resizeImage.js

function resizeImage(el, width, height, quality) {
  var canvas = document.createElement('canvas')
  canvas.width = width
  canvas.height = height
  var context = canvas.getContext('2d')
  context.drawImage(el, 0, 0, width, height)
  
  try {
    return canvas.toDataURL('image/jpeg', quality)
  } catch (e) {
    return null
  }
}