets/triangle/tmp.059.png
+++ b/packages/util/examples/assets/triangle/tmp.059.png
--- a/packages/util/examples/browser/README.md
+++ b/packages/util/examples/browser/README.md
@@ -0,0 +1,22 @@
+Browser Examples
+==================
+
+To run this example, execute:
+
+```
+$ npm start
+```
+
+Visit http://localhost:3000/examples/browser/transcode.html
+
+
+Web Worker Examples
+==================
+
+To run the webworker example, execute:
+
+```
+$ npm run start:worker
+```
+
+Visit http://localhost:3000/examples/browser/transcode.worker.html
--- a/packages/util/examples/browser/concatDemuxer.html
+++ b/packages/util/examples/browser/concatDemuxer.html
@@ -0,0 +1,55 @@
+<html>
+  <head>
+    <script src="/dist/ffmpeg.dev.js"></script>
+    <style>
+      html,
+      body {
+        margin: 0;
+        width: 100%;
+        height: 100%;
+      }
+
+      body {
+        display: flex;
+        flex-direction: column;
+        align-items: center;
+      }
+    </style>
+  </head>
+
+  <body>
+    <h3>Select multiple video files to Concatenate</h3>
+    <video id="output-video" controls></video><br />
+    <input type="file" id="uploader" multiple />
+    <p id="message"></p>
+    <script>
+      const { createFFmpeg, fetchFile } = FFmpeg;
+      const ffmpeg = createFFmpeg({ log: true });
+
+      const transcode = async ({ target: { files } }) => {
+        const message = document.getElementById("message");
+        message.innerHTML = "Loading ffmpeg-core.js";
+        await ffmpeg.load();
+        message.innerHTML = "Start Concating";
+        const inputPaths = [];
+        for (const file of files) {
+          const { name } = file;
+          ffmpeg.FS('writeFile', name, await fetchFile(file));
+          inputPaths.push(`file ${name}`);
+        }
+        ffmpeg.FS('writeFile', 'concat_list.txt', inputPaths.join('\n'));
+        await ffmpeg.run('-f', 'concat', '-safe', '0', '-i', 'concat_list.txt', 'output.mp4');
+        message.innerHTML = "Complete Concating";
+        const data = ffmpeg.FS('readFile', 'output.mp4');
+        const video = document.getElementById("output-video");
+        video.src = URL.createObjectURL(
+          new Blob([data.buffer], {
+            type: "video/mp4"
+          })
+        );
+      };
+      const elm = document.getElementById("uploader");
+      elm.addEventListener("change", transcode);
+    </script>
+  </body>
+</html>
--- a/packages/util/examples/browser/image2video.html
+++ b/packages/util/examples/browser/image2video.html
@@ -0,0 +1,53 @@
+<html>
+  <head>
+    <script src="/dist/ffmpeg.dev.js"></script>
+    <style>
+      html, body {
+        margin: 0;
+        width: 100%;
+        height: 100%
+      }
+      body {
+        display: flex;
+        flex-direction: column;
+        align-items: center;
+      }
+    </style>
+  </head>
+  <body>
+    <h3>Click start to transcode images to mp4 (x264) and play!</h3>
+    <video id="output-video" controls></video><br/>
+    <button id="start-btn">Start</button>
+    <p id="message"></p>
+    <a href="https://github.com/ffmpegjs/ffmpeg.js/tree/master/examples/assets/triangle">Data Set</a>
+    <script>
+      const { createFFmpeg, fetchFile } = FFmpeg;
+      const ffmpeg = createFFmpeg({ log: true });
+
+      const image2video = async () => {
+        const message = document.getElementById('message');
+        message.innerHTML = 'Loading ffmpeg-core.js';
+        await ffmpeg.load();
+        message.innerHTML = 'Loading data';
+        ffmpeg.FS('writeFile', 'audio.ogg', await fetchFile('../assets/triangle/audio.ogg'));
+        for (let i = 0; i < 60; i += 1) {
+          const num = `00${i}`.slice(-3);
+          ffmpeg.FS('writeFile', `tmp.${num}.png`, await fetchFile(`../assets/triangle/tmp.${num}.png`));
+        }
+        message.innerHTML = 'Start transcoding';
+        await ffmpeg.run('-framerate', '30', '-pattern_type', 'glob', '-i', '*.png', '-i', 'audio.ogg', '-c:a', 'copy', '-shortest', '-c:v', 'libx264', '-pix_fmt', 'yuv420p', 'out.mp4');
+        const data = ffmpeg.FS('readFile', 'out.mp4');
+        ffmpeg.FS('unlink', 'audio.ogg')
+        for (let i = 0; i < 60; i += 1) {
+          const num = `00${i}`.slice(-3);
+          ffmpeg.FS('unlink', `tmp.${num}.png`);
+        }
+
+        const video = document.getElementById('output-video');
+        video.src = URL.createObjectURL(new Blob([data.buffer], { type: 'video/mp4' }));
+      }
+      const elm = document.getElementById('start-btn');
+      elm.addEventListener('click', image2video);
+    </script>
+  </body>
+</html>
--- a/packages/util/examples/browser/transcode.html
+++ b/packages/util/examples/browser/transcode.html
@@ -0,0 +1,57 @@
+<html>
+  <head>
+    <script src="/dist/ffmpeg.dev.js"></script>
+    <style>
+      html, body {
+        margin: 0;
+        width: 100%;
+        height: 100%
+      }
+      body {
+        display: flex;
+        flex-direction: column;
+        align-items: center;
+      }
+    </style>
+  </head>
+  <body>
+    <h3>Upload a video to transcode to mp4 (x264) and play!</h3>
+    <video id="output-video" controls></video><br/>
+    <input type="file" id="uploader">
+    <button onClick="cancel()">Cancel</button>
+    <p id="message"></p>
+    <script>
+      const { createFFmpeg, fetchFile } = FFmpeg;
+      let ffmpeg = null;
+
+      const transcode = async ({ target: { files } }) => {
+        if (ffmpeg === null) {
+          ffmpeg = createFFmpeg({ log: true });
+        }
+        const message = document.getElementById('message');
+        const { name } = files[0];
+        message.innerHTML = 'Loading ffmpeg-core.js';
+        if (!ffmpeg.isLoaded()) {
+          await ffmpeg.load();
+        }
+        ffmpeg.FS('writeFile', name, await fetchFile(files[0]));
+        message.innerHTML = 'Start transcoding';
+        await ffmpeg.run('-i', name,  'output.mp4');
