Window+NDK+Opencv编译+AS集成

下载opencv

https://github.com/opencv/opencv/releases

编译指令

cmake .. -G "Ninja" \
-DCMAKE_TOOLCHAIN_FILE="G:/SDK/ndk/26.0.10792818/build/cmake/android.toolchain.cmake" \
-DANDROID_NDK="G:/SDK/ndk/26.0.10792818" \
-DANDROID_ABI="arm64-v8a" \
-DANDROID_NATIVE_API_LEVEL=21 \
-DCMAKE_BUILD_TYPE=Release \
-DANDROID_STL=c++_shared \
-DBUILD_SHARED_LIBS=ON \
-DANDROID_TOOLCHAIN=clang \
-DANDROID_PLATFORM=android-21 \
-DCMAKE_VERBOSE_MAKEFILE=ON  \
-DBUILD_ANDROID_PROJECTS=OFF  \
-DBUILD_ANDROID_EXAMPLES=OFF  \
-DBUILD_JAVA=OFF


cmake .. -G "Ninja" -DCMAKE_TOOLCHAIN_FILE="G:/SDK/ndk/26.0.10792818/build/cmake/android.toolchain.cmake" \
-DANDROID_NDK="G:/SDK/ndk/26.0.10792818" \
-DANDROID_ABI="armeabi-v7a" \
-DANDROID_NATIVE_API_LEVEL=21 \
-DCMAKE_BUILD_TYPE=Release \
-DANDROID_STL=c++_shared \
-DBUILD_SHARED_LIBS=ON \
-DANDROID_TOOLCHAIN=clang \
-DANDROID_PLATFORM=android-21 \
-DCMAKE_BUILD_TYPE=Release  \
-DCMAKE_VERBOSE_MAKEFILE=ON \
-DBUILD_ANDROID_PROJECTS=OFF  \
-DBUILD_ANDROID_EXAMPLES=OFF  \
-DBUILD_JAVA=OFF  

ninja

报错 Android SDK Build Tools: directory doesn’t exist:

-- Performing Test HAVE_CXX_WNO_COMMA - Success
-- Update variable ANDROID_HOME from environment: G:/SDK/platform-tools
-- Android SDK: using location: G:/SDK/platform-tools
CMake Error at cmake/android/OpenCVDetectAndroidSDK.cmake:101 (message):
  Android SDK Build Tools: directory doesn't exist:
  G:/SDK/platform-tools/build-tools Use BUILD_ANDROID_PROJECTS=OFF to prepare
  Android project files without building them
Call Stack (most recent call first):
  cmake/android/OpenCVDetectAndroidSDK.cmake:173 (ocv_detect_android_sdk_build_tools)
  CMakeLists.txt:848 (include)

