           radius: 15,
                    maxOpacity: 1.,
                    scaleRadius: false,
                    useLocalExtrema: false,
                    latField: 'lat',
                    lngField: 'lng',
                    valueField: 'count',
                    defaultWeight : 1,
                };
                heatmapCfg = $.extend({}, heatmapCfg, options.heatmapOptions || {});
                var layer = new HeatmapOverlay(heatmapCfg);
                L.TimeDimension.Layer.prototype.ini