Fuzzy charts on iReport

I am using iReport to insert JFreeChart charts into my report. However,
the text and graphics of the charts ends up looking very fuzzy. I
understand that JFreeChart can produce charts in either .jpg or .png
formats, and I assume that I get fuzzy charts because they're being
saved as .jpgs. Is there a way in iReport I can direct the charts to be
displayed as .pngs instead?

Thanks,

Dane

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