Php Dropzone-resizeWidth、resizeHeight不起作用

我正在我的网站上使用dropzone。其他一切都很好，但只要我添加resizeWidth或resizeHeight，它就会崩溃。下面是我正在使用的脚本。请注意，只要我删除“调整大小”选项，它就可以正常工作。请参见下面我正在使用的脚本。 你能提出可能的问题吗

var previewNode = document.querySelector("#template");
previewNode.id = "";
var previewTemplate = previewNode.parentNode.innerHTML;
previewNode.parentNode.removeChild(previewNode);

      $('#dropArea').dropzone({
    url:  'dzimgupload.php',
    thumbnailWidth: null,
    thumbnailHeight: null,
    maxFilesize: 0.5,
    uploadMultiple: false,
    autoProcessQueue: false,
    addRemoveLinks: true,
    acceptedFiles: "image/*" ,
    maxFiles:  1,
    resizeHeight: 800,
    dictDefaultMessage: "Choose or drop  Image from your computer",
    dictFileTooBig: "File is too big and won't be uploaded. Filesize:{{filesize}}MB. Max filesize: {{maxFilesize}}MB.",
    previewTemplate: previewTemplate,


    init:       function(){
        dzClosure = this;
        this.on("thumbnail", function(file, url) {
                $('.dz-image').last().find('img').attr({width: '100%', height: '100%'});
            }),
        $('.dzsubmit').on('click',function(e) {
            dzClosure.processQueue(); /* My button isn't a submit */
        });


        this.on("maxfilesexceeded", function(file) {
            this.removeAllFiles();
            this.addFile(file);
      });
    },


});