Mac M1编译OpenCV获取libopencv_java490.dylib文件

Window OpenCV下载地址

https://opencv.org/releases/

OpenCV源码下载

https://github.com/opencv/opencv/tree/4.9.0
https://github.com/opencv/opencv_contrib/tree/4.9.0

OpenCV依赖

brew install libjpeg libpng libtiff cmake3 ant freetype

构建open CV

cmake -G Ninja \
  -DCMAKE_BUILD_TYPE=Release \
  -DCMAKE_OSX_ARCHITECTURES="arm64;x86_64" \
  -DWITH_IPP=OFF \
  -DWITH_TBB=OFF \
  -DWITH_OPENCL=OFF \
  -DENABLE_NEON=OFF \
  -DCPU_BASELINE="" \
  -DCPU_DISPATCH="" \
  -DBUILD_opencv_dnn=OFF \
  -DBUILD_JAVA=ON \
  -DPNG_ARM_NEON_OPT=0 \
  -DBUILD_opencv_imgcodecs=ON \
  -DBUILD_opencv_ml=OFF \
  -DBUILD_LIST="core;java" \
  -DCV_DISABLE_OPTIMIZATION=ON \
  -DBUILD_opencv_python=OFF \
  -DOPENCV_EXTRA_MODULES_PATH=/Users/youshang/Downloads/opencv_contrib-4.9.0/modules \
  -DJAVA_AWT_INCLUDE_PATH=$JAVA_HOME/include \
  -DJAVA_AWT_LIB=$JAVA_HOME/lib/libjawt.dylib \
  -DJAVA_INCLUDE_PATH=$JAVA_HOME/include \
  -DJAVA_INCLUDE_PATH2=$JAVA_HOME/include/darwin \
  -DJAVA_JVM_LIBRARY=$JAVA_HOME/lib/server/libjvm.dylib \
  ..

• 注意-DCMAKE_OSX_ARCHITECTURES、-DBUILD_LIST参数,仅仅是为了编译成功，里面缺了很多模块
• 编译出来只能使用本地库，jar功能不全选择maven仓库下载替换

构建完成标志：

编译opencv

ninja

编译完成标志：

• 编译opencv为了获取 libopencv_java490文件
• 文件存放路径为：opencv-4.9.0/build/lib (不要使用构建成功的jar包，jar包单独下载)
• libopencv_java490.dylib Mac依赖的 OpenCV本地库
• opencv_java490.dll window依赖的OpenCV本地库

项目中集成OpenCV

配置libopencv_java490文件

• 将libopencv_java490文件丢到 /usr/local/lib 目录下，在项目中加载OpenCV本地库

    static {
				// 加载 OpenCV 本地库
        System.loadLibrary(Core.NATIVE_LIBRARY_NAME);
    }

• idea添加VM options引用

  -Djava.library.path=/usr/local/lib
  

  

配置openCV jar包

        <dependency>
            <groupId>com</groupId>
            <artifactId>opencv</artifactId>
            <version>4.9.0</version>
            <scope>system</scope>
            <systemPath>${project.basedir}/libs/opencv-4.9.0-0.jar</systemPath>
        </dependency>

异常信息：

no opencv_java490

Exception in thread "main" java.lang.UnsatisfiedLinkError: no opencv_java490 in java.library.path: [/Users/youshang/Library/Java/Extensions, /Library/Java/Extensions, /Network/Library/Java/Extensions, /System/Library/Java/Extensions, /usr/lib/java, .]
	at java.base/java.lang.ClassLoader.loadLibrary(ClassLoader.java:2678)
	at java.base/java.lang.Runtime.loadLibrary0(Runtime.java:830)
	at java.base/java.lang.System.loadLibrary(System.java:1890)
	at com.rangertech.osc.video.utils.CameraCalibrationJava.<clinit>(CameraCalibrationJava.java:26)

• 原因：未配置libopencv_java490所导致的
• 解决方法：将libopencv_java490配置到-Djava.library.path= 读取的位置即可

long org.opencv.imgcodecs.Imgcodecs.imread_1(java.lang.String)

Exception in thread "main" java.lang.UnsatisfiedLinkError: 'long org.opencv.imgcodecs.Imgcodecs.imread_1(java.lang.String)'
	at org.opencv.imgcodecs.Imgcodecs.imread_1(Native Method)
	at org.opencv.imgcodecs.Imgcodecs.imread(Imgcodecs.java:330)
	at com.rangertech.osc.video.utils.CameraCalibrationJava.calibration(CameraCalibrationJava.java:83)
	at com.rangertech.osc.video.utils.CameraCalibrationJava.main(CameraCalibrationJava.java:192)

• 原因：有可能是jdk架构、libopencv_java490版本、libopencv_java490编译架构，不一致导致的

• 解决方法：单独下载opencv jar包

  • 下载地址：https://repo1.maven.org/maven2/org/openpnp/opencv/4.9.0-0/

  • 在调用时主动加载OpenCV：

        public static void main(String[] args) {
    
            //加载openCV
            PrintVersion.main(args);
    
            CameraCalibrationDTO dto = new CameraCalibrationDTO();
            dto.setChessboardHeight(6);
            dto.setChessboardWidth(9);
            dto.setSquareSize(24.0);
            dto.setImagePaths(Lists.newArrayList("/Users/youshang/Downloads
                                                 /Checkerboard.png"));
            CameraCalibrationJava.calibration(dto);
        }
    

zsh: command not found:

CMake Error: The source directory "/Users/youshang/Downloads/opencv-4.9.0/build/ " does not exist.
Specify --help for usage, or press the help button on the CMake GUI.
zsh: command not found: -DBUILD_JAVA=ON

• 原因：
  • CMake 提示找不到 …/opencv-4.9.0/build/ 目录，原因是路径末尾多了一个空格；
  • 终端报 “zsh: command not found: -DBUILD_JAVA=ON” 往往是因为换行符 \ 后面不小心留了空格，导致 shell 没把它当作续行符处理，接下来的参数被当成了新的命令。