Open CV and CV Bridge

[alfa budiman]

I'd like to share my experience installing these packages on the RB5 drone. It was not pleasant but it got done.

I tried several variations of pip install opencv-python, with different versions of opencv and pip / pip2 / pip3, none of those worked. I tried sudo apt install and that didn't work. Similar issues popped up trying CV Bridge.

Ultimately, I ended up having to build these packages from source (I think that's the right term). I followed the steps here: https://pyimagesearch.com/2015/06/22/install-opencv-3-0-and-python-2-7-on-ubuntu/
to install opencv. I ignored steps 8 and 9.

To install CV Bridge, first I installed opencv as per the linked instructions. Then, I repeated the linked instructions step 10 but with the github repo for CV Bridge (https://github.com/ros-perception/vision_opencv). After this, you must edit the ~/.bashrc on the drone and enter the following:

export LD_LIBRARY_PATH=/usr/local/lib

These packages can then be used for computer vision work with camera imagery from voxl_mpa_to_ros_node. If anyone was able to install these packages using just pip install, I'd like to know how, as I believe this issue, of having to install from source may pop up in other packages I try to install on the drone.