object-fit-polyfill

<style>

  .object-fit img {
  
    object-fit: cover;
    width: 30%;
    height: 100px;
    
  }

  .object-fit--polyfill {
  
    background-size: cover;
    
  }

  .object-fit--polyfill img {
  
    opacity: 0;
    
  }

</style>

<div class="object-fit">

  <img scr="images.jpg" alt="">

</div>

<script>

if('objectFit' in document.documentElement.style === false)
{
  Array.prototype.forEach.call(document.querySelectorAll('.object-fit'),function(el){

    var image = el.querySelector('img');
    el.style.backgroundImage = 'url("'+image.src+'")';
    el.classList.add('object-fit--polyfill');

  });
}

</script>