android opencv图像处理,Android 引入图像处理库OpenCV

这里省去ndk开发环境的配置 直接进入opencv集成到Android studio中

我们在opencv官网下载到的https://opencv.org android开发包 解压压缩包结构

U$MD9(`)]]TK6WHT8H`O470.png

在项目的main文件下新建jniLibs目录 将opencv的.so文件拷贝到该目录下

ss.png

将opencv的include文件夹拷贝到cpp文件夹下

includ.png

配置cmake文件

# 设置include文件夹的地址

include_directories(${CMAKE_SOURCE_DIR}/src/main/cpp/include)

# 设置opencv的动态库

add_library(libopencv_java3

SHARED

IMPORTED)

set_target_properties(libopencv_java3

PROPERTIES

IMPORTED_LOCATION ${CMAKE_SOURCE_DIR}/src/main/jniLibs/${ANDROID_ABI}/libopencv_java3.so)

target_link_libraries( # Specifies the target library.

native-lib libopencv_java3 jnigraphics

# Links the target library to the log library

# included in the NDK.

${log-lib})

build.gradle文件 android 节点下配置

android {

.......

sourceSets {

main {

jniLibs.srcDirs = ['src/main/jniLibs']

}

}

.......

到此我们opencv 已经配置完成 下面我们来写一个小demo验证是否配置成功

public class MainActivity extends AppCompatActivity {

// Used to load the 'native-lib' library on application startup.

static {

System.loadLibrary("native-lib");

}

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

ImageView iv_show = findViewById(R.id.iv_show);

Bitmap bitmap = BitmapFactory.decodeResource(getResources(), R.mipmap.zyz);

BitmapUtils.counterWorld(bitmap);

iv_show.setImageBitmap(bitmap);

}

}

下面是利用opencv 实现的一个逆世界效果

#include

#include

#include

#include "bitmap/com_youyangbo_opencv_BitmapUtils.h"

#include "bitmap/opencvHelp.h"

using namespace cv;

extern "C" void JNICALL Java_com_youyangbo_opencv_BitmapUtils_counterWorld

(JNIEnv *env, jclass jclazz, jobject bitmap) {

Mat src;

bitmap2Mat(env, src, bitmap);

int middleRows = src.rows >> 1;

int quarterRows = middleRows >> 1;

Mat conword_imag(src.size(), src.type());

for (int row = 0; row < middleRows; ++row) {

for (int col = 0; col < src.cols; ++col) {

conword_imag.at(middleRows + row, col) = src.at(

quarterRows + row, col);

}

}

for (int row = 0; row < middleRows; ++row) {

for (int col = 0; col < src.cols; ++col) {

conword_imag.at(middleRows - row, col) = src.at(quarterRows + row, col);

}

}

mat2Bitmap(env, conword_imag, bitmap);

}

opencv 是c/c++的库，处理图片数据是Mat(矩阵)，Android 图片表现形式是Bitmap,所以Android中的图片交给opencv处理必须先将Bitmap转化成Mat，

#include "bitmap/opencvHelp.h"

#include

/**

* bitmap 转化为矩阵(Mat)

* @param pEnv

* @param mat

* @param bitmap

*/

void bitmap2Mat(JNIEnv *env, cv::Mat &mat, jobject bitmap) {

AndroidBitmapInfo bitmap_info;

void *pPixel = NULL;

AndroidBitmap_getInfo(env, bitmap, &bitmap_info);

AndroidBitmap_lockPixels(env, bitmap, &pPixel);

//判断传入的图片是什么类型

if (bitmap_info.format == ANDROID_BITMAP_FORMAT_RGBA_8888) {//32

//对应opncv Mat 类型 CV_8UC4

cv::Mat temp(bitmap_info.height, bitmap_info.width, CV_8UC4, pPixel);

temp.copyTo(mat);

} else if (bitmap_info.format == ANDROID_BITMAP_FORMAT_RGB_565) {//16

//对应opncv Mat 类型 CV_8UC2

cv::Mat temp(bitmap_info.height, bitmap_info.width, CV_8UC2, pPixel);

cv::cvtColor(temp, mat, CV_BGRA2BGR565);

}

AndroidBitmap_unlockPixels(env, bitmap);

}

/**

* Mat转化为Bitmap

* @param pEnv

* @param mat

* @param bitmap

*/

void mat2Bitmap(JNIEnv *env, cv::Mat &mat, jobject bitmap) {

AndroidBitmapInfo bitmap_info;

void *pPixel = NULL;

AndroidBitmap_lockPixels(env, bitmap, &pPixel);

AndroidBitmap_getInfo(env, bitmap, &bitmap_info);

//判断传入的图片是什么类型

if (bitmap_info.format == ANDROID_BITMAP_FORMAT_RGBA_8888) {//32

cv::Mat tmp(bitmap_info.height, bitmap_info.width, CV_8UC4, pPixel);

//对应opncv Mat 类型 CV_8UC4

if (mat.type() == CV_8UC4) {

//对应bitmap RGBA_8888

mat.copyTo(tmp);

} else if (mat.type() == CV_8UC2) {

//对应bitmap RGB_565

cv::cvtColor(mat, tmp, CV_BGR5652BGRA);

} else if (mat.type() == CV_8UC1) {

//单通道 0-255 的灰度图

cv::cvtColor(mat, tmp, CV_GRAY2BGRA);

}

} else if (bitmap_info.format == ANDROID_BITMAP_FORMAT_RGB_565) {//16

cv::Mat tmp(bitmap_info.height, bitmap_info.width, CV_8UC2, pPixel);

//对应opncv Mat 类型 CV_8UC2

if (mat.type() == CV_8UC4) {

//对应bitmap RGBA_8888

cv::cvtColor(mat, tmp, CV_BGRA2BGR565);

} else if (mat.type() == CV_8UC2) {

//对应bitmap RGB_565

mat.copyTo(tmp);

} else if (mat.type() == CV_8UC1) {

//单通道 0-255 的灰度图

cv::cvtColor(mat, tmp, CV_GRAY2BGR565);

}

}

AndroidBitmap_unlockPixels(env, bitmap);

}

代码运行效果：

原图：

2.jpg

经过opencv处理过的

demo.png