在 ROS 中使用 cv::FileStorage 加载 YML 文件时出现分段错误

Question

I have a problem with cv::FileStorage when I tried to read a YML file in a ROS node. I got Segmentation fault (core dumped) error when running the node and I was able to identified the problem which comes from the calling of cv::FileStorage constructor. Then, according to this similar question, I put the following code in main function (separately in a node), but the error still occurs, due to the fs.open(...) function.

Remark that I linked the necessary packages with my ros package, and I provided the absolute path to the file as well.

std::string filePath = "/home/user/catkin_ws/src/arucov3_node/param/raspicam_v2_400x300.yml";
cv::FileStorage fs;
try{
    fs.open(filePath, cv::FileStorage::READ);
}
catch(cv::Exception ex){
    ROS_ERROR("%s", ex.what());
    return 0;
}

For providing more information about this issue, I tried to debug with gdb and got the detailed error message:

Thread 1 "detect_node" received signal SIGSEGV, Segmentation fault. 0x00007ffff51e4a18 in cv::FileStorage::Impl::release(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >*) [clone.constprop.330] ()

Hope someone could help me for this problem.

Answer 1

I figured out this issue based on PaulMcKenzie's comments. It was a version problem of OpenCV. Actually, aside from binary installed OpenCV 3.2.0 in Ubuntu, I have built OpenCV 4.5.2 from source, with which my program is linked and didn't work.

So I specify in CMakeLists.txt : find_package(OpenCV 3.2.0 REQUIRED) Then it is working.

I felt so strange about that a newer version of OpenCV doesn't work with such a basic function. Not sure if it was me who have missed anything.

I update my response by giving more details:

The 4.5.2 version of OpenCV didn't work for some reasons, so I rebuilt it by cloning the 3.4 branch of OpenCV . (The default 3.2.0 version in Ubuntu lacks some of the latest functionalities)

Since I have built my package (and also another library from source) based on OpenCV 4.5.2, I need to rebuild everything giving the path to the same version of OpenCV.Basically it was simply adding an argument while compiling by cmake or catkin, like cmake -DOpenCV_DIR=<pathTo-OpenCVConfig.cmake>..

Answer 2

Not sure if it's related to your issue without seeing the rest of your code, but OpenCV exceptions are not copyable, so your catch won't work. Try this, you might have an actual error message instead:

catch(const cv::Exception& e){
    ROS_ERROR("%s", e.what());
    //... abort or continue
}