Hi Andrzej, I did not find a simple way to predict the bit stream length without repeating lots of code lines. On the other hand, I also did not see an effect on the run time, so the simple iteration looked good enough to me. If you find different results, I'll try again. In the meantime I was working on other improvements in the existing filters, found some more special cases which can be improved, but the effect will probably be smaller. Gerd ________________________________ Von: mkgmap-dev <mkgmap-dev-bounces@lists.mkgmap.org.uk> im Auftrag von Andrzej Popowski <popej@poczta.onet.pl> Gesendet: Dienstag, 19. Juli 2016 13:09:15 An: mkgmap-dev@lists.mkgmap.org.uk Betreff: Re: [mkgmap-dev] [Patch v1] improve LinePreparer to reduce img size Hi Gerd, this is great improvement, thanks! I have tested your patch on a road map and get about 4% decrease of map size. I'm compiling topo map now, I think it is over 10% size reduction. I would like to suggest some optimizing of code. I think, you can get optimum bit length directly in procedure calcDeltas from LinePreparer. Just instead of only looking for min/max bit length, create full profile: number of legs vs bit length, so you can estimate full bit size like you have done it in your previous posts, without actually processing a line. I hope this makes sens, I don't know your code so well. -- Best regards, Andrzej _______________________________________________ mkgmap-dev mailing list mkgmap-dev@lists.mkgmap.org.uk http://www.mkgmap.org.uk/mailman/listinfo/mkgmap-dev