see https://lcas.lincoln.ac.uk/buildfarm/job/Kdev__strands_social__ubuntu_xenial_amd64/3/console: ``` /tmp/catkin_workspace/src/strands_social/datamatrix_read/src/data_matrix.cpp:49:5: error: ‘imwrite’ is not a member of ‘cv’ ``` @Jailander can you quickly check what is wrong with this. Probably some simple opencv header issue.