[bug#30801] [PATCH 0/1] Add opencv

[ludo@gnu.org (Ludovic Courtès)]

Hello Björn,

Björn Höfling <bjoern.hoefling@bjoernhoefling.de> skribis:

> On Thu, 15 Mar 2018 22:04:54 +0100
> ludo@gnu.org (Ludovic Courtès) wrote:
>
>> Hi Björn,
>> 
>> Björn Höfling <bjoern.hoefling@bjoernhoefling.de> skribis:
>> 
>> > The test suite consists of an extra package, weighting 465MB
>> > compressed. It runs very well. I think the size is worth it. It
>> > consists of proprietary things (i.e. lena.jpg). As far as I
>> > understand, that is OK, if it doesn't get in the final src/bin
>> > store output. Right?  
>> 
>> As a rule of thumb, there should not be non-free stuff in the
>> derivation graph.
>> 
>> If there’s non-free software, that’s not OK, even if it doesn’t show
>> up in the output.
>> 
>> If it’s “just” data (pictures) that are non-free, that’s OK per the
>> FSDG:
>> <https://www.gnu.org/distros/free-system-distribution-guidelines.html#non-functional-data>.
>> If we could replace it with a free variant, I think we should clearly
>> encourage it, but lena.jpg is hardly replaceable in this context (I’d
>> hope it weren’t around for what it tells about CS, but that’s another
>> story…).
>
> What is being downloaded is in the store of cause, but it is only
> images and videos, no code. And it is not linked against.
>
> The suite is 400 MB in size and replacing Lena with Linus or even
> better pictures and videos of trees would need a fundamental idea of
> the algorithms behind OpenCV, with I don't have. So for now I just leave
> it as is, though I agree with your fundamental ideas :-)

OK, sounds good.

> Most are 50MB, one is 265MB, I suppose that was the latest with all
> dependencies and all (free) OpenCV modules. So the 1.1GB was
> definitively the convex hull including all dependencies.
>
> The whole thing is more or less only "lib".
>
> I forgot to mention that I ignored the "doc" package: It built one when
> I added doxygen as a dependency, but it did not install it. Now that I
> know how to manually copy/install files, I could give that another try.
> But that would add (to a :doc output, of cause), not substract.
>
> The "bin" part is only 7 MB, so not worth mentioning. There are some
> examples which I did not include, because they are not very interesting
> in the compiled version, but more for understanding the programming
> part from the source code.

OK.

> OK, I looked into some other packages and tried to split it into pieces
> (one piece for now). What I do is just add a phase after install and
> copy things manually (copied from the git package definition):
>
> +       (add-after 'install 'split
> +         (lambda* (#:key outputs #:allow-other-keys)
> +           (let* ((outputs-out (assoc-ref outputs "out"))
> +                  (outputs-feature2d (assoc-ref outputs "feature2d"))
> +                  (outputs-face  (assoc-ref outputs "face"))
> +                  (outputs-core (assoc-ref outputs "core"))
> +                  (libface     (string-append outputs-out "/lib/libopencv_face.so"))
> +                  (libface*    (string-append outputs-face "/lib/libopencv_face.so"))
> +                  (libface3.4     (string-append outputs-out "/lib/libopencv_face.so.3.4"))
> +                  (libface3.4*    (string-append outputs-face "/lib/libopencv_face.so.3.4"))
> +                  (libface3.4.1     (string-append outputs-out "/lib/libopencv_face.so.3.4.1"))
> +                  (libface3.4.1*    (string-append outputs-face "/lib/libopencv_face.so.3.4.1")))
> +
> +                  
> +                  (mkdir-p (string-append outputs-face "/lib"))
> +                  
> +                  (for-each (lambda (old new)
> +                              (copy-file old new)
> +                              (delete-file old)
> +                              (chmod new #o555))
> +                            (list libface libface3.4 libface3.4.1)
> +                            (list libface* libface3.4* libface3.4.1*))
> +                  )
> +           #t ; TODO: Implement it.
> +           ))
> +       )))
>
> The problem here is that this doesn't correct the RPATHS and I will get
> problems with dependent library parts (The python modules in that case):
>
> phase `strip' succeeded after 0.5 seconds
> starting phase `validate-runpath'
> validating RUNPATH of 46 binaries in "/gnu/store/f7aqk1my2bdprhgp3gxmnl9227gxf43m-opencv-3.4.1/lib"...
> /gnu/store/f7aqk1my2bdprhgp3gxmnl9227gxf43m-opencv-3.4.1/lib/python3.6/site-packages/cv2.cpython-36m-x86_64-linux-gnu.so: error: depends on 'libopencv_face.so.3.4', which cannot be found in RUNPATH ("/gnu/store/f7aqk1my2bdprhgp3gxmnl9227gxf43m-opencv-3.4.1/lib" "/gnu/store/124ymrzp0dwx6qfh4r4r4763sa5k48sv-libsm-1.2.2/lib" "/gnu/store/dbdjmralkrzqn6b093hp69bjljvfr7zm-libice-1.0.9/lib" "/gnu/store/g7sak8qzk7lk06ggn38xpfv5mb8da6kk-libxt-1.1.5/lib" "/gnu/store/n6acaivs0jwiwpidjr551dhdni5kgpcr-glibc-2.26.105-g0890d5379c/lib" "/gnu/store/xfjba1kww8ngdc6nxldd8ly93nh13ayy-gcc-5.5.0-lib/lib" "/gnu/store/xfjba1kww8ngdc6nxldd8ly93nh13ayy-gcc-5.5.0-lib/lib/gcc/x86_64-unknown-linux-gnu/5.5.0/../../..")

Right, you cannot just move .so files after the fact because
cv2.cpython-36m-x86_64-linux-gnu.so, for instance, has …/lib in its
RUNPATH, not …-lib/lib.  If you wanted to do that, the right way to do
it would be by modifying the makefiles/cmakelists so that they
explicitly install libopencv_face to …-lib/lib.

That said, it may be safer/easier to keep all libraries in the same
output.

BTW, are .a files installed?  It would probably help save space to not
install them.

Thanks for the update & have a nice week-end!

Ludo’.