1
对不起,在对象中可能看起来有点通用,但我没有与Android NDK开发经验,我试图将Java方法转换为本机代码,我遇到一些问题。Android NDK,JNI代码不工作和相关的疑惑
最初的Java代码不是我的,而是取自一个开源库。
我有这样的感觉,我正在做一些与内存有关的错误以及处理对象的方式。
i_out是和从Java传入并在其中我从本地方法中设置一些值的对象。
这是在Android Java代码中定义的方法签名:
private native int nativeXLineToRle(int i_x, int i_y, int i_len, int i_th, NyARLabeling_Rle.RleElement[] i_out, byte[] buffer, int width);
这是精细地与NDK建造编译的代码:
#include <jni.h>
JNIEXPORT jint JNICALL Java_jp_androidgroup_nyartoolkit_utils_NyARRlePixelDriverYUV420Reader_nativeXLineToRle(JNIEnv * env, jint i_x, jint i_y, jint i_len, jint i_th, jobjectArray i_out, jbyteArray buffer, jint width)
{
int current = 0;
int r = -1;
int st = i_x + width*i_y;
int x = st;
int right_edge = st + i_len - 1;
jobject anRleElement = (*env)->GetObjectArrayElement(env, i_out, 0);
jclass rleElementClass = (*env)->GetObjectClass(env, anRleElement);
jfieldID lFid = (*env)->GetFieldID(env, rleElementClass, "l", "I");
jfieldID rFid = (*env)->GetFieldID(env, rleElementClass, "r", "I");
jobject currentRleElement;
jbyte* buf = buffer;
while (x < right_edge) {
if (buf[x] > i_th) {
x++;
continue;
}
r = (x - st);
currentRleElement = (*env)->GetObjectArrayElement(env, i_out, current);
(*env)->SetIntField(env, currentRleElement, lFid, r);
r++;
x++;
while (x < right_edge) {
if (buf[x] > i_th) {
(*env)->SetIntField(env, currentRleElement, rFid, r);
current++;
x++;
r = -1;
break;
} else {
r++;
x++;
}
}
}
currentRleElement = (*env)->GetObjectArrayElement(env, i_out, current);
if (buf[x] > i_th) {
if (r >= 0) {
(*env)->SetIntField(env, currentRleElement, rFid, r);
current++;
currentRleElement = (*env)->GetObjectArrayElement(env, i_out, current);
}
} else {
if (r >= 0) {
(*env)->SetIntField(env, currentRleElement, rFid, r+1);
} else {
(*env)->SetIntField(env, currentRleElement, lFid, i_len-1);
(*env)->SetIntField(env, currentRleElement, rFid, i_len);
}
current++;
}
return current;
}
上的Android 2.3运行代码.3设备logcat显示以下内容:
"Signal Catcher" daemon prio=5 tid=4 RUNNABLE
| group="system" sCount=0 dsCount=0 obj=0x4050d430 self=0x119b78
| sysTid=2343 nice=0 sched=0/0 cgrp=default handle=2511112
at dalvik.system.NativeStart.run(Native Method)
"GLThread" prio=5 tid=12 RUNNABLE
| group="main" sCount=1 dsCount=0 obj=0x40532180 self=0x2b7c20
| sysTid=2356 nice=0 sched=0/0 cgrp=default handle=2850136
at jp.androidgroup.nyartoolkit.utils.NyARRlePixelDriverYUV420Reader.nativeXLineToRle(Native Method)
at jp.androidgroup.nyartoolkit.utils.NyARRlePixelDriverYUV420Reader.xLineToRle(NyARAndYUV420GsRaster.java:268)
..............
at com.badlogic.gdx.backends.android.surfaceview.GLSurfaceViewCupcake$GLThread.run(GLSurfaceViewCupcake.java:646)
而一个的Android 4.1.2设备上我得到如下:
E/dalvikvm(3443): JNI ERROR (app bug): accessed stale weak global reference 0x7f (index 31 in a table of size 0)
E/dalvikvm(3443): VM aborting
A/libc(3443): Fatal signal 11 (SIGSEGV) at 0xdeadd00d (code=1), thread 3544 (Thread-36107)
现在我很卡住所以任何帮助将是非常赞赏。 在此先感谢
弗朗西斯