+        message.innerHTML = 'Complete transcoding';
+        const data = ffmpeg.FS('readFile', 'output.mp4');
+
+        const video = document.getElementById('output-video');
+        video.src = URL.createObjectURL(new Blob([data.buffer], { type: 'video/mp4' }));
+      }
+      const elm = document.getElementById('uploader');
+      elm.addEventListener('change', transcode);
+
+      const cancel = () => {
+        try {
+          ffmpeg.exit();
+        } catch(e) {}
+        ffmpeg = null;
+      }
+    </script>
+  </body>
+</html>
--- a/packages/util/examples/browser/transcode.worker.html
+++ b/packages/util/examples/browser/transcode.worker.html
@@ -0,0 +1,48 @@
+<html>
+  <head>
+    <style>
+      html, body {
+        margin: 0;
+        width: 100%;
+        height: 100%
+      }
+      body {
+        display: flex;
+        flex-direction: column;
+        align-items: center;
+      }
+    </style>
+  </head>
+  <body>
+    <h3>Upload a video to transcode to mp4 (x264) and play!</h3>
+    <video id="output-video" controls></video><br/>
+    <input type="file" id="uploader">
+    <p id="message"></p>
+    <script type="module">
+        const worker = new Worker(new URL('./transcode.worker.js', import.meta.url).href);
+        worker.onmessage = (event) => {
+            const {data} = event;
+            message.innerHTML = 'Complete transcoding';
+            const video = document.getElementById('output-video');
+            video.src = URL.createObjectURL(new Blob([data.buffer], { type: 'video/mp4' }));
+        }
+        worker.onerror = (error) => console.log(error);
+        const transcode = async ({ target: { files } }) => {
+            const message = document.getElementById('message');
+            const [file] = files;
+
+            let name = file.name.split('.');
+            const inType = name.pop();
+            name = name.join();
+            const buffer = await file.arrayBuffer();
+            const outType = 'mp4';
+
+            worker.postMessage({name, inType, outType, buffer}, [buffer]);
+
+            message.innerHTML = 'Start transcoding';
+        }
+        const elm = document.getElementById('uploader');
+        elm.addEventListener('change', transcode);
+    </script>
+  </body>
+</html>
--- a/packages/util/examples/browser/transcode.worker.js
+++ b/packages/util/examples/browser/transcode.worker.js
@@ -0,0 +1,24 @@
+importScripts('/dist/ffmpeg.dev.js');
+const ffmpeg = self.FFmpeg.createFFmpeg({log: true});
+
+onmessage = async (event) => {
+    try {
+        const {buffer, name, inType, outType} = event.data;
+        if (!ffmpeg.isLoaded()) {
+            await ffmpeg.load();
+        }
+
+        ffmpeg.FS('writeFile', `${name}.${inType}`, new Uint8Array(buffer));
+        await ffmpeg.run('-i', `${name}.${inType}`, `${name}.${outType}`);
+        const data = ffmpeg.FS('readFile', `${name}.${outType}`);
+
+        postMessage({buffer: data.buffer, type: "result"}, [data.buffer]);
+
+        // delete files from memory
+        ffmpeg.FS('unlink', `${name}.${inType}`);
+        ffmpeg.FS('unlink', `${name}.${outType}`);
+    } catch (e) {
+        postMessage({type: "error", error: e});
+    }
+}
+
--- a/packages/util/examples/browser/trim.html
+++ b/packages/util/examples/browser/trim.html
@@ -0,0 +1,44 @@
+<html>
+  <head>
+    <script src="/dist/ffmpeg.dev.js"></script>
+    <style>
+      html, body {
+        margin: 0;
+        width: 100%;
+        height: 100%
+      }
+      body {
+        display: flex;
+        flex-direction: column;
+        align-items: center;
+      }
+    </style>
+  </head>
+  <body>
+    <h3>Upload a mp4 (x264) video and trim its first 1 seconds and play!</h3>
+    <video id="output-video" controls></video><br/>
+    <input type="file" id="uploader">
+    <p id="message"></p>
+    <script>
+      const { createFFmpeg, fetchFile } = FFmpeg;
+      const ffmpeg = createFFmpeg({ log: true });
+
+      const trim = async ({ target: { files } }) => {
+        const message = document.getElementById('message');
+        const { name } = files[0];
+        message.innerHTML = 'Loading ffmpeg-core.js';
+        await ffmpeg.load();
+        message.innerHTML = 'Start trimming';
+        ffmpeg.FS('writeFile', name, await fetchFile(files[0]));
+        await ffmpeg.run('-i', name, '-ss', '0', '-to', '1', 'output.mp4');
+        message.innerHTML = 'Complete trimming';
+        const data = ffmpeg.FS('readFile', 'output.mp4');
+
+        const video = document.getElementById('output-video');
+        video.src = URL.createObjectURL(new Blob([data.buffer], { type: 'video/mp4' }));
+      }
+      const elm = document.getElementById('uploader');
+      elm.addEventListener('change', trim);
+    </script>
+  </body>
+</html>
--- a/packages/util/examples/browser/webcam.html
+++ b/packages/util/examples/browser/webcam.html
@@ -0,0 +1,72 @@
+<html>
+  <head>
+    <script src="/dist/ffmpeg.dev.js"></script>
+    <style>
+      html, body {
+        margin: 0;
+        width: 100%;
+        height: 100%
+      }
+      body {
+        display: flex;
+        flex-direction: column;
+        align-items: center;
+      }
+    </style>
+  </head>
+  <body>
+    <h3>Record video from webcam and transcode to mp4 (x264) and play!</h3>
+    <div>
+      <video id="webcam" width="320px" height="180px"></video>
+      <video id="output-video" width="320px" height="180px" controls></video>
+    </div>
+    <button id="record" disabled>Start Recording</button>
+    <p id="message"></p>
+    <script>
+      const { createFFmpeg, fetchFile } = FFmpeg;
+      const ffmpeg = createFFmpeg({ log: true });
+
+      const webcam = document.getElementById('webcam');
+      const recordBtn = document.getElementById('record');
+      const startRecording = () => {
+        const rec = new MediaRecorder(webcam.srcObject);
