Exporting chart to image - scaled

HTML

<script type="text/javascript" src="http://www.amcharts.com/lib/3/amcharts.js"></script>
<script type="text/javascript" src="http://www.amcharts.com/lib/3/exporting/amexport_combined.js"></script>
<script type="text/javascript" src="http://www.amcharts.com/lib/3/serial.js"></script>
<script type="text/javascript" src="http://www.amcharts.com/lib/3/themes/none.js"></script>
<div id="chartdiv"></div>

CSS

#chartdiv {
    width : 100%;
    height : 500px;
}

JavaScript

var chart;

var chartData = [{
   "country": "USA",
       "visits": 4025,
       "color": "#FF0F00"
}, {
   "country": "China",
       "visits": 1882,
       "color": "#FF6600"
}, {
   "country": "Japan",
       "visits": 1809,
       "color": "#FF9E01"
}, {
   "country": "Germany",
       "visits": 1322,
       "color": "#FCD202"
}, {
   "country": "UK",
       "visits": 1122,
       "color": "#F8FF01"
}, {
   "country": "France",
       "visits": 1114,
       "color": "#B0DE09"
}, {
   "country": "India",
       "visits": 984,
       "color": "#04D215"
}, {
   "country": "Spain",
       "visits": 711,
       "color": "#0D8ECF"
}, {
   "country": "Netherlands",
       "visits": 665,
       "color": "#0D52D1"
}, {
   "country": "Russia",
       "visits": 580,
       "color": "#2A0CD0"
}, {
   "country": "South Korea",
       "visits": 443,
       "color": "#8A0CCF"
}, {
   "country": "Canada",
       "visits": 441,
       "color": "#CD0D74"
}, {
   "country": "Brazil",
       "visits": 395,
       "color": "#754DEB"
}, {
   "country": "Italy",
       "visits": 386,
       "color": "#DDDDDD"
}, {
   "country": "Australia",
       "visits": 384,
       "color": "#999999"
}, {
   "country": "Taiwan",
       "visits": 338,
       "color": "#333333"
}, {
   "country": "Poland",
       "visits": 328,
       "color": "#000000"
}];


var chart = AmCharts.makeChart("chartdiv", {
   "theme": "none",
   type: "serial",
   dataProvider: chartData,
   categoryField: "country",
   depth3D: 20,
   angle: 30,

   categoryAxis: {
       labelRotation: 90,
       gridPosition: "start"
   },

   valueAxes: [{
       title: "Visitors"
   }],

   graphs: [{

       valueField: "visits",
       colorField: "color",
       type: "column",
       lineAlpha: 0.1,
       fillAlphas: 1
   }],

   chartCursor: {
       cursorAlpha: 0,
       zoomable: false,
       categoryBalloonEnabled: false
   },
   pathToImages: "http://www.amcharts.com/lib/3/images/",
   exportConfig: {
      ...