Hi Stuart, On 03.06.2015 11:14, Stuart Prescott wrote: >> 1: https://wiki.debian.org/Debate/libav-provider/ffmpeg > > thanks for this -- it's good to see a summary of where we are. > > It would be good if you also include information on:
Thanks for the feedback. > * the API stability promise of upstream (do we need a library transition > each time a minor update is uploaded?) No API/ABI should ever change with bugfix releases, i.e. 2.6.* releases all have the same. With most new major upstream releases 2.* only new API is introduced and private API/ABI changed. So only buggy programs that use private API need to be fixed (see e.g. #783879 [1]). With some new major upstream releases the soversions get increased, at which point we need a library transition. > * assuming there is an API stability promise within each branch, the > frequency at which new releases are made that will require transitions The upstream tracker [2] gives a good overview about this. The last soversion bumps were: * 2.4 (2014-09-14) * 2.2 (2014-03-24, only libavfilter) * 2.0 (2013-07-10) * 1.1 (2013-01-07) * 1.0 (2012-09-28, only libavfilter) So transitions would be about once every half year and if one doesn't count libavfilter, because it only has a handful of reverse-dependencies, it's more like once per year. > * the detailed plan on how Debian would get from the current packages to > these packages. > > The libav→ffmpeg plan is in various places on this and the debian-release > mailing lists, but it would be good to see it in one place for easy > reference. I think the most relevant mail is [3]. > I think we need to see a good overview of: > > - what source and binary package names will be uploaded to which releases There are three source packages, whose binaries should be changed to: * src:ffmpeg: - ffmpeg, ffmpeg-doc, ffmpeg-dbg, qt-faststart - lib*-ffmpegN - lib*-dev - lib*-ffmpeg-dev (transitional, to be removed before stretch release) - libav-tools-links (transitional, to be removed after stretch release) * src:libav: - libav-tools, libav-doc, libav-dbg - lib*N - libavcodec-extra* - lib*-libav-dev * src:libpostproc: - libpostproc52 - libpostproc-libav-dev I have patches implementing these changes, which I plan to send to the BTS soon. The uploads will first go to experimental and after passing NEW and getting a transition slot from the release team, to unstable. > - which binary packages would disappear (and what to do about that) Short term: none For stretch: everything still built from src:libav and src:libpostproc and lib*-ffmpeg-dev. What we'll do about that is the library transition and what's mentioned in the point below. > - what will be required from maintainers of rdeps Most will have to do nothing special, only those mentioned in above mail [3] need to adapt their packages, e.g. change dependencies on libav-tools to ffmpeg (list in [3]) and drop dependencies on libavcodec-extra (from devede and dvd-slideshow). > - what sort of time periods the transition would take Well, the actual library transition will probably take about 5 days, which is the time after which britney propagates the binNMUs to testing. When it will happen depends on how long NEW processing will take and when a suitable transition slot is available. Changing the dependencies/recommends/suggests from libav-tools to ffmpeg should be done before stretch is released. > - the results of the rebuilds you have done These are available in above mail [3]. blender, mpd and paraview are resolved in the meantime. > - (I'd guess a ben file for the transition tracker would be handy too) I think the following should work: title = "ffmpeg"; is_affected = .depends ~ "libavcodec56|libavcodec-extra-56|libavdevice55|libavfilter5|libavformat56|libavresample2|libavutil54|libpostproc52|libswscale3" | .depends ~ "libavcodec-ffmpeg56|libavdevice-ffmpeg56|libavfilter-ffmpeg5|libavformat-ffmpeg56|libavresample-ffmpeg2|libavutil-ffmpeg54|libpostproc-ffmpeg53|libswresample-ffmpeg1|libswscale-ffmpeg3"; is_good = .depends ~ "libavcodec-ffmpeg56|libavdevice-ffmpeg56|libavfilter-ffmpeg5|libavformat-ffmpeg56|libavresample-ffmpeg2|libavutil-ffmpeg54|libpostproc-ffmpeg53|libswresample-ffmpeg1|libswscale-ffmpeg3"; is_bad = .depends ~ "libavcodec56|libavcodec-extra-56|libavdevice55|libavfilter5|libavformat56|libavresample2|libavutil54|libpostproc52|libswscale3"; > I'm aware that the plan is somewhat orthogonal to the actual decision about > libav providers but I think the feasibility of the plan also informs us > about the feasibility of making the change and gives confidence that the > ffmpeg maintainers are aware of the size of the task they are volunteering > for. OK, so I'll try to put this information on the Wiki. Best regards, Andreas 1: https://bugs.debian.org/783879 2: http://upstream-tracker.org/versions/ffmpeg.html 3: https://lists.alioth.debian.org/pipermail/pkg-multimedia-maintainers/2015-May/043980.html _______________________________________________ pkg-multimedia-maintainers mailing list pkg-multimedia-maintainers@lists.alioth.debian.org http://lists.alioth.debian.org/cgi-bin/mailman/listinfo/pkg-multimedia-maintainers
