Untitled

<!DOCTYPE html>
<html lang="es">
<head>

<link rel="stylesheet" href="css/miestilos.css">
<script
  src="https://ajax.googleapis.com/ajax/libs/jquery/1.12.4/jquery.min.js">
</script>
</head>
<body>
<div>
    <input type="file" id="files"  />
    <output id="list"></output>
</div>
<div id="altura">Altura</div>
<div id="anchura">Anchura</div>

<script type="text/javascript" src= "js/app.js"></script>

</body>
</html>

$(document).ready(function() {
 function handleFileSelect(evt) {
 var files = evt.target.files; // FileList object

 // Loop through the FileList and render image files as thumbnails.
 for (var i = 0, f; f = files[i]; i++) {

  // Only process image files.
  if (!f.type.match('image.*')) {
    continue;
  }

  var reader = new FileReader();

  // Closure to capture the file information.
  reader.onload = (function(theFile) {
    return function(e) {
      // Render thumbnail.
      var span = document.createElement('span');
      document.getElementById('list').innerHTML='';
      span.innerHTML = ['<img class="center" id="imagen" src="', e.target.result,
                        '" title="', escape(theFile.name), '"/>'].join('');


      document.getElementById('list').insertBefore(span, null);
            };

  })(f);


  // Read in the image file as a data URL.
  reader.readAsDataURL(f);
 }
}

document.getElementById('files').addEventListener('change', handleFileSelect, false);


 });