Saving a plot in Octave with a transparent background

Question

I've plotted some GPS tracks and heading vectors using Octave.

I'd like to overlay the plot on a satellite image, but when I save the plot it has a white background. Is there a way to save it with a transparent background?

Answer 1

I think using print with the "pngalpha" device does what you want, e.g.:

print(gcf,'-dpngalpha', 'myplot.png');

This is poorly documented unfortunately. I browsed the source code extensively to find a way to hack/patch octave to do this, only to find out this was already possible.