function HoverImageButton(obj){
    var path = obj.src.substring(0,obj.src.lastIndexOf("\/") + 1);
    var file = obj.src.substring(obj.src.lastIndexOf("\/") + 1, obj.src.length);
    if(file.lastIndexOf("_hover") == -1){
        file = file.substring(0,file.lastIndexOf("\.")) + "_hover" + file.substring(file.lastIndexOf("\."), file.length);
    }
    else{
        file = file.replace("_hover", "");
    }
    obj.src = path + file;
}