What does gs protocol mean? : <p>I'm playing with <a href="https://cloud.google.com/speech/" rel="noreferrer">Google Speech Recognition API</a></p>

<p>After a successfully <a href="https://cloud.google.com/speech/docs/getting-started" rel="noreferrer">Getting started</a> I'm trying to understand and made some changes in this first example but I don't know what "gs" protocol is and how to set it to use my own audio file.</p>

<p>sync-request.json</p>

<pre><code>{
  "config": {
      "encoding":"FLAC",
      "sample_rate": 16000
  },
  "audio": {
      "uri":"gs://cloud-samples-tests/speech/brooklyn.flac"
  }
}
</code></pre>

<p>I tried to change gs protocol to http protocol but doesn't work.  </p>

<p>Thanks in advance.</p>
