title: Understanding blob url video streaming
body: <p>Many video stream websites, youtube for example, seem to have a blob url as their video source. Searching, I couldn't figure out how this works. For example...</p>
  
  <pre><code>&lt;video src="blob:https://www.youtube.com/ea375257-e9a8-4c3f-9cef-d8cf0f3ae53f"&gt;&lt;/video&gt;
  </code></pre>
  
  <p><a href="https://developer.mozilla.org/en-US/docs/Web/API/URL/createObjectURL" rel="noreferrer">URL.createObjectURL()</a>, the only way to get a blob url, takes in a <a href="https://developer.mozilla.org/en-US/docs/Web/API/File" rel="noreferrer">File</a>, <a href="https://developer.mozilla.org/en-US/docs/Web/API/Blob" rel="noreferrer">Blob</a>, or <a href="https://developer.mozilla.org/en-US/docs/Web/API/MediaSource" rel="noreferrer">MediaSource</a> object. Since the video is being streamed new data has to added constantly, and File and Blob don't seem to have that option, while MediaSource does, but is marked as an experimental feature on developer.mozilla.org...</p>
  
  <p>My question is how does this process, of streaming video through a blob url, work?</p>