+        const chunks = [];
+        
+        recordBtn.textContent = 'Stop Recording';
+        recordBtn.onclick = () => {
+          rec.stop();
+          recordBtn.textContent = 'Start Recording';
+          recordBtn.onclick = startRecording;
+        }
+
+        rec.ondataavailable = e => chunks.push(e.data);
+        rec.onstop = async () => {
+          transcode(new Uint8Array(await (new Blob(chunks)).arrayBuffer()));
+        };
+        rec.start();
+      };
+
+      (async () => {
+        webcam.srcObject = await navigator.mediaDevices.getUserMedia({ video: true, audio: true });
+        await webcam.play();
+        recordBtn.disabled = false;
+        recordBtn.onclick = startRecording;
+      })();
+
+      const transcode = async (webcamData) => {
+        const message = document.getElementById('message');
+        const name = 'record.webm';
+        message.innerHTML = 'Loading ffmpeg-core.js';
+        await ffmpeg.load();
+        message.innerHTML = 'Start transcoding';
+        ffmpeg.FS('writeFile', name, await fetchFile(webcamData));
+        await ffmpeg.run('-i', name,  'output.mp4');
+        message.innerHTML = 'Complete transcoding';
+        const data = ffmpeg.FS('readFile', 'output.mp4');
+
+        const video = document.getElementById('output-video');
+        video.src = URL.createObjectURL(new Blob([data.buffer], { type: 'video/mp4' }));
+      }
+    </script>
+  </body>
+</html>
--- a/packages/util/examples/node/concatDemuxer.js
+++ b/packages/util/examples/node/concatDemuxer.js
@@ -0,0 +1,13 @@
+const fs = require('fs');
+const { createFFmpeg, fetchFile } = require('../../src');
+
+const ffmpeg = createFFmpeg({ log: true });
+
+(async () => {
+  await ffmpeg.load();
+  ffmpeg.FS('writeFile', 'flame.avi', await fetchFile('../assets/flame.avi'));
+  ffmpeg.FS('writeFile', 'concat_list.txt', 'file flame.avi\nfile flame.avi');
+  await ffmpeg.run('-f', 'concat', '-safe', '0', '-i', 'concat_list.txt', 'flame.mp4');
+  await fs.promises.writeFile('flame.mp4', ffmpeg.FS('readFile', 'flame.mp4'));
+  process.exit(0);
+})();
--- a/packages/util/examples/node/hstack.js
+++ b/packages/util/examples/node/hstack.js
@@ -0,0 +1,12 @@
+const fs = require('fs');
+const { createFFmpeg, fetchFile } = require('../../src');
+
+const ffmpeg = createFFmpeg({ log: true });
+
+(async () => {
+  await ffmpeg.load();
+  ffmpeg.FS('writeFile', 'flame.avi', await fetchFile('../assets/flame.avi'));
+  await ffmpeg.run('-i', 'flame.avi', '-i', 'flame.avi', '-filter_complex', 'hstack', 'flame.mp4');
+  await fs.promises.writeFile('flame.mp4', ffmpeg.FS('readFile', 'flame.mp4'));
+  process.exit(0);
+})();
--- a/packages/util/examples/node/image2video.js
+++ b/packages/util/examples/node/image2video.js
@@ -0,0 +1,22 @@
+const fs = require('fs');
+const { createFFmpeg, fetchFile } = require('../../src');
+
+const ffmpeg = createFFmpeg({ log: true });
+
+(async () => {
+  await ffmpeg.load();
+  ffmpeg.FS('writeFile', 'audio.ogg', await fetchFile('../assets/triangle/audio.ogg'));
+  for (let i = 0; i < 60; i += 1) {
+    const num = `00${i}`.slice(-3);
+    ffmpeg.FS('writeFile', `tmp.${num}.png`, await fetchFile(`../assets/triangle/tmp.${num}.png`));
+  }
+  console.log(ffmpeg.FS('readdir', '/'));
+  await ffmpeg.run('-framerate', '30', '-pattern_type', 'glob', '-i', '*.png', '-i', 'audio.ogg', '-c:a', 'copy', '-shortest', '-c:v', 'libx264', '-pix_fmt', 'yuv420p', 'out.mp4');
+  await ffmpeg.FS('unlink', 'audio.ogg');
+  for (let i = 0; i < 60; i += 1) {
+    const num = `00${i}`.slice(-3);
+    await ffmpeg.FS('unlink', `tmp.${num}.png`);
+  }
+  await fs.promises.writeFile('out.mp4', ffmpeg.FS('readFile', 'out.mp4'));
+  process.exit(0);
+})();
--- a/packages/util/examples/node/multiple-output.js
+++ b/packages/util/examples/node/multiple-output.js
@@ -0,0 +1,14 @@
+const fs = require('fs');
+const { createFFmpeg, fetchFile } = require('../../src');
+
+const ffmpeg = createFFmpeg({ log: true });
+
+(async () => {
+  await ffmpeg.load();
+  ffmpeg.FS('writeFile', 'flame.avi', await fetchFile('../assets/flame.avi'));
+  await ffmpeg.run('-i', 'flame.avi', '-map', '0:v', '-r', '25', 'out_%06d.bmp');
+  ffmpeg.FS('readdir', '/').filter((p) => p.endsWith('.bmp')).forEach(async (p) => {
+    fs.writeFileSync(p, ffmpeg.FS('readFile', p));
+  });
+  process.exit(0);
+})();
--- a/packages/util/examples/node/transcode.js
+++ b/packages/util/examples/node/transcode.js
@@ -0,0 +1,14 @@
+const fs = require('fs');
+const { createFFmpeg, fetchFile } = require('../../src');
+
+const ffmpeg = createFFmpeg({
+  log: true,
+});
+
+(async () => {
+  await ffmpeg.load();
+  ffmpeg.FS('writeFile', 'flame.avi', await fetchFile('../assets/flame.avi'));
+  await ffmpeg.run('-i', 'flame.avi', 'flame.mp4');
+  await fs.promises.writeFile('flame.mp4', ffmpeg.FS('readFile', 'flame.mp4'));
+  process.exit(0);
+})();
--- a/packages/util/examples/node/trim.js
+++ b/packages/util/examples/node/trim.js
@@ -0,0 +1,12 @@
+const fs = require('fs');
+const { createFFmpeg, fetchFile } = require('../../src');
+
+const ffmpeg = createFFmpeg({ log: true });
+
+(async () => {
+  await ffmpeg.load();
+  ffmpeg.FS('writeFile', 'flame.avi', await fetchFile('../assets/flame.avi'));
+  await ffmpeg.run('-i', 'flame.avi', '-ss', '0', '-to', '1', 'flame_trim.avi');
+  await fs.promises.writeFile('flame_trim.avi', ffmpeg.FS('readFile', 'flame_trim.avi'));
+  process.exit(0);
+})();
--- a/packages/util/src/browser/defaultOptions.js
+++ b/packages/util/src/browser/defaultOptions.js
@@ -0,0 +1,10 @@
+import pkg from '../../package.json';
+
+/*
+ * Default options for browser environment
+ */
+const corePath = typeof process !== 'undefined' && process.env.NODE_ENV === 'development'
+  ? new URL('/node_modules/@ffmpeg/core/dist/ffmpeg-core.js', import.meta.url).href
+  : `https://unpkg.com/@ffmpeg/core@${pkg.devDependencies['@ffmpeg/core'].substring(1)}/dist/ffmpeg-core.js`;
