[Report] `OpenCV` path problem in building `realsense-ros`

[bigbellmercy]

In catkin_make clean and catkin_make commands for building realsense-ros for the first time in the system (Jetson Nano), the errors such as the following happen much recently. But, it succeeded ago in the same environment.

Error

/opt/ros/melodic/include/cv_bridge/cv_bridge.h:43:10: fatal error: opencv2/core/core.hpp: No such file or directory
 #include <opencv2/core/core.hpp>
          ^~~~~~~~~~~~~~~~~~~~~~~

Solution

There is no /usr/include/opencv but there is /usr/include/opencv4. So, after making a link file as following command, the problem disappeared: In /usr/include folder, sudo ln -s opencv4 opencv

Environment

realsense-ros v2.2.22 ROS melodic Ubuntu 18.04 Jetson Nano (Arm86)

Build

I was trying the 'Step 2: Install Intel® RealSense™ ROS from Sources' in the site for build.

[MartyG-RealSense]

Thanks very much @bigbellmercy for sharing your solution with the RealSense ROS community!

@doronhi Do you have any thoughts about why the above problem with /usr/include/opencv may have occurred on Nano for @bigbellmercy please?

[MartyG-RealSense]

@doronhi Do you have any thoughts about why the above problem with /usr/include/opencv may have occurred on Nano for @bigbellmercy please? Thanks!

[MartyG-RealSense]

Hi @bigbellmercy Are you still having the problem described in this case, please?

[bigbellmercy]

Hi~ @MartyG-RealSense, this problem must happens all the recent users of Jetson Nano because it happens when using the Jetson Nano SD card latest image file jetson-nano-jp451-sd-card-image.zip. In this jp451 version, opencv is not installed /usr/include/opencv but /usr/include/opencv4 because the recent version of opencv use the folder opencv4 as I heard, but realsense-ros uses the old path opencv. So, it seems better that realsense-ros coup with this new opencv path problem.

[MartyG-RealSense]

Thanks very much @bigbellmercy - I think it will be useful to keep this case open for a couple of weeks to wait and see if any other Nano users report a similar experience to yours. Thanks again!

[doronhi]

Hi, sorry for failing to notice this issue. opencv is not a direct requirement of realsense2_camera. cv_bridge is. It seems that the issue is with the cv_bridge package, rather than the realsense2_camera package. Looking at the source code of cv_bridge they seem to address the issue. Until further investigation on my part, I cannot say how best realsense2_camera can deal with this situation. I opened an inner ticket: DSO-16886 but I expect it will take a while.

[huangwen0907]

I have the similar problem and modified the file cv_bridgeConfig.cmake. change the old path from: set(_include_dirs "include;/usr/include;/usr/include/opencv") to: set(_include_dirs "include;/usr/include;/usr/include/opencv4;/usr/include/opencv4/opencv2") and can fix the problem.
I know this is not good for the system, but I do not know the other ways

[MartyG-RealSense]

Thanks very much @huangwen0907 for sharing your method!

[JoKoll]

Has there been an update to this problem? I'm currently encountering the same issue and haven't been able to build the realsense-ros package.

Environment realsense-ros branch 3e569d8 Intel Realsense SDK (v2.49.0) ROS melodic Ubuntu 18.04 Jetson TX2

Error `In file included from /home/jackaltx2/catkin_ws/src/realsense-ros/realsense2_camera/src/../include/realsense_node_factory.h:16:0, from /home/jackaltx2/catkin_ws/src/realsense-ros/realsense2_camera/src/realsense_node_factory.cpp:4: /opt/ros/melodic/include/cv_bridge/cv_bridge.h:43:10: fatal error: opencv2/core/core.hpp: No such file or directory

include <opencv2/core/core.hpp>

      ^~~~~~~~~~~~~~~~~~~~~~~

compilation terminated. realsense-ros/realsense2_camera/CMakeFiles/realsense2_camera.dir/build.make:62: recipe for target 'realsense-ros/realsense2_camera/CMakeFiles/realsense2_camera.dir/src/realsense_node_factory.cpp.o' failed make[2]: [realsense-ros/realsense2_camera/CMakeFiles/realsense2_camera.dir/src/realsense_node_factory.cpp.o] Error 1 make[2]: Waiting for unfinished jobs.... In file included from /home/jackaltx2/catkin_ws/src/realsense-ros/realsense2_camera/src/../include/../include/realsense_node_factory.h:16:0, from /home/jackaltx2/catkin_ws/src/realsense-ros/realsense2_camera/src/../include/base_realsense_node.h:6, from /home/jackaltx2/catkin_ws/src/realsense-ros/realsense2_camera/src/base_realsense_node.cpp:1: /opt/ros/melodic/include/cv_bridge/cv_bridge.h:43:10: fatal error: opencv2/core/core.hpp: No such file or directory

include <opencv2/core/core.hpp>

      ^~~~~~~~~~~~~~~~~~~~~~~

compilation terminated. `

I first encountered the "opencv_bridge" error when attempting to use "catkin_make clean" in Step 2 of Method 2 in the realsense-ros github page. Creating the symbolic link similar to the OP of this thread solved the issue. However when compiling the catkin_ws I got the same error. I performed the symbolic linking as instructed above, but it did not solve the problem for me. I'm hesistant to change the cv_bridgeConfig.cmake file as huangwen0907 suggested since I am running other programs with ROS.

Have other solutions been found?

[MartyG-RealSense]

Hi @JoKoll A RealSense ROS user who also recently had problems with cv_bridge during installation achieved a successful build by using sudo apt-get install ros-melodic-realsense2-camera and also performing "a clean catkin_make of all the workspace". https://github.com/IntelRealSense/realsense-ros/issues/2078#issuecomment-926456214

[dnovischi]

Hi @JoKoll,

You can try to follow the tutorials I just put up right now here. Most likely it will solve many of the problems you encounter.

Cheers.

[MartyG-RealSense]

Case closed due to RealSense ROS1 wrapper no longer being updated.