Higher Quality of JFreeChart charts

Question

I want to embed a PNG of a chart which I created with JFreeChart into a PDF document. The problem here is, that the quality of the chart is very poor. My goal is to have PNGs with 300 DPI. I googled for almost an hour now but I could not find a solution.

Is there a way to export the generated charts from JFreeCharts as a PNG (or a JPEG) with 300 DPI?

Answer 1

Also take a look at org.jfree.chart.ChartUtilities#writeScaledChartAsPNG

If you provide a scale factor of 2, your chart will be rendered at twice the resolution.

Answer 2

Since version 1.4, JFreeChart uses the png encoder provided by ImageIO. As an alternative , you might look at com.keypoint.PngEncoder, which includes setDpi(), et al. See also org.jfree.chart.encoders.SunPNGEncoderAdapter and org.jfree.chart.encoders.KeypointPNGEncoderAdapter.