Issue in qqfileuploader


I have a issue in qqfileuploader. When i am trying to upload image then get error:

NetworkError: 500 Internal Server Error

I am using below code…I already set csrf token in request but still get error…
**function createUploader(){
var uploader = new qq.FileUploader({
element: document.getElementById(‘file-uploader’),
action: ‘uploadimage’,
params: {
authenticity_token: $(‘meta[name=csrf-token]’).attr(‘content’)
allowedExtensions: [‘png’, ‘gif’, ‘jpg’, ‘jpeg’],
multiple: false

// in your app create uploader as soon as the DOM is ready
// don't wait for the window to load 
window.onload = createUploader;**

If any have a solutions then please send me asap.