+
+export default { corePath };
--- a/packages/util/src/browser/fetchFile.js
+++ b/packages/util/src/browser/fetchFile.js
@@ -0,0 +1,38 @@
+const readFromBlobOrFile = (blob) => (
+  new Promise((resolve, reject) => {
+    const fileReader = new FileReader();
+    fileReader.onload = () => {
+      resolve(fileReader.result);
+    };
+    fileReader.onerror = ({ target: { error: { code } } }) => {
+      reject(Error(`File could not be read! Code=${code}`));
+    };
+    fileReader.readAsArrayBuffer(blob);
+  })
+);
+
+// eslint-disable-next-line
+export const fetchFile = async (_data) => {
+  let data = _data;
+  if (typeof _data === 'undefined') {
+    return new Uint8Array();
+  }
+
+  if (typeof _data === 'string') {
+    /* From base64 format */
+    if (/data:_data\/([a-zA-Z]*);base64,([^"]*)/.test(_data)) {
+      data = atob(_data.split(',')[1])
+        .split('')
+        .map((c) => c.charCodeAt(0));
+    /* From remote server/URL */
+    } else {
+      const res = await fetch(new URL(_data, import.meta.url).href);
+      data = await res.arrayBuffer();
+    }
+  /* From Blob or File */
+  } else if (_data instanceof File || _data instanceof Blob) {
+    data = await readFromBlobOrFile(_data);
+  }
+
+  return new Uint8Array(data);
+};
--- a/packages/util/src/browser/getCreateFFmpegCore.js
+++ b/packages/util/src/browser/getCreateFFmpegCore.js
@@ -0,0 +1,114 @@
+/* eslint-disable no-undef */
+import { log } from '../utils/log';
+import {
+  CREATE_FFMPEG_CORE_IS_NOT_DEFINED,
+} from '../utils/errors';
+
+/*
+ * Fetch data from remote URL and convert to blob URL
+ * to avoid CORS issue
+ */
+const toBlobURL = async (url, mimeType) => {
+  log('info', `fetch ${url}`);
+  const buf = await (await fetch(url)).arrayBuffer();
+  log('info', `${url} file size = ${buf.byteLength} bytes`);
+  const blob = new Blob([buf], { type: mimeType });
+  const blobURL = URL.createObjectURL(blob);
+  log('info', `${url} blob URL = ${blobURL}`);
+  return blobURL;
+};
+
+// eslint-disable-next-line
+export const getCreateFFmpegCore = async ({
+  corePath: _corePath,
+  workerPath: _workerPath,
+  wasmPath: _wasmPath,
+}) => {
+  // in Web Worker context
+  // eslint-disable-next-line
+  if (typeof WorkerGlobalScope !== 'undefined' && self instanceof WorkerGlobalScope) {
+    if (typeof _corePath !== 'string') {
+      throw Error('corePath should be a string!');
+    }
+    const coreRemotePath = new URL(_corePath, import.meta.url).href;
+    const corePath = await toBlobURL(
+      coreRemotePath,
+      'application/javascript',
+    );
+    const wasmPath = await toBlobURL(
+      _wasmPath !== undefined ? _wasmPath : coreRemotePath.replace('ffmpeg-core.js', 'ffmpeg-core.wasm'),
+      'application/wasm',
+    );
+    const workerPath = await toBlobURL(
+      _workerPath !== undefined ? _workerPath : coreRemotePath.replace('ffmpeg-core.js', 'ffmpeg-core.worker.js'),
+      'application/javascript',
+    );
+    if (typeof createFFmpegCore === 'undefined') {
+      return new Promise((resolve) => {
+        globalThis.importScripts(corePath);
+        if (typeof createFFmpegCore === 'undefined') {
+          throw Error(CREATE_FFMPEG_CORE_IS_NOT_DEFINED(coreRemotePath));
+        }
+        log('info', 'ffmpeg-core.js script loaded');
+        resolve({
+          createFFmpegCore,
+          corePath,
+          wasmPath,
+          workerPath,
+        });
+      });
+    }
+    log('info', 'ffmpeg-core.js script is loaded already');
+    return Promise.resolve({
+      createFFmpegCore,
+      corePath,
+      wasmPath,
+      workerPath,
+    });
+  }
+  if (typeof _corePath !== 'string') {
+    throw Error('corePath should be a string!');
+  }
+  const coreRemotePath = new URL(_corePath, import.meta.url).href;
+  const corePath = await toBlobURL(
+    coreRemotePath,
+    'application/javascript',
+  );
+  const wasmPath = await toBlobURL(
+    coreRemotePath.replace('ffmpeg-core.js', 'ffmpeg-core.wasm'),
+    'application/wasm',
+  );
+  const workerPath = await toBlobURL(
+    coreRemotePath.replace('ffmpeg-core.js', 'ffmpeg-core.worker.js'),
+    'application/javascript',
+  );
+  if (typeof createFFmpegCore === 'undefined') {
+    return new Promise((resolve) => {
+      const script = document.createElement('script');
+      const eventHandler = () => {
+        script.removeEventListener('load', eventHandler);
+        if (typeof createFFmpegCore === 'undefined') {
+          throw Error(CREATE_FFMPEG_CORE_IS_NOT_DEFINED(coreRemotePath));
+        }
+        log('info', 'ffmpeg-core.js script loaded');
+        resolve({
+          createFFmpegCore,
+          corePath,
+          wasmPath,
+          workerPath,
+        });
+      };
+      script.src = corePath;
+      script.type = 'text/javascript';
+      script.addEventListener('load', eventHandler);
+      document.getElementsByTagName('head')[0].appendChild(script);
+    });
+  }
+  log('info', 'ffmpeg-core.js script is loaded already');
+  return Promise.resolve({
+    createFFmpegCore,
+    corePath,
+    wasmPath,
+    workerPath,
+  });
+};
--- a/packages/util/src/browser/index.js
+++ b/packages/util/src/browser/index.js
@@ -0,0 +1,5 @@
+import defaultOptions from './defaultOptions';
+import { getCreateFFmpegCore } from './getCreateFFmpegCore';
+import { fetchFile } from './fetchFile';
+
+export { defaultOptions, getCreateFFmpegCore, fetchFile };
--- a/packages/util/src/config.js
+++ b/packages/util/src/config.js
@@ -0,0 +1,50 @@
+module.exports = {
+  defaultArgs: [
+    /* args[0] is always the binary path */
+    './ffmpeg',
+    /* Disable interaction mode */
+    '-nostdin',
+    /* Force to override output file */
+    '-y',
+  ],
+  baseOptions: {
+    /* Flag to turn on/off log messages in console */
+    log: false,
+    /*
+     * Custom logger to get ffmpeg.wasm output messages.
