Ubuntu22.04下如何通过CMake install打包项目所需OpenCV依赖

问题背景 #

在Ubuntu22.04环境下通过sudo apt-get安装了OpenCV作为项目依赖，目标部署机器未安装OpenCV且无sudo权限，需要通过CMake的install命令将用到的OpenCV库打包为可移植版本，执行make install时自动复制所需库文件。

尝试过程与错误 #

使用的CMakeLists.txt片段：

find_package( OpenCV REQUIRED )

message("OpenCV_LIBS:")
foreach(lib  ${OpenCV_LIBS})
message("${lib}")
endforeach()

install(FILES ${OpenCV_LIBS} TYPE LIB)

执行cmake ..输出：

OpenCV_LIBS:
opencv_calib3d
opencv_core
opencv_dnn
opencv_features2d
opencv_flann
opencv_highgui
//省略部分同类输出

执行make install时触发错误：

CMake Error at cmake_install.cmake:130 (file):
  file INSTALL cannot find "/home/john/myproject/opencv_calib3d":
  No such file or directory.

额外需求：如何只提供二进制程序实际依赖的OpenCV库，而非全部OpenCV组件？（目标机器为同版本Ubuntu）

问题分析 #

${OpenCV_LIBS}变量存储的是OpenCV库的逻辑名称（如opencv_core），而非库文件的绝对路径，因此CMake无法在当前项目目录下找到对应文件，导致安装失败。

解决方案 #

1. 正确获取OpenCV库路径并安装 #

修改CMake代码，通过get_target_property获取每个OpenCV库的实际文件路径，再执行安装：

find_package(OpenCV REQUIRED)

# 收集所有OpenCV库的绝对路径
set(OPENCV_LIB_FILES "")
foreach(lib ${OpenCV_LIBS})
    get_target_property(lib_path ${lib} LOCATION)
    if(lib_path)
        list(APPEND OPENCV_LIB_FILES ${lib_path})
        message("Found OpenCV library: ${lib_path}")
    endif()
endforeach()

# 安装OpenCV库到指定目录（默认CMAKE_INSTALL_PREFIX为/usr/local，可自定义）
install(FILES ${OPENCV_LIB_FILES} DESTINATION ${CMAKE_INSTALL_PREFIX}/lib)

# 可选：安装OpenCV头文件（若需在目标机器编译依赖代码则添加）
install(DIRECTORY ${OpenCV_INCLUDE_DIRS}/ DESTINATION ${CMAKE_INSTALL_PREFIX}/include/opencv)

执行cmake ..时会输出每个库的绝对路径，确认路径无误后执行make install即可完成库文件复制。

2. 仅打包实际依赖的OpenCV库 #

针对同系统部署场景，有两种高效方法：

方法一：用ldd手动分析依赖

编译完成项目二进制后，执行以下命令列出实际依赖的OpenCV库：

ldd ./your_project_binary | grep opencv

提取输出中的库文件绝对路径，替换CMake中OPENCV_LIB_FILES的内容，即可只安装这些必要库。

方法二：CMake自动收集运行时依赖

通过CMake的file(GET_RUNTIME_DEPENDENCIES)命令自动提取二进制的运行时依赖，仅安装涉及OpenCV的部分：

# 先安装项目二进制文件
install(TARGETS your_project_binary DESTINATION bin)

# 自动收集并安装依赖的OpenCV库
install(CODE "
    file(GET_RUNTIME_DEPENDENCIES
        EXECUTABLES \$<TARGET_FILE:your_project_binary>
        RESOLVED_DEPENDENCIES_VAR RESOLVED_DEPS
        UNRESOLVED_DEPENDENCIES_VAR UNRESOLVED_DEPS
    )
    foreach(dep \${RESOLVED_DEPS})
        if(dep MATCHES \"opencv\")
            file(INSTALL
                DESTINATION \${CMAKE_INSTALL_PREFIX}/lib
                TYPE SHARED_LIBRARY
                FILES \"\${dep}\"
            )
        endif()
    endforeach()
")

该方法会自动识别二进制实际需要的OpenCV库，无需手动筛选。

内容的提问来源于stack exchange，提问作者John