当我将appcompat_v7_4作为库项目添加到我的android项目时，我的应用程序试图在armeabi-v7a文件夹中找到本机库，但我只有armeabi文件夹。然后应用程序崩溃，因为无法找到本机库。我创建了armeabi-v7a文件夹，并将armeabi文件夹内容复制到armeabi-v7a文件夹，并且应用程序没有崩溃。 appcompat_v7_4与armeabi-v7a的关系是什么？
堆栈跟踪如下：
java.lang.NoClassDefFoundError: java.lang.ClassNotFoundException: com.googlecode.javacv.cpp.avcodec
at com.googlecode.javacpp.Loader.load(Loader.java:455)
at com.googlecode.javacv.cpp.avformat.<clinit>(avformat.java:76)
at com.butterfly.recorder.FFmpegFrameRecorder.<init>(FFmpegFrameRecorder.java:231)
at com.butterfly.RecordActivity.createRecorder(RecordActivity.java:329)
at com.butterfly.RecordActivity.initRecorder(RecordActivity.java:314)
at com.butterfly.RecordActivity.onClick(RecordActivity.java:518)
at android.view.View.performClick(View.java:4438)
at android.view.View$PerformClick.run(View.java:18422)
at android.os.Handler.handleCallback(Handler.java:733)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:136)
at android.app.ActivityThread.main(ActivityThread.java:5017)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.ClassNotFoundException: com.googlecode.javacv.cpp.avcodec
at java.lang.Class.classForName(Native Method)
at java.lang.Class.forName(Class.java:251)
at com.googlecode.javacpp.Loader.load(Loader.java:453)
... 16 more
Caused by: java.lang.UnsatisfiedLinkError: Couldn't load jniavcodec from loader dalvik.system.PathClassLoader[DexPathList[[zip file "/data/app/com.butterfly-2.apk"],nativeLibraryDirectories=[/data/app-lib/com.butterfly-2, /vendor/lib, /system/lib]]]: findLibrary returned null
at java.lang.Runtime.loadLibrary(Runtime.java:358)
at java.lang.System.loadLibrary(System.java:526)
at com.googlecode.javacpp.Loader.loadLibrary(Loader.java:593)
at com.googlecode.javacpp.Loader.load(Loader.java:489)
at com.googlecode.javacpp.Loader.load(Loader.java:431)
at com.googlecode.javacv.cpp.avcodec.<clinit>(avcodec.java:86)
... 19 more
Caused by: java.lang.UnsatisfiedLinkError: Couldn't load avcodec from loader dalvik.system.PathClassLoader[DexPathList[[zip file "/data/app/com.butterfly-2.apk"],nativeLibraryDirectories=[/data/app-lib/com.butterfly-2, /vendor/lib, /system/lib]]]: findLibrary returned null
at java.lang.Runtime.loadLibrary(Runtime.java:358)
at java.lang.System.loadLibrary(System.java:526)
at com.googlecode.javacpp.Loader.loadLibrary(Loader.java:593)
at com.googlecode.javacpp.Loader.load(Loader.java:481)
... 21 more