解决：修改ANDROID_HOME路径如下


注意：命令行需要重新打开

生成Makefile成功

--
-- General configuration for OpenCV 4.10.0 =====================================
--   Version control:               unknown
--
--   Platform:
--     Timestamp:                   2025-02-26T09:22:15Z
--     Host:                        Windows 10.0.19045 AMD64
--     Target:                      Android 1 aarch64
--     CMake:                       3.31.2
--     CMake generator:             Ninja
--     CMake build tool:            G:/MSYS2/mingw64/bin/ninja.exe
--     Configuration:               Release
--
--   CPU/HW features:
--     Baseline:                    NEON FP16
--     Dispatched code generation:  NEON_DOTPROD NEON_FP16 NEON_BF16
--       requested:                 NEON_FP16 NEON_BF16 NEON_DOTPROD
--       NEON_DOTPROD (1 files):    + NEON_DOTPROD
--       NEON_FP16 (2 files):       + NEON_FP16
--       NEON_BF16 (0 files):       + NEON_BF16
--
--   C/C++:
--     Built as dynamic libs?:      YES
--     C++ standard:                11
--     C++ Compiler:                G:/SDK/ndk/26.0.10792818/toolchains/llvm/prebuilt/windows-x86_64/bin/clang++.exe  (ver 17.0.2)
--     C++ flags (Release):         -g -DANDROID -fdata-sections -ffunction-sections -funwind-tables -fstack-protector-strong -no-canonical-prefixes -D_FORTIFY_SOURCE=2 -Wformat -Werror=format-security     -fsigned-char -W -Wall -Wreturn-type -Wnon-virtual-dtor -Waddress -Wsequence-point -Wformat -Wformat-security -Wmissing-declarations -Wmissing-prototypes -Wstrict-prototypes -Wundef -Winit-self -Wpointer-arith -Wshadow -Wsign-promo -Wuninitialized -Winconsistent-missing-override -Wno-delete-non-virtual-dtor -Wno-unnamed-type-template-args -Wno-comment -Wno-deprecated-enum-enum-conversion -Wno-deprecated-anon-enum-enum-conversion -fdiagnostics-show-option -Qunused-arguments -ffunction-sections -fdata-sections    -fvisibility=hidden -fvisibility-inlines-hidden -O3 -DNDEBUG   -DNDEBUG
--     C++ flags (Debug):           -g -DANDROID -fdata-sections -ffunction-sections -funwind-tables -fstack-protector-strong -no-canonical-prefixes -D_FORTIFY_SOURCE=2 -Wformat -Werror=format-security     -fsigned-char -W -Wall -Wreturn-type -Wnon-virtual-dtor -Waddress -Wsequence-point -Wformat -Wformat-security -Wmissing-declarations -Wmissing-prototypes -Wstrict-prototypes -Wundef -Winit-self -Wpointer-arith -Wshadow -Wsign-promo -Wuninitialized -Winconsistent-missing-override -Wno-delete-non-virtual-dtor -Wno-unnamed-type-template-args -Wno-comment -Wno-deprecated-enum-enum-conversion -Wno-deprecated-anon-enum-enum-conversion -fdiagnostics-show-option -Qunused-arguments -ffunction-sections -fdata-sections    -fvisibility=hidden -fvisibility-inlines-hidden -fno-limit-debug-info   -O0 -DDEBUG -D_DEBUG
--     C Compiler:                  G:/SDK/ndk/26.0.10792818/toolchains/llvm/prebuilt/windows-x86_64/bin/clang.exe
--     C flags (Release):           -g -DANDROID -fdata-sections -ffunction-sections -funwind-tables -fstack-protector-strong -no-canonical-prefixes -D_FORTIFY_SOURCE=2 -Wformat -Werror=format-security    -fsigned-char -W -Wall -Wreturn-type -Wnon-virtual-dtor -Waddress -Wsequence-point -Wformat -Wformat-security -Wmissing-declarations -Wmissing-prototypes -Wstrict-prototypes -Wundef -Winit-self -Wpointer-arith -Wshadow -Wsign-promo -Wuninitialized -Winconsistent-missing-override -Wno-delete-non-virtual-dtor -Wno-unnamed-type-template-args -Wno-comment -Wno-deprecated-enum-enum-conversion -Wno-deprecated-anon-enum-enum-conversion -fdiagnostics-show-option -Qunused-arguments -ffunction-sections -fdata-sections    -fvisibility=hidden -fvisibility-inlines-hidden -O3 -DNDEBUG   -DNDEBUG