+     * a sample logger looks like this:
+     *
+     * ```
+     * logger = ({ type, message }) => {
+     *   console.log(type, message);
+     * }
+     * ```
+     *
+     * type can be one of following:
+     *
+     * info: internal workflow debug messages
+     * fferr: ffmpeg native stderr output
+     * ffout: ffmpeg native stdout output
+     */
+    logger: () => {},
+    /*
+     * Progress handler to get current progress of ffmpeg command.
+     * a sample progress handler looks like this:
+     *
+     * ```
+     * progress = ({ ratio }) => {
+     *   console.log(ratio);
+     * }
+     * ```
+     *
+     * ratio is a float number between 0 to 1.
+     */
+    progress: () => {},
+    /*
+     * Path to find/download ffmpeg.wasm-core,
+     * this value should be overwriten by `defaultOptions` in
+     * each environment.
+     */
+    corePath: '',
+  },
+};
--- a/packages/util/src/createFFmpeg.js
+++ b/packages/util/src/createFFmpeg.js
@@ -0,0 +1,279 @@
+const { defaultArgs, baseOptions } = require('./config');
+const parseArgs = require('./utils/parseArgs');
+const { defaultOptions, getCreateFFmpegCore } = require('./node');
+const { version } = require('../package.json');
+
+const NO_LOAD = Error('ffmpeg.wasm is not ready, make sure you have completed load().');
+
+module.exports = (_options = {}) => {
+  const {
+    log: optLog,
+    logger,
+    progress: optProgress,
+    ...options
+  } = {
+    ...baseOptions,
+    ...defaultOptions,
+    ..._options,
+  };
+  let Core = null;
+  let ffmpeg = null;
+  let runResolve = null;
+  let runReject = null;
+  let running = false;
+  let customLogger = () => {};
+  let logging = optLog;
+  let progress = optProgress;
+  let duration = 0;
+  let frames = 0;
+  let readFrames = false;
+  let ratio = 0;
+
+  const detectCompletion = (message) => {
+    if (message === 'FFMPEG_END' && runResolve !== null) {
+      runResolve();
+      runResolve = null;
+      runReject = null;
+      running = false;
+    }
+  };
+  const log = (type, message) => {
+    customLogger({ type, message });
+    if (logging) {
+      console.log(`[${type}] ${message}`);
+    }
+  };
+  const ts2sec = (ts) => {
+    const [h, m, s] = ts.split(':');
+    return (parseFloat(h) * 60 * 60) + (parseFloat(m) * 60) + parseFloat(s);
+  };
+  const parseProgress = (message, prog) => {
+    if (typeof message === 'string') {
+      if (message.startsWith('  Duration')) {
+        const ts = message.split(', ')[0].split(': ')[1];
+        const d = ts2sec(ts);
+        prog({ duration: d, ratio });
+        if (duration === 0 || duration > d) {
+          duration = d;
+          readFrames = true;
+        }
+      } else if (readFrames && message.startsWith('    Stream')) {
+        const match = message.match(/([\d.]+) fps/);
+        if (match) {
+          const fps = parseFloat(match[1]);
+          frames = duration * fps;
+        } else {
+          frames = 0;
+        }
+        readFrames = false;
+      } else if (message.startsWith('frame') || message.startsWith('size')) {
+        const ts = message.split('time=')[1].split(' ')[0];
+        const t = ts2sec(ts);
+        const match = message.match(/frame=\s*(\d+)/);
+        if (frames && match) {
+          const f = parseFloat(match[1]);
+          ratio = Math.min(f / frames, 1);
+        } else {
+          ratio = t / duration;
+        }
+        prog({ ratio, time: t });
+      } else if (message.startsWith('video:')) {
+        prog({ ratio: 1 });
+        duration = 0;
+      }
+    }
+  };
+  const parseMessage = ({ type, message }) => {
+    log(type, message);
+    parseProgress(message, progress);
+    detectCompletion(message);
+  };
+
+  /*
+   * Load ffmpeg.wasm-core script.
+   * In browser environment, the ffmpeg.wasm-core script is fetch from
+   * CDN and can be assign to a local path by assigning `corePath`.
+   * In node environment, we use dynamic require and the default `corePath`
+   * is `$ffmpeg/core`.
+   *
+   * Typically the load() func might take few seconds to minutes to complete,
+   * better to do it as early as possible.
+   *
+   */
+  const load = async () => {
+    log('info', 'load ffmpeg-core');
+    if (Core === null) {
+      log('info', 'loading ffmpeg-core');
+      /*
+       * In node environment, all paths are undefined as there
+       * is no need to set them.
+       */
+      const {
+        createFFmpegCore,
+        corePath,
+        workerPath,
+        wasmPath,
+      } = await getCreateFFmpegCore(options);
+      Core = await createFFmpegCore({
+        /*
+         * Assign mainScriptUrlOrBlob fixes chrome extension web worker issue
+         * as there is no document.currentScript in the context of content_scripts
+         */
+        mainScriptUrlOrBlob: corePath,
+        printErr: (message) => parseMessage({ type: 'fferr', message }),
+        print: (message) => parseMessage({ type: 'ffout', message }),
+        /*
+         * locateFile overrides paths of files that is loaded by main script (ffmpeg-core.js).
+         * It is critical for browser environment and we override both wasm and worker paths
+         * as we are using blob URL instead of original URL to avoid cross origin issues.
