FileUpload with FormData

gistfile1.js

var data = new FormData();
data.append('videoshow[title]', 'FormData');
data.append('videoshow[logo]', $('#videoshow_logo')[0].files[0]);

var xhr = $.ajax({
  url: '/admin/videoshows',
  dataType : 'script',
  contentType: false,
  cache: false,
  processData: false,
  type: 'POST',
  data: data
});