官网：https://opencv.org/releases/ 下载Sources包，我测试下载的是3.4.16
安卓opencv依赖库：百度一下”linux编译opencv”

Linux编译：

mkdir build
cd build
cmake -D WITH_TBB=ON -D WITH_EIGEN=OFF -D OPENCV_GENERATE_PKGCONFIG=ON  -D BUILD_DOCS=ON -D BUILD_TESTS=OFF -D BUILD_PERF_TESTS=OFF -D BUILD_EXAMPLES=OFF  -D WITH_OPENCL=OFF -D WITH_CUDA=OFF -D BUILD_opencv_gpu=OFF -D BUILD_opencv_gpuarithm=OFF -D BUILD_opencv_gpubgsegm=O -D CMAKE_BUILD_TYPE=RELEASE -D CMAKE_INSTALL_PREFIX=/usr/local/opencv3.4.16 ..
make -j8
make install

静态编译加上： -DBUILD_SHARED_LIBS=OFF
cmake find_library路径为：opencv安装路径/share/OpenCV

安卓交叉编译：

mkdir build
cd build
cmake -DCMAKE_TOOLCHAIN_FILE=$ANDROID_NDK/build/cmake/android.toolchain.cmake \
-DCMAKE_ANDROID_NDK=$ANDROID_NDK \
-DANDROID_NATIVE_API_LEVEL=29 \
-DANDROID_ABI="arm64-v8a" \
-DBUILD_ANDROID_PROJECTS=OFF \
-DBUILD_ANDROID_EXAMPLES=OFF \
-DCMAKE_BUILD_TYPE=Release  \
-DBUILD_JAVA=OFF  \
-DBUILD_SHARED_LIBS=OFF \
-DBUILD_opencv_world=OFF \   
-DCMAKE_INSTALL_PREFIX=/root/cross-compile-test/3rdparty/opencv-Android-static ..
make -j8
make install

cmake find_library路径为：opencv安装路径/sdk/native/jni

cmake使用opencv：

Linux：
set(OpenCV_DIR opencv-Linux-static/share/OpenCV) 
find_package(OpenCV REQUIRED)
include_directories(${OpenCV_INCLUDE_DIRS})
target_link_libraries(main ${OpenCV_LIBS})

安卓：
set(OpenCV_DIR opencv-Android-shared/sdk/native/jni)
find_package(OpenCV REQUIRED)
include_directories(${OpenCV_INCLUDE_DIRS})
target_link_libraries(main ${OpenCV_LIBS})