How to use opencv with python on macos

Question

I am porting a python+opencv app developped on windows to mac.

On windows i have the cv2.pyd in my virtualenv site-packages and it goes well.

I am new to mac and I don't understand hot it should work. I didn't find any binaries for opencv python bindings and it seems that the rightway is to use macport.

macport is copying the cv.py and cv2.so in the opts/.../site-packages.

At this point how to use it?

I tried to copy manually these two files but I am getting an error

>>> import cv
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/cv.py", line 1, in <module>
    from cv2.cv import *
ImportError: dlopen(/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/cv2.so, 2): no suitable image found.  Did find:
        /Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/cv2.so: mach-o, but wrong architecture

What's wrong?

Update: As asked by @Vortexfive:

$ file /Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/cv2.so
/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/cv2.so: Mach-O 64-bit dynamically linked shared library x86_64

$ file /Library/Frameworks/Python.framework/Versions/2.6/bin/python
/Library/Frameworks/Python.framework/Versions/2.6/bin/python: Mach-O universal binary with 2 architectures
/Library/Frameworks/Python.framework/Versions/2.6/bin/python (for architecture ppc):    Mach-O executable ppc
/Library/Frameworks/Python.framework/Versions/2.6/bin/python (for architecture i386):   Mach-O executable i386

It seems there is a mismatch. How to fix it?

Can you give the output of 'file /Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/cv2.so' and 'file which python'. This sounds like a mismatch of the target architectures (i386,x86_64). — kheyse
– kheyse, Commented Oct 26, 2012 at 9:25

kheyse · Accepted Answer · 2012-10-26 13:26:39Z

1

It seems there's a mismatch in target architectures. You can try to install opencv in macports with the +universal variant.

Another option is to update your version of Python. Newer versions are compiled for x86_64 too I believe.

As a third alternative you can install opencv with the +python27 in macports. You can then select the macports version of Python by doing sudo port select python27.

edited Oct 26, 2012 at 13:26

answered Oct 26, 2012 at 12:15

kheyse

1,91913 silver badges20 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

Nianliang · Accepted Answer · 2013-07-21 01:53:46Z

1

In my case, which the arch is matched:

$ file ../../release.mac/lib/cv2.so 
../../release.mac/lib/cv2.so: Mach-O 64-bit dynamically linked shared library x86_64
$ file `which python`
/usr/bin/python: Mach-O universal binary with 2 architectures
/usr/bin/python (for architecture x86_64):  Mach-O 64-bit executable x86_64
/usr/bin/python (for architecture i386):    Mach-O executable i386

But not aware that the python run in 32 bit mode:

$ defaults read com.apple.versioner.python Prefer-32-Bit
1

Fixed by:

$ VERSIONER_PYTHON_PREFER_32_BIT=0 python

or

$ defaults write com.apple.versioner.python Prefer-32-Bit -bool no

answered Jul 21, 2013 at 1:53

Nianliang

3,1063 gold badges31 silver badges23 bronze badges

Collectives™ on Stack Overflow

How to use opencv with python on macos

2 Answers 2

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related