foreground image study

HTML

<script src="http://code.highcharts.com/highcharts.js"></script>
<div id="container" style="height: 600px"></div>

JavaScript

$(function () {
    var myImg;
    $('#container').highcharts({
        chart: {
            type: 'column',
            events: {
                load: function () {
                    renderForgroundImage(this);
                },
                redraw: function () {
                    renderForgroundImage(this);
                }
            }
        },
        xAxis: {
            categories: ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec']
        },

        series: [{
            data: [110, 130, 106.4, 129.2, 144.0, 225.0, 135.6, 148.5, 216.4, 194.1, 105.6, 136]
        }]
    }

    );

    function renderForgroundImage(chart) {
        if (myImg) {
            myImg.destroy();
            delete myImg;
        }
        //myImg = chart.renderer.image('http://scanmar.nl/xxxx.png', chart.plotLeft, chart.plotTop, chart.plotWidth, chart.plotHeight)
        myImg = chart.renderer.image('http://i57.tinypic.com/2m2w9iq.png', chart.plotLeft, chart.plotTop, chart.plotWidth, chart.plotHeight)
            .attr({
            'pointer-events': 'none',
            zIndex: 
        })
            .add();

    }
});