ERROR:dn_object_detect/lib/libyololib.so: undefined reference to `cvRound'

[shijiwensjw]

I uesd Ubuntu 16.04 and ros kinectic. When I complied this project, the error is like this:
..._ws/src/dn_object_detect/lib/libyololib.so: undefined reference to `cvRound'
collect2: error: ld returned 1 exit status
dn_object_detect/CMakeFiles/dn_object_detect.dir/build.make:249: recipe for target '..._ws/devel/lib/dn_object_detect/dn_object_detect' failed
make[2]: *** [..._ws/devel/lib/dn_object_detect/dn_object_detect] Error 1
CMakeFiles/Makefile2:1092: recipe for target 'dn_object_detect/CMakeFiles/dn_object_detect.dir/all' failed
make[1]: *** [dn_object_detect/CMakeFiles/dn_object_detect.dir/all] Error 2
Makefile:138: recipe for target 'all' failed
make: *** [all] Error 2
Invoking "make -j8 -l8" failed

Can you tell me what is the reason? How can I solve this?
Thanks!

[kunle12]

#7 might help. make sure your code is compiled to the same version of OpenCV.

[shijiwensjw]

Thank you, but i don't kown how to point the make file to OpenCV2 as he said.
How to do with that?
Thanks