--     C flags (Debug):             -g -DANDROID -fdata-sections -ffunction-sections -funwind-tables -fstack-protector-strong -no-canonical-prefixes -D_FORTIFY_SOURCE=2 -Wformat -Werror=format-security    -fsigned-char -W -Wall -Wreturn-type -Wnon-virtual-dtor -Waddress -Wsequence-point -Wformat -Wformat-security -Wmissing-declarations -Wmissing-prototypes -Wstrict-prototypes -Wundef -Winit-self -Wpointer-arith -Wshadow -Wsign-promo -Wuninitialized -Winconsistent-missing-override -Wno-delete-non-virtual-dtor -Wno-unnamed-type-template-args -Wno-comment -Wno-deprecated-enum-enum-conversion -Wno-deprecated-anon-enum-enum-conversion -fdiagnostics-show-option -Qunused-arguments -ffunction-sections -fdata-sections    -fvisibility=hidden -fvisibility-inlines-hidden -fno-limit-debug-info   -O0 -DDEBUG -D_DEBUG
--     Linker flags (Release):      -Wl,--build-id=sha1 -Wl,--no-rosegment -Wl,--no-undefined-version -Wl,--fatal-warnings -Wl,--no-undefined -Qunused-arguments   -Wl,--gc-sections -Wl,--as-needed -Wl,--no-undefined -Wl,--gc-sections
--     Linker flags (Debug):        -Wl,--build-id=sha1 -Wl,--no-rosegment -Wl,--no-undefined-version -Wl,--fatal-warnings -Wl,--no-undefined -Qunused-arguments   -Wl,--gc-sections -Wl,--as-needed -Wl,--no-undefined
--     ccache:                      NO
--     Precompiled headers:         NO
--     Extra dependencies:          dl m log
--     3rdparty dependencies:
--
--   OpenCV modules:
--     To be built:                 calib3d core dnn features2d flann gapi highgui imgcodecs imgproc ml objdetect photo stitching ts video videoio 
--     Disabled:                    world
--     Disabled by dependency:      -
--     Unavailable:                 java python2 python3
--     Applications:                tests perf_tests
--     Documentation:               NO
--     Non-free algorithms:         NO
--
--   Android NDK:                   G:/SDK/ndk/26.0.10792818 (ver 26.0.10792818)
--     Android ABI:                 arm64-v8a
--     NDK toolchain:               aarch64-linux-android-clang
--     STL type:                    c++_shared
--     Native API level:            21
--   Android SDK:                   not used, projects are not built
-- 
--   GUI:                           NONE
--
--   Media I/O:
--     ZLib:                        z (ver 1.2.13)
--     JPEG:                        build-libjpeg-turbo (ver 3.0.3-70)
--       SIMD Support Request:      YES
--       SIMD Support:              YES
--     WEBP:                        build (ver encoder: 0x020f)
--     PNG:                         build (ver 1.6.43)
--       SIMD Support Request:      YES
--       SIMD Support:              YES (Arm NEON)
--     TIFF:                        build (ver 42 - 4.6.0)
--     JPEG 2000:                   build (ver 2.5.0)
--     OpenEXR:                     build (ver 2.3.0)
--     HDR:                         YES
--     SUNRASTER:                   YES
--     PXM:                         YES
--     PFM:                         YES
--
--   Video I/O:
--    MEDIANDK:                     YES
--    NDK Camera:                   NO
--
--   Parallel framework:            pthreads
--
--   Trace:                         YES (with Intel ITT)
--
--   Other third-party libraries:
--     Custom HAL:                  YES (carotene (ver 0.0.1, Auto detected))
--     Protobuf:                    build (3.19.1)
--     Flatbuffers:                 builtin/3rdparty (23.5.9)
--
--   Python (for build):            G:/Python3.11/python.exe
--
--   Install to:                    G:/opencv-4.10.0_so/arm64-v8a_build/install
-- -----------------------------------------------------------------
--
-- Configuring done (56.9s)
-- Generating done (2.2s)
-- Build files have been written to: G:/opencv-4.10.0_so/arm64-v8a_build