+         */
+        locateFile: (path, prefix) => {
+          if (typeof window !== 'undefined' || typeof WorkerGlobalScope !== 'undefined') {
+            if (typeof wasmPath !== 'undefined'
+              && path.endsWith('ffmpeg-core.wasm')) {
+              return wasmPath;
+            }
+            if (typeof workerPath !== 'undefined'
+              && path.endsWith('ffmpeg-core.worker.js')) {
+              return workerPath;
+            }
+          }
+          return prefix + path;
+        },
+      });
+      ffmpeg = Core.cwrap(options.mainName || 'proxy_main', 'number', ['number', 'number']);
+      log('info', 'ffmpeg-core loaded');
+    } else {
+      throw Error('ffmpeg.wasm was loaded, you should not load it again, use ffmpeg.isLoaded() to check next time.');
+    }
+  };
+
+  /*
+   * Determine whether the Core is loaded.
+   */
+  const isLoaded = () => Core !== null;
+
+  /*
+   * Run ffmpeg command.
+   * This is the major function in ffmpeg.wasm, you can just imagine it
+   * as ffmpeg native cli and what you need to pass is the same.
+   *
+   * For example, you can convert native command below:
+   *
+   * ```
+   * $ ffmpeg -i video.avi -c:v libx264 video.mp4
+   * ```
+   *
+   * To
+   *
+   * ```
+   * await ffmpeg.run('-i', 'video.avi', '-c:v', 'libx264', 'video.mp4');
+   * ```
+   *
+   */
+  const run = (..._args) => {
+    log('info', `run ffmpeg command: ${_args.join(' ')}`);
+    if (Core === null) {
+      throw NO_LOAD;
+    } else if (running) {
+      throw Error('ffmpeg.wasm can only run one command at a time');
+    } else {
+      running = true;
+      return new Promise((resolve, reject) => {
+        const args = [...defaultArgs, ..._args].filter((s) => s.length !== 0);
+        runResolve = resolve;
+        runReject = reject;
+        ffmpeg(...parseArgs(Core, args));
+      });
+    }
+  };
+
+  /*
+   * Run FS operations.
+   * For input/output file of ffmpeg.wasm, it is required to save them to MEMFS
+   * first so that ffmpeg.wasm is able to consume them. Here we rely on the FS
+   * methods provided by Emscripten.
+   *
+   * Common methods to use are:
+   * ffmpeg.FS('writeFile', 'video.avi', new Uint8Array(...)): writeFile writes
+   * data to MEMFS. You need to use Uint8Array for binary data.
+   * ffmpeg.FS('readFile', 'video.mp4'): readFile from MEMFS.
+   * ffmpeg.FS('unlink', 'video.map'): delete file from MEMFS.
+   *
+   * For more info, check https://emscripten.org/docs/api_reference/Filesystem-API.html
+   *
+   */
+  const FS = (method, ...args) => {
+    log('info', `run FS.${method} ${args.map((arg) => (typeof arg === 'string' ? arg : `<${arg.length} bytes binary file>`)).join(' ')}`);
+    if (Core === null) {
+      throw NO_LOAD;
+    } else {
+      let ret = null;
+      try {
+        ret = Core.FS[method](...args);
+      } catch (e) {
+        if (method === 'readdir') {
+          throw Error(`ffmpeg.FS('readdir', '${args[0]}') error. Check if the path exists, ex: ffmpeg.FS('readdir', '/')`);
+        } else if (method === 'readFile') {
+          throw Error(`ffmpeg.FS('readFile', '${args[0]}') error. Check if the path exists`);
+        } else {
+          throw Error('Oops, something went wrong in FS operation.');
+        }
+      }
+      return ret;
+    }
+  };
+
+  /**
+   * forcibly terminate the ffmpeg program.
+   */
+  const exit = () => {
+    if (Core === null) {
+      throw NO_LOAD;
+    } else {
+      // if there's any pending runs, reject them
+      if (runReject) {
+        runReject('ffmpeg has exited');
+      }
+      running = false;
+      try {
+        Core.exit(1);
+      } catch (err) {
+        log(err.message);
+        if (runReject) {
+          runReject(err);
+        }
+      } finally {
+        Core = null;
+        ffmpeg = null;
+        runResolve = null;
+        runReject = null;
+      }
+    }
+  };
+
+  const setProgress = (_progress) => {
+    progress = _progress;
+  };
+
+  const setLogger = (_logger) => {
+    customLogger = _logger;
+  };
+
+  const setLogging = (_logging) => {
+    logging = _logging;
+  };
+
+  log('info', `use ffmpeg.wasm v${version}`);
+
+  return {
+    setProgress,
+    setLogger,
+    setLogging,
+    load,
+    isLoaded,
+    run,
+    exit,
+    FS,
+  };
+};
--- a/packages/util/src/index.d.ts
+++ b/packages/util/src/index.d.ts
@@ -0,0 +1,120 @@
+export const FS: {
+    writeFile: (fileName: string, binaryData: Uint8Array | string) => void,
+    readFile: (fileName: string) => Uint8Array,
+    readdir: (pathName: string) => string[],
+    unlink: (fileName: string) => void,
+    mkdir: (fileName: string) => void,
+}
+
+type FSMethodNames = { [K in keyof typeof FS]: (typeof FS)[K] extends (...args: any[]) => any ? K : never }[keyof typeof FS];
+type FSMethodArgs = { [K in FSMethodNames]: Parameters<(typeof FS)[K]> };
+type FSMethodReturn = { [K in FSMethodNames]: ReturnType<(typeof FS)[K]> };
+
+type LogCallback = (logParams: { type: string; message: string }) => any;
+type ProgressCallback = (progressParams: { ratio: number }) => any;
+
+export interface CreateFFmpegOptions {
+    /** path for ffmpeg-core.js script */
+    corePath?: string;
+    /** path for ffmpeg-worker.js script */
+    workerPath?: string;
+    /** path for ffmpeg-core.wasm script */
+    wasmPath?: string;
+    /** a boolean to turn on all logs, default is false */
+    log?: boolean;
+    /** a function to get log messages, a quick example is ({ message }) => console.log(message) */
+    logger?: LogCallback;
+    /** a function to trace the progress, a quick example is p => console.log(p) */
+    progress?: ProgressCallback;
+    /** name of the main function of the ffmpeg-core.js script */
+    mainName?: string;
+}
+
+export interface FFmpeg {
+    /*
+     * Load ffmpeg.wasm-core script.
+     * In browser environment, the ffmpeg.wasm-core script is fetch from
+     * CDN and can be assign to a local path by assigning `corePath`.
+     * In node environment, we use dynamic require and the default `corePath`
+     * is `$ffmpeg/core`.
