frequent SIGSEGV crashes when adding OnFrameAvailableListener to example application

[joep27182]

I noticed that adding an empty OnFrameAvailableListenerto the Tango service frequently causes a SIGSEGVcrash when a lifecycle transition happens (i.e. onPause() / onResume() etc.). This is quite a problem for me since I need to perform operations on image data itself using OpenCV. If someone has a workaround for accessing raw image data without crashes, please let me know.

Steps to reproduce:

• add the following code at the end of setTangoListeners() in the java_augmented_reality_exampleproject:

mTango.experimentalConnectOnFrameListener(TangoCameraIntrinsics.TANGO_CAMERA_COLOR, new Tango.OnFrameAvailableListener() {
    @Override
    public void onFrameAvailable(TangoImageBuffer tangoImageBuffer, int i) {

    }
});

• launch the app, trigger some lifecycle events by switching back and forth between android and the app

Logcat:

10-02 21:03:54.656 31675-31675/com.projecttango.experiments.augmentedrealitysample I/tango-client-api-jni: DisconnectTexture context 0x4b0cc0f0, camera 0
10-02 21:03:54.656 31675-31675/com.projecttango.experiments.augmentedrealitysample I/tango_client_api: TangoErrorType TangoService_disconnectCamera(TangoCameraId): Disconnecting camera_id = 0...
10-02 21:03:54.656 31675-31675/com.projecttango.experiments.augmentedrealitysample I/tango_client_api: TangoErrorType TangoService_disconnectCamera(TangoCameraId): Done disconnecting camera.
10-02 21:03:54.656 31675-31675/com.projecttango.experiments.augmentedrealitysample I/tango_client_api: void TangoService_disconnect(): Disconnecting from Tango...

Backtrace:

(lldb) bt
* thread #13: tid = 31692, 0x4b088ee0 libtango_client_api.so`Tango::TangoGraphicBuffer::unlock() const + 8, name = 'Binder_2', stop reason = signal SIGSEGV: invalid address (fault address: 0x44)
    frame #0: 0x4b088ee0 libtango_client_api.so`Tango::TangoGraphicBuffer::unlock() const + 8
    frame #1: 0x4b077df2 libtango_client_api.so`TangoListener::onGraphicBufferAvailable(android::sp<Tango::TangoGraphicBuffer> const&) + 162
    frame #2: 0x4b084722 libtango_client_api.so`Tango::ClientListener::onTransact(unsigned int, android::Parcel const&, android::Parcel*, unsigned int) + 446
    frame #3: 0x401cb226 libbinder.so`android::BBinder::transact(unsigned int, android::Parcel const&, android::Parcel*, unsigned int) + 62
    frame #4: 0x401cf79a libbinder.so`android::IPCThreadState::executeCommand(int) + 510
    frame #5: 0x401cfb1a libbinder.so`android::IPCThreadState::getAndExecuteCommand() + 42
    frame #6: 0x401cfb90 libbinder.so`android::IPCThreadState::joinThreadPool(bool) + 52
    frame #7: 0x401d39ac libbinder.so
    frame #8: 0x4019ea5a libutils.so`android::Thread::_threadLoop(void*) + 218
    frame #9: 0x4022beb2 libandroid_runtime.so`android::AndroidRuntime::javaThreadShell(void*) + 70
    frame #10: 0x4019e58c libutils.so
    frame #11: 0x401231b4 libc.so`__thread_entry + 76
  * frame #12: 0x4012334c libc.so`pthread_create + 244

Version Info:

Both Tango Core and TangoRelaseLibs / Tango Examples are at relase version "Vega".