BaseChart.setBgImage

Uses the image from the specified file or resource as the background image of the chart.

Argument	Default	Description
filename	(Mandatory)	The pathname of the image file or resource, which must be of PNG, JPG or GIF format. Please refer to Path Specification on how ChartDirector interprets pathnames.
align	Center	The alignment of the background image relative to the chart. See Alignment Specification for supported alignment types.