安装

ninja install

安装目录

V7a同理

其他

指定输出目录
-DCMAKE_INSTALL_PREFIX=

集成到Android Studio

目录结构如下

build_gradle

apply plugin: 'com.android.application'

android {
    compileSdkVersion rootProject.ext.compileSdkVersion
    buildToolsVersion rootProject.ext.buildToolsVersion
    defaultConfig {
        applicationId "com.guide.opengllib"
        minSdkVersion rootProject.ext.minSdkVersion
        targetSdkVersion rootProject.ext.targetSdkVersion
        versionCode rootProject.ext.versionCode
        versionName rootProject.ext.versionName

        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"

        ndk {
            abiFilters /*"armeabi-v7a"*/"arm64-v8a"
        }

        externalNativeBuild {
            cmake {
                cppFlags ""
                // 检查是否有正确引入C++ 相关的库依赖，比如
                arguments "-DANDROID_STL=c++_shared"
            }
        }
    }
    lintOptions {
        abortOnError false
    }

    externalNativeBuild {
        cmake {
            path "CMakeLists.txt"
        }
    }
    sourceSets {
        main {
            jniLibs.srcDirs = ['src/main/cpp/libs']
        }
    }

    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
    }

}

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])

    implementation "androidx.appcompat:appcompat:$rootProject.ext.appcompatVersion"
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'androidx.test:runner:1.1.1'
    androidTestImplementation "androidx.test.espresso:espresso-core:3.2.0"
}

CmakeList.txt

 cmake_minimum_required(VERSION 3.4.1)
set(libname opencv_guidecore)

add_definitions("-D__STDC_CONSTANT_MACROS")

set(OpenCVHome ${CMAKE_SOURCE_DIR}/src/main/cpp)

include_directories(${OpenCVHome}/jni/include)

# 设置 STL 库
set(ANDROID_STL c++_shared)

# 设置 OpenCV 库路径
set(OpenCV_LIB_PATH ${OpenCVHome}/libs/${ANDROID_ABI})  # 根据实际路径设置

message(STATUS "OpenCV_LIB_PATH: ${OpenCV_LIB_PATH}")

add_library(opencv_imgproc
        SHARED
        IMPORTED)
set_target_properties(opencv_imgproc
        PROPERTIES IMPORTED_LOCATION
        ${OpenCV_LIB_PATH}/libopencv_imgproc.so)

add_library(opencv_core
        SHARED
        IMPORTED)
set_target_properties(opencv_core
        PROPERTIES IMPORTED_LOCATION
        ${OpenCV_LIB_PATH}/libopencv_core.so)

add_library(opencv_video
        SHARED
        IMPORTED)
set_target_properties(opencv_video
        PROPERTIES IMPORTED_LOCATION
        ${OpenCV_LIB_PATH}/libopencv_video.so)


add_library(opencv_imgcodecs
        SHARED
        IMPORTED)
set_target_properties(opencv_imgcodecs
        PROPERTIES IMPORTED_LOCATION
        ${OpenCV_LIB_PATH}/libopencv_imgcodecs.so)


file(GLOB SRC_FILES
        ${OpenCVHome}/*.cpp
        )

add_library( # Sets the name of the library.
        ${libname}
        SHARED
        ${SRC_FILES}
        )

find_library(log-lib log)

# 链接 OpenCV 的 .so 文件
target_link_libraries(
        ${libname}
        android
        ${log-lib}
        opencv_imgproc
        opencv_core
        opencv_video
        opencv_imgcodecs
)

JNI源码

#include <jni.h>
#include <opencv2/opencv.hpp>
#include <opencv2/imgproc.hpp>  // 引入图像处理模块
#include <opencv2/core.hpp>     // 引入核心模块
#include "opencv_guidecore.h"
#include <android/log.h>

#define LOG_TAG "NativeLib"
#define LOGI(...)  __android_log_print(ANDROID_LOG_INFO, LOG_TAG, __VA_ARGS__)


extern "C"
JNIEXPORT void JNICALL
Java_com_guide_opengllib_MainGlActivity_processImage(JNIEnv *env, jobject thiz, jstring input_image_path, jstring output_image_path) {
    // 获取传递的图像路径字符串
    const char *input_path = env->GetStringUTFChars(input_image_path, nullptr);
    const char *output_path = env->GetStringUTFChars(output_image_path, nullptr);

    // 使用 OpenCV 读取图像
    cv::Mat image = cv::imread(input_path);
    if (image.empty()) {
        LOGI("Could not open or find the image!");
        return;
    }

    // 转换为灰度图像
    cv::Mat gray_image;
    cv::cvtColor(image, gray_image, cv::COLOR_BGR2GRAY);

    // 保存处理后的图像
    cv::imwrite(output_path, gray_image);

    // 释放资源
    env->ReleaseStringUTFChars(input_image_path, input_path);
    env->ReleaseStringUTFChars(output_image_path, output_path);

    LOGI("Image processed and saved to %s", output_path);
}

Activity中

static {
    System.loadLibrary("opencv_guidecore");  // 加载生成的 .so 库
}

// 声明本地方法
public native void processImage(String inputImagePath, String outputImagePath);

//实例3
findViewById(R.id.test3).setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {
        processImage("", "");
    }
});

打印日志

集成第三方去噪点算法
https://github.com/Linwei-Chen/NL-means/blob/master/main.cpp