opencv: rename and default to opencv4

[doronbehar]

Motivation for this change

Make opencv4 the default and make sure all packages that depend on it built with it. The general goal is to reduce closure size for users of packages which can use the latest opencv. See https://discourse.nixos.org/t/nixpkgs-policy-regarding-libraries-available-in-multiple-versions/7026/2

Things done

• Tested using sandboxing (nix.useSandbox on NixOS, or option sandbox in nix.conf on non-NixOS linux)
• Built on platform(s)
  • NixOS
  • macOS
  • other Linux distributions
• Tested via one or more NixOS test(s) if existing and applicable for the change (look inside nixos/tests)
• Tested compilation of all pkgs that depend on this change using nix-shell -p nixpkgs-review --run "nixpkgs-review wip" (used ofborg)
  • faust2jack-unstable (uses opencv2 explicitly now)
  • faust2jaqt-unstable (uses opencv2 explicitly now)
  • Tambura (a dependency of fast2jaqt which hasn't really changed it's inputs)
  • ffmpeg-full
  • frei0r-plugins
  • handbrake
  • hydron-unstable
  • kdenlive
  • liquidsoap-full
  • manim
  • mathematica (uses opencv2 explicitly now (I can't test it since it's unfree))
  • meguca-unstable (already broken)
  • mlt
  • olive-editor
  • libsForQt5.openbr (already broken)
  • openmvs-unstable (already broken)
  • p2pvc (uses opencv2 explicitly now)
  • pfstools (uses opencv2 explicitly now)
  • printrun
  • python2.7-gym
  • python2.7-pydub
  • python2.7-pyglet
  • python2.7-pytmx
  • python2.7-remotecv (already broken)
  • python3.7-baselines
  • python3.7-gym
  • python3.7-moderngl_window
  • python3.7-pydub
  • python3.7-pyglet
  • python3.7-pytmx
  • python3.7-rl-coach (already fails to build on hydra as well)
  • python3.7-roboschool
  • python3.8-gym
  • python3.8-moderngl_window
  • python3.8-pydub
  • python3.8-pyglet
  • python3.8-pytmx
  • python3.8-roboschool
  • retroshare (broken anyway)
  • saga (uses opencv2 explicitly now)
  • seeks (broken anyway)
  • shotcut
  • soundkonverter
  • synfigstudio (already broken)
  • yafaray-core
• Tested execution of all binary files (usually in ./result/bin/)
• Determined the impact on package closure size (by running nix path-info -S before and after)
• Ensured that relevant documentation is up to date
• Fits CONTRIBUTING.md.

[doronbehar]

@GrahamcOfBorg build frei0r

[doronbehar]

@GrahamcOfBorg build handbrake

[doronbehar]

@GrahamcOfBorg build tambura shotcut soundkonverter ffmpeg-full

[doronbehar]

@GrahamcOfBorg build ffmpeg-full

[doronbehar]

@GrahamcOfBorg build retroshare

[doronbehar]

@GrahamcOfBorg build shotcut

[doronbehar]

@GrahamcOfBorg build soundkonverter

[doronbehar]

@GrahamcOfBorg build synfigstudio

[doronbehar]

@GrahamcOfBorg build saga

[doronbehar]

@GrahamcOfBorg build kdenlive

[doronbehar]

@GrahamcOfBorg build manim

[doronbehar]

@GrahamcOfBorg build mlt

[doronbehar]

@GrahamcOfBorg build hydron

[doronbehar]

@GrahamcOfBorg build meguca

[doronbehar]

@GrahamcOfBorg build libsForQt5.openbr

[doronbehar]

@GrahamcOfBorg build liquidsoap

[doronbehar]

@GrahamcOfBorg build printrun

[doronbehar]

@GrahamcOfBorg build pfstools

[doronbehar]

@GrahamcOfBorg build openmvs

[doronbehar]

@GrahamcOfBorg build p2pvc

[doronbehar]

@GrahamcOfBorg build olive-editor

[doronbehar]

@GrahamcOfBorg build python2Packages.gym python37Packages.gym python38Packages.gym

@GrahamcOfBorg build python2Packages.pydub python37Packages.pydub python38Packages.pydub

@GrahamcOfBorg build python2Packages.pyglet python37Packages.pyglet python38Packages.pyglet

[doronbehar]

@GrahamcOfBorg build python2Packages.pytmx python37Packages.pytmx python38Packages.pytmx

@GrahamcOfBorg build python2Packages.remotecv python37Packages.remotecv python38Packages.remotecv

@GrahamcOfBorg build python37Packages.baselines

@GrahamcOfBorg build python37Packages.rl-coach python38Packages.rl-coach

@GrahamcOfBorg build python37Packages.roboschool python38Packages.roboschool

[doronbehar]

@GrahamcOfBorg build python37Packages.moderngl-window

[doronbehar]

To make the checks visible after all the fixes have been commited, I'm executing all of the builds here once more:

@GrahamcOfBorg build frei0r
@GrahamcOfBorg build handbrake
@GrahamcOfBorg build tambura shotcut soundkonverter ffmpeg-full
@GrahamcOfBorg build ffmpeg-full
@GrahamcOfBorg build retroshare
@GrahamcOfBorg build shotcut
@GrahamcOfBorg build soundkonverter
@GrahamcOfBorg build synfigstudio
@GrahamcOfBorg build saga
@GrahamcOfBorg build kdenlive
@GrahamcOfBorg build manim
@GrahamcOfBorg build mlt
@GrahamcOfBorg build hydron
@GrahamcOfBorg build meguca
@GrahamcOfBorg build libsForQt5.openbr
@GrahamcOfBorg build liquidsoap
@GrahamcOfBorg build printrun
@GrahamcOfBorg build pfstools
@GrahamcOfBorg build openmvs
@GrahamcOfBorg build p2pvc
@GrahamcOfBorg build olive-editor
@GrahamcOfBorg build python2Packages.gym python37Packages.gym python38Packages.gym
@GrahamcOfBorg build python2Packages.pydub python37Packages.pydub python38Packages.pydub
@GrahamcOfBorg build python2Packages.pyglet python37Packages.pyglet python38Packages.pyglet
@GrahamcOfBorg build python2Packages.pytmx python37Packages.pytmx python38Packages.pytmx
@GrahamcOfBorg build python2Packages.remotecv python37Packages.remotecv python38Packages.remotecv
@GrahamcOfBorg build python37Packages.baselines
GrahamcOfBorg build python37Packages.rl-coach python38Packages.rl-coach (broken but not marked as so)
@GrahamcOfBorg build python37Packages.roboschool python38Packages.roboschool
@GrahamcOfBorg build python37Packages.moderngl-window

[doronbehar]

@Mic92 I made opencv4 the default opencv and thoroughly tested all of the affected packages with ofborg's help. Some of the affected packages were marked as broken already, and some of them do compile only with opencv2, hence the other commits.

All of the checks are available here: https://github.com/NixOS/nixpkgs/pull/86808/checks

[Mic92]

Thanks a lot for your work!
In separate PR it might be also worth looking at what opencv3 usages can be upgraded to opencv4.

[flokli]

Thanks for this!