Re: Binary descriptors for OpenCV

[Maxim Cournoyer <maxim.cournoyer@gmail.com>]

Hi Ricardo,

Ricardo Wurmus <rekado@elephly.net> writes:

> Hi Guix,
>
> I’d like to draw your attention to https://issues.guix.gnu.org/64945.
> It’s a patch that adds binary descriptors to OpenCV.
>
> These descriptors are the result of a very expensive computation, which
> could be performed with lots of memory and GPUs.  The result is a small
> number of very small descriptors in binary format, which OpenCV can use
> as an input to a feature detection algorithm.
>
> This is probably one of the simplest cases of machine learning output;
> the output is small and compared to other machine learning models
> require only a small amount of computation.  But it’s above the
> threshold for our build farm and not something we can have users
> recompute on install.
>
> The software used to generate these descriptors is freely licensed, and
> the descriptors are living in the twilight zone of assets that are not
> quite software but clearly not just decorative either.  They are large
> arguments to image feature detection algorithms, much like an image mask
> would be.
>
> What shall we do with this patch?  Can we accept it or does it cross a
> line we don’t want to cross?

We should ask what is the FSF's opinion about it, if they have one.  I
personally see trained data models as data more than code; so when their
licensing allows them to be redistributed I see no objection to package
them in Guix.

One example is the 'tesseract-ocr-tessdata-fast' package, which contains
the data of the trained models.  Debian also packages the models of the
different languages as 'tesseract-ocr-eng, 'tesseract-ocr-fra',
etc. [0]; even Parabola offers with its 'tesseract-data-*' packages [1].

[0]  https://packages.debian.org/search?suite=stable&section=all&arch=any&searchon=names&keywords=tesseract
[1]  https://www.parabola.nu/groups/x86_64/tesseract-data/

-- 
Thanks,
Maxim