SOURCE

var canvas = document.getElementById('canvas');
  var editor = new Editor(canvas);

  var videoNode = editor.video("//sf1-ttcdn-tos.pstatp.com/obj/ttfe/video_editor/example2.mp4", {
    crop:{
      cropTop: 100,
      cropBottom: 300,
      cropLeft: 100,
      cropRight: 500
    }
  });
  videoNode.timelineStart(0);
  videoNode.timelineStop(20);
  videoNode.connect(editor.output);

  playButton.onclick = editor.play.bind(editor);
  pauseButton.onclick = editor.pause.bind(editor);
  changeButton.onclick = function(){
    console.log(cropLeft.value, cropRight.value, cropTop.value, cropBottom.value);
    videoNode.crop(cropLeft.value, cropRight.value, cropTop.value, cropBottom.value);
  };
 
  InitVisualisations(editor, 'timeline-canvas', 'current');

<canvas width="640" height="360" id="canvas"></canvas>
  <p>
    <button id="playButton">play</button>
    <button id="pauseButton">pause</button>
  </p>
  <p class="box">
    cropLeft: <input type="text" value="100" id="cropLeft"> cropRight: <input type="text" value="500" id="cropRight"> 
    cropTop: <input type="text" value="100" id="cropTop"> cropBottom: <input type="text" value="300" id="cropBottom"> 
  </p>
  <p>
      <button id="changeButton">change</button>
  </p>
  <p id="current"></p>
  <p>
      <canvas id="timeline-canvas" width="640", height="10"></canvas>
  </p>

html {
  font-family: monospace;
  color: #333;
}
#canvas {
  width: 640px;
  height: 360px;
}
#current {
  font-size: 12px;
}
input {
  width: 50px;
}
button {
  line-height: 1.499;
  position: relative;
  display: inline-block;
  font-weight: 400;
  white-space: nowrap;
  text-align: center;
  background-image: none;
  border: 1px solid transparent;
  cursor: pointer;
  user-select: none;
  height: 32px;
  padding: 0 15px;
  font-size: 14px;
  border-radius: 4px;
  color: rgba(0,0,0,0.65);
  background-color: #fff;
  border-color: #d9d9d9;
  outline: 0;
  transition: all .3s cubic-bezier(.645, .045, .355, 1);
}

button:hover {
  color: #40a9ff;
  background-color: #fff;
  border-color: #40a9ff;
}

.button:active {
  color: #096dd9;
  background-color: #fff;
  border-color: #096dd9;
}
input {
  -webkit-appearance: none;
  background-color: #fff;
  background-image: none;
  border-radius: 4px;
  border: 1px solid #dcdfe6;
  box-sizing: border-box;
  color: #606266;
  display: inline-block;
  font-size: inherit;
  height: 32px;
  line-height: 32px;
  outline: none;
  padding: 0 8px;
  transition: border-color 0.2s cubic-bezier(0.645, 0.045, 0.355, 1);
  width: 50px;
}