text: var BLANK_IMG =
    'data:image/gif;base64,R0lGODlhAQABAAAAACH5BAEKAAEALAAAAAABAAEAAAICTAEAOw=='
  var canvas = document.getElementById('canvas')
    , g = canvas.getContext('2d')
  var ws = new WebSocket('ws://localhost:9002', 'minicap')
  
  ws.binaryType = 'blob'
  
  ws.onclose = function() {
    console.log('onclose', arguments)
  }
  
  ws.onerror = function() {
    console.log('onerror', arguments)
  }
  
  ws.onmessage = function(message) {
    var blob = new Blob([message.data], {type: 'image/jpeg'})
    var URL = window.URL || window.webkitURL
    var img = new Image()
    img.onload = function() {
      console.log(img.width, img.height)
      canvas.width = img.width
      canvas.height = img.height
      g.drawImage(img, 0, 0)
      img.onload = null
      img.src = BLANK_IMG
      img = null
      u = null
      blob = null
    }
    var u = URL.createObjectURL(blob)
    img.src = u
  }
  
  ws.onopen = function() {
    console.log('onopen', arguments)
    ws.send('1920x1080/0')
  }