I’m running Ubuntu 14.04.2 x64 but I don’t think that has anything to do with it, just felt it would be good to know.
When I insert an image into my document it looks poor, with jagged edges, even in print preview, but the final output in PDF is good. One can tell the rendering quality has been reduced by default.
Applications like InDesign or Scribus have a performance setting where one can adjust the rendering quality of images.
Is there something similar in LibreOffice?
Thanks for the details in your question! I was worried when I imported a PDF as picture and the rendering did not look good. However, I decided to try because you mentioned the final output is good, and indeed It is even better than I thought!
Although I manipulated the PDF as an image, the output was still text based and the text could be selected. Really really impressive!
Try going up to the Libre menu, select Tools/Options, under the first category on the left (LibreOffice) select Memory, then look at the Graphics Cache section. Try the following settings then experiment if not working for you.
Use for LibreOffice 128 MB
Memory per object 20 MB