JavaScript-Load-Image afte Crop add to jQuery-File-Upload

Question

JavaScript Load Image Demo Can I add result from crop to file upload ? jQuery File Upload Demo

 file.canvas = $j('#result canvas');
 file.type = 'blob';

 $('#fileupload').fileupload('add', {files: file});

Not work

$('#fileupload').fileupload('add', {files: $j('#result a').attr('href')});

Not work