Develop Reference

Android NDK/JNI UnsatisfiedLinkError With .So library

I'm new to Android NDK, and I'm currently trying to build a RTMP C client for Android (and later iOS). Currently, I'm running into an issue where the application crashes as soon as I try to load my library:
static {
System.loadLibrary("test");
}
The exception I get is
java.lang.UnsatisfiedLinkError: dlopen failed: could not load library "librtmp.so.1" needed by "libtest.so"; caused by library "librtmp.so.1" not found
I'm honestly completely lost. ndk-build doesn't return any errors:
[armeabi] Prebuilt : rtmp.so <= jni/rtmp/
[armeabi] Install : rtmp.so => libs/armeabi/rtmp.so
[armeabi] Compile thumb : test <= RTMPClient.c
[armeabi] SharedLibrary : libtest.so
[armeabi] Install : libtest.so => libs/armeabi/libtest.so
I've tried loading in the rtmp librarary via System.loadLibrary("rtmp"), but no dice.
Android.mk
LOCAL_PATH:= $(call my-dir)
LIBS_PATH := libs/$(TARGET_ARCH_ABI)
include $(CLEAR_VARS)
LOCAL_MODULE := rtmp
LOCAL_SRC_FILES := rtmp/rtmp.so
LOCAL_C_INCLUDES := rtmp/
include $(PREBUILT_SHARED_LIBRARY)
include $(CLEAR_VARS)
LOCAL_MODULE := test
LOCAL_SRC_FILES := RTMPClient.c
LOCAL_LDLIBS := -llog
LOCAL_SHARED_LIBRARIES += rtmp
include $(BUILD_SHARED_LIBRARY)
Application.mk
APP_PLATFORM:=android-19
My RTMPClient.c uses some structs and functions from rtmp like so:
#include <rtmp/rtmp.h>
I'm not sure where librtmp.so.1 is coming from, but I also found it in my libtest.so with arm-linux-andrioideabi-readelf:
0x00000001 (NEEDED) Shared library: [librtmp.so.1]
Any ideas on how I can fix this?
EDIT: I got the rtmp.so file from here. I was sent there from the KODI librtmp update page

I ended up throwing out my rtmp.so file, and instead grabbed the jni files from rtmpdump-android. After putting those file in, changing my android.mk file to:
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_SRC_FILES += \
librtmp/amf.c \
librtmp/hashswf.c \
librtmp/log.c \
librtmp/parseurl.c \
librtmp/rtmp.c
LOCAL_CFLAGS := -D__STDC_CONSTANT_MACROS -DNO_CRYPTO
LOCAL_LDLIBS := -llog
LOCAL_MODULE := librtmp
include $(BUILD_STATIC_LIBRARY)
include $(CLEAR_VARS)
LOCAL_MODULE := dump
LOCAL_CFLAGS := -DRTMPDUMP_VERSION=\"v2.4\"
LOCAL_LDLIBS := -llog
LOCAL_SRC_FILES := dump/rtmpdump.c
LOCAL_C_INCLUDES := $(LOCAL_PATH)/../librtmp
LOCAL_C_INCLUDES += dump/rtmpdump.h
LOCAL_STATIC_LIBRARIES := librtmp
include $(BUILD_SHARED_LIBRARY)
include $(CLEAR_VARS)
LOCAL_MODULE := test
LOCAL_SRC_FILES := nelly.c nelly_tables.c RTMPClient.c
LOCAL_LDLIBS := -llog
LOCAL_SHARED_LIBRARIES += dump
include $(BUILD_SHARED_LIBRARY)
And changing my RTMPClient.c file to include #include "librtmp/rtmp.h" instead of #include <rtmp/rtmp.h>, the file compiled and ran on my device without any issues.

Adding Tesseract and Opencv to Android.mk (Android Studio)

