Hi

if I want to start rqt_image_view via rosrun rqt_image_view rqt_image_view or just rqt_image_view then I get the following error:

[ERROR] [1592863606.174353422]: Failed to load nodelet [rqt_image_view/ImageView_0] of type [rqt_image_view/ImageView]: Failed to load library /opt/ros/melodic/lib//librqt_image_view.so. Make sure that you are calling the PLUGINLIB_EXPORT_CLASS macro in the library code, and that names are consistent between this macro and your XML. Error string: Could not load library (Poco exception = libopencv_core.so.3.2: cannot open shared object file: No such file or directory)
RosPluginlibPluginProvider::load_explicit_type(rqt_image_view/ImageView) failed creating instance
PluginManager._load_plugin() could not load plugin "rqt_image_view/ImageView": RosPluginlibPluginProvider.load() could not load plugin "rqt_image_view/ImageView"
terminate called after throwing an instance of 'boost::exception_detail::clone_impl<boost::exception_detail::error_info_injector<boost::lock_error> >'
pure virtual method called
terminate called recursively
Aborted (core dumped)

the same happens for rosrun image_view image_view

[ INFO] [1592863868.679032143]: Initializing nodelet with 12 worker threads.
[ERROR] [1592863868.692291840]: Failed to load nodelet [/image_view] of type [image_view/image] even after refreshing the cache: Failed to load library /opt/ros/melodic/lib//libimage_view.so. Make sure that you are calling the PLUGINLIB_EXPORT_CLASS macro in the library code, and that names are consistent between this macro and your XML. Error string: Could not load library (Poco exception = libopencv_core.so.3.2: cannot open shared object file: No such file or directory)
[ERROR] [1592863868.692331964]: The error before refreshing the cache was: Failed to load library /opt/ros/melodic/lib//libimage_view.so. Make sure that you are calling the PLUGINLIB_EXPORT_CLASS macro in the library code, and that names are consistent between this macro and your XML. Error string: Could not load library (Poco exception = libopencv_core.so.3.2: cannot open shared object file: No such file or directory)

The problem is that this file /libimage_view.so does not exist. The ros installation works fine for all other things (rviz, rqt_plot, ...). The only problem is the image data.

I also tried to this:

sudo apt-get install ros-melodic-rqt-image-view
Reading package lists... Done
Building dependency tree       
Reading state information... Done
ros-melodic-rqt-image-view is already the newest version (0.4.14-1bionic.20200530.125139).
ros-melodic-rqt-image-view set to manually installed.
0 to upgrade, 0 to newly install, 0 to remove and 0 not to upgrade.

sudo apt-get install ros-melodic-image-view
Reading package lists... Done
Building dependency tree       
Reading state information... Done
ros-melodic-image-view is already the newest version (1.15.0-1bionic.20200530.133102).
ros-melodic-image-view set to manually installed.
0 to upgrade, 0 to newly install, 0 to remove and 0 not to upgrade.

Edit: locate lilibopencv_core.so:

user@neworder-ph:~$ locate libopencv_core.so
/home/user/opencv_build/opencv/build/lib/libopencv_core.so
/home/user/opencv_build/opencv/build/lib/libopencv_core.so.4.3
/home/user/opencv_build/opencv/build/lib/libopencv_core.so.4.3.0
/usr/local/lib/libopencv_core.so
/usr/local/lib/libopencv_core.so.4.3
/usr/local/lib/libopencv_core.so.4.3.0

Does someone have a solution to this problem?

Thanks

sudo apt install ros-melodic-rqt-image-view

Could not load library (Poco exception = libopencv_core.so.3.2: cannot open shared object file: No such file or directory)