Using the old SWIG Python interface to OpenCV instead of the new one?

[Vitorio Miliano]

Hi,

I noticed that even though you're developing on Lucid, which includes OpenCV 2.x and the matching Python bindings, you're using the old (deprecated) SWIG bindings from 1.x instead.

http://stackoverflow.com/questions/1650568/how-do-i-create-an-opencv-image-from-a-pil-image describes the differences.

http://opencv.willowgarage.com/documentation/python/introduction.html is the new interface.

Is there a reason for this?

(It may be worth noting that Lucid's version of the (deprecated) NumPy2PIL function makes those tests pass on Jaunty, so it's probably an OpenCV issue in that particular case.)

[Gustavo Niemeyer (niemeyer)]

No, not great reason really. I'm using only three or four functions from OpenCV at this point, and I bet we can make it work with either version. I really wish that pyopencv was more widely adopted, though, since it seems to support a lot more of OpenCV's functinality, but that's an unrelated rambling.

Do you want to give that change a try?

If not, I'll try to have a quick look at it in the next few days.

[Gustavo Niemeyer (niemeyer)]

Sorry, if it's not clear, I meat using the new interface of OpenCV, not pyopencv.

[Gustavo Niemeyer (niemeyer)]

*meant*

[Ara Pulido (ara)]

Take into account that, although Lucid includes OpenCV 2.0, the python bindings in Lucid are for 1.x.
There is a PPA for Lucid for the new bindings:
http://gijs.pythonic.nl/blog/2010/apr/1/ubuntu-opencv-20-and-new-python-api/

[Tony Simpson (agjasimpson)]

I looked at all the opencv wrappers available last night and decided ctypes-opencv was the best choice on windows, its available on pypi and supports 2.x and 3.x + has some very nice helper methods (like as_numpy_array on image). Seems to cover most of opencv. Didn't work out of the box with the current opencv windows download but fixing that was easy.

[Gustavo Niemeyer (niemeyer)]

Ara, ah, that explains it, thanks.

Tony, agreed. I also found out that pyopencv seems to be the best bindings available, both in interface and in the range of the API supported, but I found it somewhat tricky to compile it against recent versions of opencv/etc. A couple of weeks ago I filed a few bugs in the tracker and have been talking to the author.