Opencv4, now working

[kunaltyagi]

This is a followup to the previous PR and sports a working compilation with OpenCV4. Please note that the submodule has been changed to point to my own fork of darknet.

I've created a PR on the original one but repointed the submodule to still keep everything working.

[mbjelonic]

Thanks for the commit. Just for clarification: The changes that you created enables us to use the latest darknet version?
I would like to have this pull request merged as soon as your PR to the original darknet is done. Then we can update the submodule to latest commit of the original darknet.
Marko

[kunaltyagi]

I started the PR so others could start using/modifying it. Still a WIP at my place. We'll be upstreaming the bug-fixes as fast as possible.

It doesn't yet use the upstream darknet, so don't merge it, at least not yet.

[kunaltyagi]

Here I was recommended to use AlexeyAB/darknet instead which also comes with a CMake and seems to be more active. Maybe a switch to the other fork is a better idea.

[pat-langevin]

I tried your commit for my project and it worked! But sometimes my laptop crashes for whatever reasons, I checked the ram, the gpu, heat and everything seems fine so it may not be related to this project. One thing tho is the camera output of this version, mine looks blueish, Is it also your case? Otherwise great job! I was looking for a version that uses opencv 4 and you saved me a lot of trouble. Thanks

[kunaltyagi]

mine looks blueish

Yeah, darknet needs BGR but the actual image is RGB (or some issue like that)

[klintan]

Any news on this PR ? As suggested: Maybe switch to the more active darknet fork instead of the original.

[cxhmikegithub]

@kunaltyagi I use AlexeyAB/darknet instead pjreddie/darknet in darknet_ros, but numbers of errors occur:
CMake Error at /usr/local/share/cmake-3.13/Modules/FindCUDA.cmake:1820 (add_library):
Cannot find source file:
/home/nvidia/cola/catkin_test/src/darknet_ros/darknet/src/cuda.c
Tried extensions .c .C .c++ .cc .cpp .cxx .cu .m .M .mm .h .hh .h++ .hm
.hpp .hxx .in .txx

CMake Error at /usr/local/share/cmake-3.13/Modules/FindCUDA.cmake:1820 (add_library):
No SOURCES given to target: darknet_ros_lib

can you help me ? Thank you

[kunaltyagi]

I actually stopped mid-way in porting to AlexyAB due to some linker issues. My (partial) work is available at https://github.com/kunaltyagi/darknet_ros/tree/alexeyab and I welcome contributions to help improve it.

[cxhmikegithub]

@kunaltyagi thank you , I tried your work , and receive errors:
/home/nvidia/cola/catkin_ws/src/darknet_ros-alexeyab/darknet_ros/src/YoloObjectDetector.cpp:373:25: error: ‘mat_to_image’ was not declared in this scope
buff_[buffIndex_] = mat_to_image(ROS_img);
^~~~~~~~~~~~
/home/nvidia/cola/catkin_ws/src/darknet_ros-alexeyab/darknet_ros/src/YoloObjectDetector.cpp:373:25: note: suggested alternative: ‘float_to_image’
buff_[buffIndex_] = mat_to_image(ROS_img);
^~~~~~~~~~~~
float_to_image

I find mat_to_image in YoloObjectDetector.cpp, it was not declared indeed

[kunaltyagi]

I'm aware of the error. Can't proceed beyond either a compile or linker error for these 2 functions. Please discuss this on my fork, and let's not pollute here with unrelated issues 😄