#38730: octave-devel @3.6.3 GraphicsMagick limits images to 8 bits per pixel ---------------------------+-------------------------------- Reporter: cwr@… | Owner: macports-tickets@… Type: defect | Status: new Priority: Normal | Milestone: Component: ports | Version: 2.1.3 Resolution: | Keywords: Port: octave-devel | ---------------------------+-------------------------------- Comment (by ryandesign@…): ImageMagick, from which GraphicsMagick was forked some years ago, also supports these pixel quantum sizes, but its default is 16 bits. The ImageMagick libraries build differently depending on the pixel quantum depth, and therefore so do any programs that link against those libraries. This causes problems, as I discussed with the ImageMagick developers [http://www.imagemagick.org/discourse- server/viewtopic.php?f=2&t=22932&p=95966 here]. Consider that our buildbot builds ports with the default variants, so ImageMagick on the buildbot was built with q16. And therefore any other ports that link with ImageMagick libraries were built on the buildbot linked with q16 ImageMagick libraries. Now imagine a user installs ImageMagick q8. Since that's not the default variant, there's no binary for it on our server, so it builds from source on the user's system. Next, the user installs some program X that uses ImageMagick libraries. Ports that use ImageMagick don't have q8, q16 and q32 variants; they just assume ImageMagick is ImageMagick. So the user could receive a binary of X that was built on the buildbot using q16, and that program will now behave incorrectly because it was built for q16 libraries but is now running with q8 libraries. Therefore, in the next [ticket:38134 ImageMagick port update], I will remove the possibility to select the pixel quantum depth and always use the default of 16. The alternative is to completely redesign the ImageMagick port, including splitting it into subports for each pixel quantum depth and revising the dependencies of every port using ImageMagick. I thought about doing this, but it's so much work. Another possible solution is to add q8, q16 and q32 variants to every port that uses ImageMagick libraries, but that's a mess too. I do not yet know if the GraphicsMagick libraries also vary depending on pixel quantum depth but I assume they do. If they do, they're affected by the same problem, so I should remove the possibility to change the pixel quantum size from the GraphicsMagick port as well. -- Ticket URL: <https://trac.macports.org/ticket/38730#comment:4> MacPorts <http://www.macports.org/> Ports system for OS X