1.

./mx_csmp: error while loading shared libraries: libopencv_flann.so.3.4: cannot open shared object file: No such file or directory

这个错误表明你的系统找不到 libopencv_flann.so.3.4 共享库

查看一下我的系统上安装的是 OpenCV 4.2.0，而问题是缺少 libopencv_flann.so.3.4，这是我的程序为 OpenCV 3.4 构建的

linux@ubuntu:/media/linux/Projects_tool/csmp_onboard/output/csmp/pc/Linux/x86_64/Release$ dpkg -l | grep libopencv-dev
ii  libopencv-dev                              4.2.0+dfsg-5                               amd64        development files for opencv
linux@ubuntu:/media/linux/Projects_tool/csmp_onboard/output/csmp/pc/Linux/x86_64/Release$ 

解决办法

① 临时解决  创建符号链接（但这不是推荐的做法，可能导致兼容性问题）

sudo ln -s /usr/lib/x86_64-linux-gnu/libopencv_flann.so.4.2 /usr/lib/x86_64-linux-gnu/libopencv_flann.so.3.4

②安装 OpenCV 3.4