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'''Diamondback Users Please Note'''

With the release of Diamondback, the Python Camshift function in OpenCV somehow got broken and will crash with the following error:

{{{
TypeError: <unknown> is not a numpy array
}}}

right after selecting a region with the mouse to track.  The only fix at the moment seems to be to overlay the C-Turtle version of the vision_opencv stack and then set your ROS_PACKAGE_PATH and PYTHONPATH environment variables to pick up this version before Diamondback's version.  To do this on your machine, follow these steps:

{{{
$ sudo apt-get install ros-cturtle-vision-opencv
$ cd
$ echo -e "\nexport ROS_PACKAGE_PATH=/opt/ros/cturtle/stacks/vision_opencv:$ROS_PACKAGE_PATH" >> .bashrc
$ echo -e "\nexport PYTHONPATH=/opt/ros/cturtle/stacks/vision_opencv/opencv2/lib:$PYTHONPATH" >> .bashrc
$ source .bashrc
}}}

(The last command is only necessary in any currently open terminal windows. The path changes will be automatically picked up in any new terminal windows you launch in the future.)

== Documentation ==
Please see external documentation at [[http://www.pirobot.org/blog/0016|http://www.pirobot.org/blog/0016/]].

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