我创建了这个 Android 应用程序：
MainActivity.java：
package com.example.provavideocapture;
import android.os.Bundle;
import android.app.Activity;
public class MainActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
videocapturing();
}
static{
System.loadLibrary("opencv_java");
System.load("videocapture");
}
public native long videocapturing();
}
安卓.mk
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
OPENCV_LIB_TYPE:=STATIC
include C:\Users\Usr\Desktop\Android\OpenCV-2.4.5-android-sdk\sdk\native\jni\OpenCV.mk
LOCAL_MODULE := videocapture
LOCAL_C_INCLUDES += $(LOCAL_PATH)
LOCAL_LDLIBS += -llog -ldl
LOCAL_SRC_FILES := jniVideoCapture.cpp
include $(BUILD_SHARED_LIBRARY)
jniVideoCapture.cpp
#include <jni.h>
#include <GLES/gl.h>
#include <GLES/glext.h>
#include <android/log.h>
#include <opencv2/highgui/highgui.hpp>
#include <opencv/cv.h>
#include <opencv2/opencv.hpp>
using namespace cv;
extern "C" {
JNIEXPORT jint JNICALL Java_com_example_provavideocapture_MainActivity_videocapturing(JNIEnv*, jobject)
{
VideoCapture cap(0);
if(!cap.isOpened())
return -1;
Mat edges;
namedWindow("edges",CV_WINDOW_AUTOSIZE);
for(;;){
Mat frame;
cap>>frame;
cvtColor(frame,edges,CV_BGR2GRAY);
GaussianBlur(edges,edges,Size(7,7),1.5,1.5);
Canny(edges,edges,0,30,3);
imshow("edges",edges);
if(waitKey(30)>=30) break;
}
return 0;
}
}
应用程序.mk
APP_ABI := all
APP_STL := gnustl_static
APP_CPPFLAGS := -frtti -fexceptions
APP_PLATFORM := android-9
清单.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.provavideocapture"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="10"
android:targetSdkVersion="17" />
<uses-permission android:name="android.permission.CAMERA" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-feature android:name="android.hardware.camera.any" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name="com.example.provavideocapture.MainActivity"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
我有这个错误（在logcat中）：
05-17 12:45:34.095: E/AndroidRuntime(30365): FATAL EXCEPTION: main
05-17 12:45:34.095: E/AndroidRuntime(30365): java.lang.ExceptionInInitializerError
05-17 12:45:34.095: E/AndroidRuntime(30365): at java.lang.Class.newInstanceImpl(Native Method)
05-17 12:45:34.095: E/AndroidRuntime(30365): at java.lang.Class.newInstance(Class.java:1319)
05-17 12:45:34.095: E/AndroidRuntime(30365): at android.app.Instrumentation.newActivity(Instrumentation.java:1071)
05-17 12:45:34.095: E/AndroidRuntime(30365): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2163)
05-17 12:45:34.095: E/AndroidRuntime(30365): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2296)
05-17 12:45:34.095: E/AndroidRuntime(30365): at android.app.ActivityThread.access$700(ActivityThread.java:151)
05-17 12:45:34.095: E/AndroidRuntime(30365): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1281)
05-17 12:45:34.095: E/AndroidRuntime(30365): at android.os.Handler.dispatchMessage(Handler.java:99)
05-17 12:45:34.095: E/AndroidRuntime(30365): at android.os.Looper.loop(Looper.java:137)
05-17 12:45:34.095: E/AndroidRuntime(30365): at android.app.ActivityThread.main(ActivityThread.java:5293)
05-17 12:45:34.095: E/AndroidRuntime(30365): at java.lang.reflect.Method.invokeNative(Native Method)
05-17 12:45:34.095: E/AndroidRuntime(30365): at java.lang.reflect.Method.invoke(Method.java:511)
05-17 12:45:34.095: E/AndroidRuntime(30365): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1102)
05-17 12:45:34.095: E/AndroidRuntime(30365): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:869)
05-17 12:45:34.095: E/AndroidRuntime(30365): at dalvik.system.NativeStart.main(Native Method)
05-17 12:45:34.095: E/AndroidRuntime(30365): Caused by: java.lang.UnsatisfiedLinkError: Couldn't load opencv_java from loader dalvik.system.PathClassLoader[dexPath=/data/app/com.example.provavideocapture-1.apk,libraryPath=/data/app-lib/com.example.provavideocapture-1]: findLibrary returned null
05-17 12:45:34.095: E/AndroidRuntime(30365): at java.lang.Runtime.loadLibrary(Runtime.java:365)
05-17 12:45:34.095: E/AndroidRuntime(30365): at java.lang.System.loadLibrary(System.java:535)
05-17 12:45:34.095: E/AndroidRuntime(30365): at com.example.provavideocapture.MainActivity.<clinit>(MainActivity.java:17)
我该如何解决这个问题？我正在使用适用于 android 版本 2.4.5 的 opencv 开发 Eclipse Juno。