十六. HTML5 流媒体技术

1. 安装FFmpeg

• 苹果平台: 推荐使用brew来安装
  • 命令行安装 brew
  • brew install ffmpeg
• window平台用chocolatey包管理工具,来安装
  • 命令行安装 chocolatey @"%SystemRoot%\System32\WindowsPowerShell\v1.0\powershell.exe" -NoProfile -InputFormat None -ExecutionPolicy Bypass -Command "[System.Net.ServicePointManager]::SecurityProtocol = 3072; iex ((New-Object System.Net.WebClient).DownloadString('https://chocolatey.org/install.ps1'))" && SET "PATH=%PATH%;%ALLUSERSPROFILE%\chocolatey\bin"
  • choco install ffmpeg
• linux平台安装
  • sudo apt install ffmpeg

2. 音频

2.1

    (浏览器源生支持 mp3,ogg.    mp4 ogv)
   (1) <audio controls src="gm.mp3"></audio>
   (2) 在终端: FFmpeg -i gm.mp3 gm.ogg
   <audio controls>
     <source src="gm.ogg"></source>
     <source src="gm.mp3"></source>
   </audio>

3. 视频

   (1) <video controls src="S8L.mp4"></video>
   (2) 在终端: FFmpeg -i S8L.mp4 S8L.ogg
   <video controls>
     <source src="S8L.ogv"></source>
     <source src="S8L.mp4"></source>
   </video>

4. 麦克风

(async function() {
  let devices = navigator.mediaDevices.enumerateDevices();
  console.log(devices)
  let stream = navigator.mediaDevices.getUserMedia({video: false, audio: true});   // 获取用户的设备
  document.querySelector("audio").srcObject = stream; 
})();