下载OpnenCV For Android
OpenCV官网--Release--Android，即可下载到最新的OpenCV的Android版本
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认识一下OpenCV For Android的目录结构
.
├── LICENSE
├── README.android
├── samples
│ ├── 15-puzzle
│ │ ├── AndroidManifest.xml
│ │ ├── build.gradle
│ │ ├── res
│ │ └── src
│ ├── build.gradle
│ ├── camera-calibration
│ │ ├── AndroidManifest.xml
│ │ ├── build.gradle
│ │ ├── res
│ │ └── src
│ ├── color-blob-detection
│ │ ├── AndroidManifest.xml
│ │ ├── build.gradle
│ │ ├── res
│ │ └── src
│ ├── face-detection
│ │ ├── AndroidManifest.xml
│ │ ├── build.gradle
│ │ ├── jni
│ │ ├── res
│ │ └── src
│ ├── gradle
│ │ └── wrapper
│ ├── gradle.properties
│ ├── gradlew
│ ├── gradlew.bat
│ ├── image-manipulations
│ │ ├── AndroidManifest.xml
│ │ ├── build.gradle
│ │ ├── res
│ │ └── src
│ ├── settings.gradle
│ ├── tutorial-1-camerapreview
│ │ ├── AndroidManifest.xml
│ │ ├── build.gradle
│ │ ├── res
│ │ └── src
│ ├── tutorial-2-mixedprocessing
│ │ ├── AndroidManifest.xml
│ │ ├── build.gradle
│ │ ├── jni
│ │ ├── res
│ │ └── src
│ └── tutorial-3-cameracontrol
│ ├── AndroidManifest.xml
│ ├── build.gradle
│ ├── res
│ └── src
└── sdk
├── build.gradle
├── etc
│ ├── haarcascades
│ ├── lbpcascades
│ ├── licenses
│ ├── valgrind_3rdparty.supp
│ └── valgrind.supp
├── java
│ ├── AndroidManifest.xml
│ ├── javadoc
│ ├── res
│ └── src
└── native
├── 3rdparty
├── jni
├── libs
└── staticlibs
下载并配置好NDK
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在SDKTools中，要下载好LLDB，CMake，NDK
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用Studio创建 Native C++工程
Toolchain选C++11
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拷贝OpenCV中的so库到工程中
sdk/
├── build.gradle
├── etc
│ ├── haarcascades
│ ├── lbpcascades
│ ├── licenses
│ ├── valgrind_3rdparty.supp
│ └── valgrind.supp
├── java
│ ├── AndroidManifest.xml
│ ├── javadoc
│ ├── res
│ └── src
└── native
├── 3rdparty
├── jni
├── libs
└── staticlibs
把sdk/native/libs下的so拷贝到工程的app/src/main/jniLibs中
sdk/native/libs/
├── arm64-v8a
│ └── libopencv_java4.so
├── armeabi-v7a
│ └── libopencv_java4.so
├── x86
│ └── libopencv_java4.so
└── x86_64
└── libopencv_java4.so
如下图位置：
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ps:如果不打算支持x86架构，可以不需要拷贝x86开头的那几个
修改CMakeLists.txt
1.添加头文件
# OpenCV 头文件路径
include_directories(/home/andforce/Desktop/opencv-4.1.0-android-sdk/OpenCV-android-sdk/sdk/native/jni/include)
2.引入so
#引入libopencv_java4.so文件
add_library(opencv_java4 SHARED IMPORTED)
set_target_properties(opencv_java4
PROPERTIES
# ${PROJECT_SOURCE_DIR}
# ${CMAKE_CURRENT_SOURCE_DIR}
# ${CMAKE_SOURCE_DIR}
IMPORTED_LOCATION ${CMAKE_SOURCE_DIR}/../jniLibs/${ANDROID_ABI}/libopencv_java4.so
)
3.添加自己的so
# Creates and names a library, sets it as either STATIC
# or SHARED, and provides the relative paths to its source code.
# You can define multiple libraries, and CMake builds them for you.
# Gradle automatically packages shared libraries with your APK.
add_library( # Sets the name of the library.
flood-fill
# Sets the library as a shared library.
SHARED
# Provides a relative path to your source file(s).
cpp_java_utils.cpp
find_objects.cpp
mat_map_cvt.cpp
flood_fill.cpp)
4.添加bitmap支持，一般OpenCV都需要跟Bitmap交互，如果不处理Bitmap，可以不添加
# 支持操作Bitmap的库
find_library( # Sets the name of the path variable.
jnigraphics-lib
# Specifies the name of the NDK library that
# you want CMake to locate.
jnigraphics )
5.最后把自己的库和opencv库添加上
# Specifies libraries CMake should link to your target library. You
# can link multiple libraries, such as libraries you define in this
# build script, prebuilt third-party libraries, or system libraries.
target_link_libraries( # Specifies the target library.
flood-fill
opencv_java4
# Links the target library to the log library
# included in the NDK.
${jnigraphics-lib}
${log-lib})
完整的CMakeLists.txt
# For more information about using CMake with Android Studio, read the
# documentation: https://d.android.com/studio/projects/add-native-code.html
# Sets the minimum version of CMake required to build the native library.
cmake_minimum_required(VERSION 3.4.1)
# OpenCV 头文件路径
include_directories(/home/andforce/Desktop/opencv-4.1.0-android-sdk/OpenCV-android-sdk/sdk/native/jni/include)
#引入libopencv_java4.so文件
add_library(opencv_java4 SHARED IMPORTED)
set_target_properties(opencv_java4
PROPERTIES
# ${PROJECT_SOURCE_DIR}
# ${CMAKE_CURRENT_SOURCE_DIR}
# ${CMAKE_SOURCE_DIR}
IMPORTED_LOCATION ${CMAKE_SOURCE_DIR}/../jniLibs/${ANDROID_ABI}/libopencv_java4.so
)
# Creates and names a library, sets it as either STATIC
# or SHARED, and provides the relative paths to its source code.
# You can define multiple libraries, and CMake builds them for you.
# Gradle automatically packages shared libraries with your APK.
add_library( # Sets the name of the library.
flood-fill
# Sets the library as a shared library.
SHARED
# Provides a relative path to your source file(s).
cpp_java_utils.cpp
find_objects.cpp
mat_map_cvt.cpp
flood_fill.cpp)
# Searches for a specified prebuilt library and stores the path as a
# variable. Because CMake includes system libraries in the search path by
# default, you only need to specify the name of the public NDK library
# you want to add. CMake verifies that the library exists before
# completing its build.
find_library( # Sets the name of the path variable.
log-lib
# Specifies the name of the NDK library that
# you want CMake to locate.
log)
# 支持操作Bitmap的库
find_library( # Sets the name of the path variable.
jnigraphics-lib
# Specifies the name of the NDK library that
# you want CMake to locate.
jnigraphics )
# Specifies libraries CMake should link to your target library. You
# can link multiple libraries, such as libraries you define in this
# build script, prebuilt third-party libraries, or system libraries.
target_link_libraries( # Specifies the target library.
flood-fill
opencv_java4
# Links the target library to the log library
# included in the NDK.
${jnigraphics-lib}
${log-lib})
github demo: https://github.com/andforce/OpenCV4ImportDemo
