Hi List, JFYI, libpng 1.6.2, which is currently in factory can introduce fails when reading png, namely 'IDAT: invalid distance too far back'. See e. g. multimedia:apps/lilypond build for factory. Very probably, these images will not read anymore with newer libpngs. For multimedia:apps/lilypond example, there are 195 png images, only three fails to read. It is possible to use optipng to fix them or wait for 1.6.3, which will ship png-fix-too-far-back tool (see graphics/libpng17). I am going to create corresponding rpm macro to find and fix these PNGs in a package, where it is called. Again, these PNGs are said to be broken; they should be fixed upstream. If I've understood correctly, not supporting them should help libpng to be more memory-efficient. Further reading & links: https://git.reviewboard.kde.org/r/110314/ Thanks, Petr