If you draw a circle in Libre Office Draw, you get a perfect circle. However, if you export it with "File -> Export..." and export it as a "Selection" and save it as a .png or .gif picture the right and bottom part of the circle are not round any more. See the picture below.
What can be done about this? Is there a work-around available?
Inkscape worked for me. Export as vector SVG from LibreOffice, then open in Inkscape and export as raster PNG file. Here is my circle:
The recommendation is from https://stackoverflow.com/a/33726722/5100564. I used the Inkscape GUI rather than the command line commands suggested in the answer.