Yes
(but not permanently)
That's the answer. More specific what you have to do:
Let the user select the file via a form input="file", read the file via JavaScript and output the blob on the site.
Here's a good tutorial: http://www.html5rocks.com/en/tutorials/file/dndfiles/
The main code they are using:
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');
          span.innerHTML = ['<img class="thumb" 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);