Validate and remove files that exceed the maximum file size:

				upload.bind('FilesAdded', function(up, files) {
					//console.log(files);
					var max_size = 1024*1024*1;//1MB
					for(var i = 0; i < files.length; i++){
						var f = files[i];
						if(f.size > max_size){
							alert(f.name + ' exceed the maximum size');
							up.splice(i, 1);
						}
					}
				});

 

Reference:

1. Official: http://www.plupload.com
2. http://www.gemingcao.com/archives/plupload-duowenjianshangchuan.html