Hi, On Tue, Oct 3, 2017 at 7:17 PM, Elle Stone <ellestone@xxxxxxxxxxxxxxxxxxxx> wrote: > I was curious about the disparity in reported size between the size on disk > in a file manager, and the size reported by "%m". I'm guessing "%m" is the > size in memory? > > For example, I have a GIMP 2.9 XCF that is 4000 x 6000 pixels, 7 layers. > It's the early stages of a drawing, with very little information on the > various layers, just the main outlines, some guidelines and a merged layer > in shades of gray. > > The size of the XCF file on disk is 11.5 MiB as measured by the Dolphin file > manager. When I open the XCF file in GIMP, the size shown in the status bar > is 3.8 GB. I don't know how this info is computed in GIMP code (i.e. does it check for actual memory size or does it do some basic maths as I am about to do), but assuming your image is 8 bits per channel, and all 7 layers are the size of the image and have no alpha, that makes: 4000*6000*7*24 = 4 032 000 000 / 1024^3 ~ 3.8GB! :-) > Why such a huge difference in reported size? Basically in memory, we don't compress. It doesn't matter if your image were even full unicolor (which could compress perfectly and could result in a file of a few bytes in any compressed format even if the image was billions of pixels). As such, every bytes is fully repeated in memory, even if it were the same. Jehan > _______________________________________________ > gimp-developer-list mailing list > List address: gimp-developer-list@xxxxxxxxx > List membership: https://mail.gnome.org/mailman/listinfo/gimp-developer-list > List archives: https://mail.gnome.org/archives/gimp-developer-list -- ZeMarmot open animation film http://film.zemarmot.net Patreon: https://patreon.com/zemarmot Tipeee: https://www.tipeee.com/zemarmot _______________________________________________ gimp-developer-list mailing list List address: gimp-developer-list@xxxxxxxxx List membership: https://mail.gnome.org/mailman/listinfo/gimp-developer-list List archives: https://mail.gnome.org/archives/gimp-developer-list