+     *
+     * Typically the load() func might take few seconds to minutes to complete,
+     * better to do it as early as possible.
+     *
+     */
+    load(): Promise<void>;
+    /*
+     * Determine whether the Core is loaded.
+     */
+    isLoaded(): boolean;
+    /*
+     * Run ffmpeg command.
+     * This is the major function in ffmpeg.wasm, you can just imagine it
+     * as ffmpeg native cli and what you need to pass is the same.
+     *
+     * For example, you can convert native command below:
+     *
+     * ```
+     * $ ffmpeg -i video.avi -c:v libx264 video.mp4
+     * ```
+     *
+     * To
+     *
+     * ```
+     * await ffmpeg.run('-i', 'video.avi', '-c:v', 'libx264', 'video.mp4');
+     * ```
+     *
+     */
+    run(...args: string[]): Promise<void>;
+    /*
+     * Run FS operations.
+     * For input/output file of ffmpeg.wasm, it is required to save them to MEMFS
+     * first so that ffmpeg.wasm is able to consume them. Here we rely on the FS
+     * methods provided by Emscripten.
+     *
+     * Common methods to use are:
+     * ffmpeg.FS('writeFile', 'video.avi', new Uint8Array(...)): writeFile writes
+     * data to MEMFS. You need to use Uint8Array for binary data.
+     * ffmpeg.FS('readFile', 'video.mp4'): readFile from MEMFS.
+     * ffmpeg.FS('unlink', 'video.map'): delete file from MEMFS.
+     *
+     * For more info, check https://emscripten.org/docs/api_reference/Filesystem-API.html
+     *
+     */
+    FS<Method extends FSMethodNames>(method: Method, ...args: FSMethodArgs[Method]): FSMethodReturn[Method];
+    setProgress(progress: ProgressCallback): void;
+    setLogger(log: LogCallback): void;
+    setLogging(logging: boolean): void;
+    exit(): void;
+}
+
+/*
+ * Create ffmpeg instance.
+ * Each ffmpeg instance owns an isolated MEMFS and works
+ * independently.
+ *
+ * For example:
+ *
+ * ```
+ * const ffmpeg = createFFmpeg({
+ *  log: true,
+ *  logger: () => {},
+ *  progress: () => {},
+ *  corePath: '',
+ * })
+ * ```
+ *
+ * For the usage of these four arguments, check config.js
+ *
+ */
+export function createFFmpeg(options?: CreateFFmpegOptions): FFmpeg;
+/*
+ * Helper function for fetching files from various resource.
+ * Sometimes the video/audio file you want to process may located
+ * in a remote URL and somewhere in your local file system.
+ *
+ * This helper function helps you to fetch to file and return an
+ * Uint8Array variable for ffmpeg.wasm to consume.
+ *
+ */
+export function fetchFile(data: string | Buffer | Blob | File): Promise<Uint8Array>;
--- a/packages/util/src/index.js
+++ b/packages/util/src/index.js
@@ -0,0 +1,36 @@
+require('regenerator-runtime/runtime');
+const createFFmpeg = require('./createFFmpeg');
+const { fetchFile } = require('./node');
+
+module.exports = {
+  /*
+   * Create ffmpeg instance.
+   * Each ffmpeg instance owns an isolated MEMFS and works
+   * independently.
+   *
+   * For example:
+   *
+   * ```
+   * const ffmpeg = createFFmpeg({
+   *  log: true,
+   *  logger: () => {},
+   *  progress: () => {},
+   *  corePath: '',
+   * })
+   * ```
+   *
+   * For the usage of these four arguments, check config.js
+   *
+   */
+  createFFmpeg,
+  /*
+   * Helper function for fetching files from various resource.
+   * Sometimes the video/audio file you want to process may located
+   * in a remote URL and somewhere in your local file system.
+   *
+   * This helper function helps you to fetch to file and return an
+   * Uint8Array variable for ffmpeg.wasm to consume.
+   *
+   */
+  fetchFile,
+};
--- a/packages/util/src/node/defaultOptions.js
+++ b/packages/util/src/node/defaultOptions.js
@@ -0,0 +1,6 @@
+/*
+ * Default options for node environment
+ */
+module.exports = {
+  corePath: '@ffmpeg/core',
+};
--- a/packages/util/src/node/fetchFile.js
+++ b/packages/util/src/node/fetchFile.js
@@ -0,0 +1,33 @@
+const util = require('util');
+const fs = require('fs');
+const fetch = require('node-fetch');
+const isURL = require('is-url');
+
+module.exports = async (_data) => {
+  let data = _data;
+  if (typeof _data === 'undefined') {
+    return new Uint8Array();
+  }
+
+  if (typeof _data === 'string') {
+    /* From remote URL/server */
+    if (isURL(_data)
+      || _data.startsWith('moz-extension://')
+      || _data.startsWith('chrome-extension://')
+      || _data.startsWith('file://')) {
+      const res = await fetch(_data);
+      data = await res.arrayBuffer();
+    /* From base64 format */
+    } else if (/data:_data\/([a-zA-Z]*);base64,([^"]*)/.test(_data)) {
+      data = Buffer.from(_data.split(',')[1], 'base64');
+    /* From local file path */
+    } else {
+      data = await util.promisify(fs.readFile)(_data);
+    }
+    /* From Buffer */
+  } else if (Buffer.isBuffer(_data)) {
+    data = _data;
+  }
+
+  return new Uint8Array(data);
+};
--- a/packages/util/src/node/getCreateFFmpegCore.js
+++ b/packages/util/src/node/getCreateFFmpegCore.js
@@ -0,0 +1,7 @@
+const { log } = require('../utils/log');
+
+module.exports = ({ corePath }) => new Promise((resolve) => {
+  log('info', `fetch ffmpeg.wasm-core script from ${corePath}`);
+  // eslint-disable-next-line import/no-dynamic-require
+  resolve({ createFFmpegCore: require(corePath) });
+});
--- a/packages/util/src/node/index.js
+++ b/packages/util/src/node/index.js
@@ -0,0 +1,9 @@
