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importing PIL into a rosnode

asked 2011-04-22 09:10:18 -0500

jrieffel gravatar image

updated 2014-01-28 17:09:34 -0500

ngrennan gravatar image

when I have the line

"from PIL import Image"

in a node, I get the following error when running my node via rosrun

"ImportError: No module named PIL"

of course, PIL is installed in


but is not an ROS library. How can I change my manifest.xml to find PIL? If I understand correctly, rosrun clobbers my existing PYTHONPATH (when running python I can import PIL just fine).

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answered 2011-04-25 05:26:26 -0500

jrieffel gravatar image

I resolved it by explicitly putting PIL in my .bashrc's PYTHONPATH

oddly, however, python from the command line runs python 2.6.6, but rosrun on a python node somehow invokes python 2.6.1

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answered 2011-04-23 06:26:48 -0500

kwc gravatar image

This sounds like an issue with a MacPorts setup. On OS X, it is often necessary to run the python_select tool to use the version of Python managed by MacPorts instead.

The simplest test of your setup is:

$ python
>>> import PIL

rosrun does not alter your PYTHONPATH, and there are no modifications necessary in ROS to use a system-installed Python library. rosrun is nothing more than a convenience tool for locating executables and running them. You can verify by manually running the script instead w/o rosrun.

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Asked: 2011-04-22 09:10:18 -0500

Seen: 695 times

Last updated: Apr 25 '11