我正在尝试使用基于AOSP的类（如Camera.h）来NDK访问摄像头，如所描述http://guoh.org/lifelog/2013/05/android-camera-architecture/
static int android_hardware_Camera_native_setup(JNIEnv *env, jobject thiz, jobject weak_this, jint cameraId)
{
sp<Camera> camera = Camera::connect(cameraId);
if (camera == NULL) {
// jniThrowRuntimeException(env, "Fail to connect to camera service");
return 1; // always comes here
}
...}
logcat是：
01-02 08:19:11.870 1351-1649/? I/CameraClient﹕ Opening camera 0
01-02 08:19:13.110 1351-1649/? D/HALCameraFactory﹕ Calling process is: com.my.camndkapp
01-02 08:19:13.110 3741-3741/com.my.camndkapp W/dalvikvm﹕ JNI WARNING: instance fieldID 0x0 not valid for class Ljava/lang/Class;
01-02 08:19:13.110 3741-3741/com.my.camndkapp W/dalvikvm﹕ in Lcom/my/camndkapp/CameraGate;.initCamera:(Ljava/lang/Object;I)I (SetIntField)
01-02 08:19:13.110 3741-3741/com.my.camndkapp I/dalvikvm﹕ "main" prio=5 tid=1 RUNNABLE
01-02 08:19:13.110 3741-3741/com.my.camndkapp I/dalvikvm﹕ | group="main" sCount=0 dsCount=0 obj=0x40b129a0 self=0x56a5c010
01-02 08:19:13.110 3741-3741/com.my.camndkapp I/dalvikvm﹕ | sysTid=3741 nice=0 sched=0/0 cgrp=apps handle=1074443228
01-02 08:19:13.110 3741-3741/com.my.camndkapp I/dalvikvm﹕ | state=R schedstat=( 0 0 0 ) utm=25 stm=10 core=1
01-02 08:19:13.110 3741-3741/com.my.camndkapp I/dalvikvm﹕ at com.my.camndkapp.CameraGate.initCamera(Native Method)
01-02 08:19:13.110 3741-3741/com.my.camndkapp I/dalvikvm﹕ at com.my.camndkapp.CameraGate.init(CameraGate.java:34)
01-02 08:19:13.110 3741-3741/com.my.camndkapp I/dalvikvm﹕ at com.my.camndkapp.FullscreenActivity.onCreate(FullscreenActivity.java:73)
01-02 08:19:13.110 3741-3741/com.my.camndkapp I/dalvikvm﹕ at android.app.Activity.performCreate(Activity.java:5104)
01-02 08:19:13.110 3741-3741/com.my.camndkapp I/dalvikvm﹕ at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1080)
01-02 08:19:13.110 3741-3741/com.my.camndkapp I/dalvikvm﹕ at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2144)
01-02 08:19:13.110 3741-3741/com.my.camndkapp I/dalvikvm﹕ at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2230)
01-02 08:19:13.110 3741-3741/com.my.camndkapp I/dalvikvm﹕ at android.app.ActivityThread.access$600(ActivityThread.java:141)
01-02 08:19:13.120 3741-3741/com.my.camndkapp I/dalvikvm﹕ at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1234)
01-02 08:19:13.120 3741-3741/com.my.camndkapp I/dalvikvm﹕ at android.os.Handler.dispatchMessage(Handler.java:99)
01-02 08:19:13.120 3741-3741/com.my.camndkapp I/dalvikvm﹕ at android.os.Looper.loop(Looper.java:137)
01-02 08:19:13.120 3741-3741/com.my.camndkapp I/dalvikvm﹕ at android.app.ActivityThread.main(ActivityThread.java:5041)
01-02 08:19:13.120 3741-3741/com.my.camndkapp I/dalvikvm﹕ at java.lang.reflect.Method.invokeNative(Native Method)
01-02 08:19:13.120 3741-3741/com.my.camndkapp I/dalvikvm﹕ at java.lang.reflect.Method.invoke(Method.java:511)
01-02 08:19:13.120 3741-3741/com.my.camndkapp I/dalvikvm﹕ at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:817)
01-02 08:19:13.120 3741-3741/com.my.camndkapp I/dalvikvm﹕ at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:584)
01-02 08:19:13.120 3741-3741/com.my.camndkapp I/dalvikvm﹕ at dalvik.system.NativeStart.main(Native Method)
01-02 08:19:13.120 3741-3741/com.my.camndkapp I/dalvikvm﹕ [ 01-02 08:19:13.120 3741: 3741 E/dalvikvm ]
VM aborting
01-02 08:19:13.120 3741-3741/com.my.camndkapp A/libc﹕ Fatal signal 11 (SIGSEGV) at 0xdeadd00d (code=1), thread 3741 (my.camndkapp)
注1：如果我将 -lcamera.fiber.so 添加到Android.mk中的库中 - 应用程序在启动时崩溃
注2：所有权限都存在，Java的Camera.open（）工作正常
注3：我想知道Camera :: connect（..）原则上如何返回NULL：
sp<Camera> Camera::connect(int cameraId)
{
ALOGV("connect");
sp<Camera> c = new Camera();
const sp<ICameraService>& cs = getCameraService();
if (cs != 0) {
c->mCamera = cs->connect(c, cameraId);
}
if (c->mCamera != 0) {
c->mCamera->asBinder()->linkToDeath(c);
c->mStatus = NO_ERROR;
} else {
c.clear();
}
return c;
}
如果 c = new Camera（）返回NULL，它将在下一行访问任何 c-＆gt; var
时崩溃注4： Android级API-17
提前谢谢你！
编辑1：同时对getNumberOfCameras（）的本机调用正常工作：
static jint android_hardware_Camera_getNumberOfCameras(JNIEnv *env, jobject thiz)
{
return Camera::getNumberOfCameras();
}