+const defaultOptions = require('./defaultOptions');
+const getCreateFFmpegCore = require('./getCreateFFmpegCore');
+const fetchFile = require('./fetchFile');
+
+module.exports = {
+  defaultOptions,
+  getCreateFFmpegCore,
+  fetchFile,
+};
--- a/packages/util/src/utils/errors.js
+++ b/packages/util/src/utils/errors.js
@@ -0,0 +1,11 @@
+const CREATE_FFMPEG_CORE_IS_NOT_DEFINED = (corePath) => (`
+createFFmpegCore is not defined. ffmpeg.wasm is unable to find createFFmpegCore after loading ffmpeg-core.js from ${corePath}. Use another URL when calling createFFmpeg():
+
+const ffmpeg = createFFmpeg({
+  corePath: 'http://localhost:3000/ffmpeg-core.js',
+});
+`);
+
+module.exports = {
+  CREATE_FFMPEG_CORE_IS_NOT_DEFINED,
+};
--- a/packages/util/src/utils/log.js
+++ b/packages/util/src/utils/log.js
@@ -0,0 +1,24 @@
+let logging = false;
+let customLogger = () => {};
+
+const setLogging = (_logging) => {
+  logging = _logging;
+};
+
+const setCustomLogger = (logger) => {
+  customLogger = logger;
+};
+
+const log = (type, message) => {
+  customLogger({ type, message });
+  if (logging) {
+    console.log(`[${type}] ${message}`);
+  }
+};
+
+module.exports = {
+  logging,
+  setLogging,
+  setCustomLogger,
+  log,
+};
--- a/packages/util/src/utils/parseArgs.js
+++ b/packages/util/src/utils/parseArgs.js
@@ -0,0 +1,10 @@
+module.exports = (Core, args) => {
+  const argsPtr = Core._malloc(args.length * Uint32Array.BYTES_PER_ELEMENT);
+  args.forEach((s, idx) => {
+    const sz = Core.lengthBytesUTF8(s) + 1;
+    const buf = Core._malloc(sz);
+    Core.stringToUTF8(s, buf, sz);
+    Core.setValue(argsPtr + (Uint32Array.BYTES_PER_ELEMENT * idx), buf, 'i32');
+  });
+  return [args.length, argsPtr];
+};
--- a/packages/util/tests/.eslintrc
+++ b/packages/util/tests/.eslintrc
@@ -0,0 +1,6 @@
+{
+  "rules": {
+    "no-undef": 0,
+    "camelcase": 0
+  }
+}
--- a/packages/util/tests/constants.js
+++ b/packages/util/tests/constants.js
@@ -0,0 +1,19 @@
+const TIMEOUT = 60000;
+const IS_BROWSER = typeof window !== 'undefined' && typeof window.document !== 'undefined';
+const OPTIONS = {
+  corePath: IS_BROWSER ? 'http://localhost:3000/node_modules/@ffmpeg/core/dist/ffmpeg-core.js' : '@ffmpeg/core',
+};
+const FLAME_MP4_LENGTH = 100374;
+const META_FLAME_MP4_LENGTH = 100408;
+const META_FLAME_MP4_LENGTH_NO_SPACE = 100404;
+
+if (typeof module !== 'undefined') {
+  module.exports = {
+    TIMEOUT,
+    IS_BROWSER,
+    OPTIONS,
+    FLAME_MP4_LENGTH,
+    META_FLAME_MP4_LENGTH,
+    META_FLAME_MP4_LENGTH_NO_SPACE,
+  };
+}
--- a/packages/util/tests/ffmpeg.test.html
+++ b/packages/util/tests/ffmpeg.test.html
@@ -0,0 +1,21 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+  <meta charset="UTF-8">
+  <title>FFmpeg Unit Test</title>
+  <link rel="stylesheet" href="../node_modules/mocha/mocha.css">
+</head>
+<body>
+  <div id="mocha"></div>
+  <script src="../node_modules/mocha/mocha.js"></script>
+  <script src="../node_modules/chai/chai.js"></script>
+  <script src="../dist/ffmpeg.dev.js"></script>
+  <script src="./constants.js"></script>
+  <script>mocha.setup('bdd');</script>
+  <script src="./ffmpeg.test.js"></script>
+  <script>
+    window.expect = chai.expect;
+    mocha.run();
+  </script>
+</body>
+</html>
--- a/packages/util/tests/ffmpeg.test.js
+++ b/packages/util/tests/ffmpeg.test.js
@@ -0,0 +1,69 @@
+const { createFFmpeg } = FFmpeg;
+
+describe('FS()', () => {
+  const ffmpeg = createFFmpeg(OPTIONS);
+  before(async function cb() {
+    this.timeout(0);
+    await ffmpeg.load();
+  });
+
+  it('should throw error when readdir for invalid path ', () => {
+    expect(() => ffmpeg.FS('readdir', '/invalid')).to.throw(/readdir/);
+  });
+  it('should throw error when readFile for invalid path ', () => {
+    expect(() => ffmpeg.FS('readFile', '/invalid')).to.throw(/readFile/);
+  });
+  it('should throw an default error ', () => {
+    expect(() => ffmpeg.FS('unlink', '/invalid')).to.throw(/Oops/);
+  });
+});
+
+describe('load()', () => {
+  it('should throw error when corePath is not a string', async () => {
+    const ffmpeg = createFFmpeg({ ...OPTIONS, corePath: null });
+
+    try {
+      await ffmpeg.load();
+    } catch (e) {
+      expect(e).to.be.an('Error');
+    }
+  });
+  it('should throw error when not called before FS() and run()', () => {
+    const ffmpeg = createFFmpeg(OPTIONS);
+    expect(() => ffmpeg.FS('readdir', 'dummy')).to.throw();
+    expect(() => ffmpeg.run('-h')).to.throw();
+  });
+
+  it('should throw error when running load() more than once', async () => {
+    const ffmpeg = createFFmpeg(OPTIONS);
+    await ffmpeg.load();
+    try {
+      await ffmpeg.load();
+    } catch (e) {
+      expect(e).to.be.an('Error');
+    }
+  }).timeout(TIMEOUT);
+});
+
+describe('isLoaded()', () => {
+  it('should return true when loaded', async () => {
+    const ffmpeg = createFFmpeg(OPTIONS);
+    await ffmpeg.load();
+    expect(ffmpeg.isLoaded()).to.equal(true);
+  }).timeout(TIMEOUT);
+});
+
+describe('run()', () => {
+  it('should not allow to run two command at the same time', async () => {
+    const ffmpeg = createFFmpeg(OPTIONS);
+    await ffmpeg.load();
+    ffmpeg.run('-h');
+    setTimeout(() => {
+      try {
+        ffmpeg.run('-h');
+      } catch (e) {
+        expect(e).to.be.an(Error);
+      }
+    }, 500);
+  }).timeout(TIMEOUT);
+});