Bug#799262: prospects for Python 3 bindings?

[Arto Bendiken]

For whom it may concern, I just filed a corresponding Ubuntu ticket
(#1556156) for this as well. The description in full:

https://bugs.launchpad.net/debian/+source/opencv/+bug/1556156

Because the packaged OpenCV remains at the obsolete 2.4 release even
still in 16.04 (Xenial Xerus), which is already in feature freeze, it is
looking as though 2018 is the earliest that an Ubuntu LTS release will
package OpenCV 3.x, which at that point will be already some 4 years
old. (And the currently-shipped OpenCV 2.x branch will be going on 9
years.) See bugs #1516985 and #1540168.

This is not a great state of affairs for such an important package, but
what exacerbates the situation is that OpenCV in Ubuntu (and in Debian)
currently altogether lacks Python 3 support. Namely, the current OpenCV
2.4 packages support only Python 2.7, since Python 3 support was
introduced only in OpenCV 3.0 [1], which was only packaged in Debian
(experimental) last December.

This has already been a pain point for OpenCV users (and some packages
requiring OpenCV) and is likely to become a burning problem over the
course of this LTS release's lifecycle. The robotics community (e.g. ROS
users), in particular, rely on Ubuntu LTS as a platform, and are going
to be rather rudely surprised both by Xenial's old OpenCV release and
still more by its lack of Python 3 support.

The relevant upstream Debian bugs are 799262 [2] and 792677 [3]. As
mentioned, OpenCV 3.0 has already been packaged in Debian (packages
libopencv-*3.0) and could be imported to Ubuntu. The Python bindings
(python-opencv) still remain with a Python 2.7 requirement, however,
which needs work upstream.

What can be done here? Would there be any prospect at all for a feature
freeze exception so as to ship OpenCV 3 for Xenial? Once the base
libraries are available, the Python 3 packaging is a much lesser problem
and could even be done via PyPI.

[1] http://opencv.org/opencv-3-0-alpha.html
[2] https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=799262
[3] https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=792677

-- 
Arto Bendiken | @bendiken | http://ar.to