I followed the instructions from here and added OpenCV successfully. But I've been trying to add tesseract to the Android.mk as well, for a few days now, and haven't been able to do it.
I have an android.cpp that uses tesseract so I have to include the dependency in my Android.mk . I found this post that had almost the exact problem and he solved it importing libtess.so and liblept.so files into Android.mk, but didn't explain how to do that, so I looked and found this post that shows how to link prebuilt libraries. So based on that I tried this Android.mk:
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_MODULE := liblept
LOCAL_SRC_FILES := ../libs/$(TARGET_ARCH_ABI)/liblept.so
LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)/../../../../tess-two/jni
include $(PREBUILT_SHARED_LIBRARY)
include $(CLEAR_VARS)
LOCAL_MODULE := libtess
LOCAL_SRC_FILES := ../libs/$(TARGET_ARCH_ABI)/libtess.so
LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)/../../../../tess-two/jni
include $(PREBUILT_SHARED_LIBRARY)
include $(CLEAR_VARS)
OPENCV_PACKAGE_DIR:= /Users/danielsierraf/Documents/OpenCV-2.4.10-android-sdk/sdk
OPENCV_CAMERA_MODULES := off
include $(OPENCV_PACKAGE_DIR)/native/jni/OpenCV.mk
LOCAL_MODULE := run_detection
LOCAL_SHARED_LIBRARIES := libtess
LOCAL_SRC_FILES := text_detect.cpp android.cpp
LOCAL_LDLIBS += -landroid -llog -ldl
include $(BUILD_SHARED_LIBRARY)
And got this output:
[armeabi-v7a] Prebuilt : liblept.so <= src/main/jni/../libs/armeabi-v7a/
[armeabi-v7a] Install : liblept.so => src/main/jniLibs/armeabi-v7a/liblept.so
[armeabi-v7a] Compile++ thumb: run_detection <= text_detect.cpp
In file included from src/main/jni/text_detect.h:4:0,
from src/main/jni/text_detect.cpp:10:
src/main/jni/../../../../tess-two/jni/com_googlecode_tesseract_android/src/api/baseapi.h:32:22: fatal error: platform.h: No such file or directory
#include "platform.h"
^
compilation terminated.
So I guess is not linking libtess correctly, and if you look closely, it doesn't ever install libtess.so, it looks like it installs liblept.so, and then jumps to text_detect.cpp, ignoring this part:
include $(CLEAR_VARS)
LOCAL_MODULE := libtess
LOCAL_SRC_FILES := ../libs/$(TARGET_ARCH_ABI)/libtess.so
LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)/../../../../tess-two/jni
include $(PREBUILT_SHARED_LIBRARY)
So I tried to force it to install liblept and libtess completely before proceeding by putting it in different files. So I put the last part of the file in a different Android.mk in another folder and tried include $(call all-subdir-makefiles), and then it installs libtess and liblept completely, but ignores the call all-subdir-makefiles.
new jni folder structure:
Android.mk
Application.mk
text_detect/
Android.mk
android.cpp
text_detect.cpp
text_detect.h
Android.mk
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_MODULE := liblept
LOCAL_SRC_FILES := ../libs/$(TARGET_ARCH_ABI)/liblept.so
LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)/../../../../tess-two/jni
include $(PREBUILT_SHARED_LIBRARY)
include $(CLEAR_VARS)
LOCAL_MODULE := libtess
LOCAL_SRC_FILES := ../libs/$(TARGET_ARCH_ABI)/libtess.so
LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)/../../../../tess-two/jni
include $(PREBUILT_SHARED_LIBRARY)
include $(call all-subdir-makefiles)
textdetect/Android.mk
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
OPENCV_PACKAGE_DIR:= /Users/danielsierraf/Documents/OpenCV-2.4.10-android-sdk/sdk
OPENCV_CAMERA_MODULES := off
include $(OPENCV_PACKAGE_DIR)/native/jni/OpenCV.mk
LOCAL_MODULE := run_detection
LOCAL_SHARED_LIBRARIES := libtess
LOCAL_SRC_FILES := text_detect.cpp android.cpp
LOCAL_LDLIBS += -landroid -llog -ldl
include $(BUILD_SHARED_LIBRARY)
And this is the output:
[armeabi-v7a] Prebuilt : liblept.so <= src/main/jni/../libs/armeabi-v7a/
[armeabi-v7a] Install : liblept.so => src/main/jniLibs/armeabi-v7a/liblept.so
[armeabi-v7a] Prebuilt : libtess.so <= src/main/jni/../libs/armeabi-v7a/
[armeabi-v7a] Install : libtess.so => src/main/jniLibs/armeabi-v7a/libtess.so
[armeabi] Prebuilt : liblept.so <= src/main/jni/../libs/armeabi/
[armeabi] Install : liblept.so => src/main/jniLibs/armeabi/liblept.so
[armeabi] Prebuilt : libtess.so <= src/main/jni/../libs/armeabi/
[armeabi] Install : libtess.so => src/main/jniLibs/armeabi/libtess.so
[mips] Prebuilt : liblept.so <= src/main/jni/../libs/mips/
[mips] Install : liblept.so => src/main/jniLibs/mips/liblept.so
[mips] Prebuilt : libtess.so <= src/main/jni/../libs/mips/
[mips] Install : libtess.so => src/main/jniLibs/mips/libtess.so
[x86] Prebuilt : liblept.so <= src/main/jni/../libs/x86/
[x86] Install : liblept.so => src/main/jniLibs/x86/liblept.so
[x86] Prebuilt : libtess.so <= src/main/jni/../libs/x86/
[x86] Install : libtess.so => src/main/jniLibs/x86/libtess.so
As you see it installs everything from the first Android.mk perfectly, but it never runs textdetect/Android.mk
So, what I'm I doing wrong? How can I achieve this task that seems so simple? Is there an easier way?
EDIT:
After #ph0b response I went back to my first setup and added the same LOCAL_EXPORT_C_INCLUDES as the original Makefiles (with a couple of variations adapting it to my paths), and that solved it. It couldn't find platform.h because it didn't know where to look for it.
Now, after I did this change I had a different error No such file or directory #include "com_googlecode_tesseract_android/src/api/baseapi.h" and I thought this was because it didn't compile tesseract before run_detection that depends on it. Well that wasn't the problem, it still compiles run_detection before tesseract but that wasn't the issue, it was so much simpler and I feel so stupid for having spent so much time on this error. The problem was it didn't find com_googlecode_tesseract_android/src/api/baseapi.h because I didn't provide the path for that either, so I copied com_googlecode_tesseract_android and com_googlecode_leptonica_android from tess-two and added $(LOCAL_PATH) to LOCAL_EXPORT_C_INCLUDES. This is my final solution:
jni folder structure:
Android.mk
Application.mk
text_detect.cpp
android.cpp
text_detect.h
com_googlecode_leptonica_android
com_googlecode_tesseract_android
Android.mk
LOCAL_PATH := $(call my-dir)
#leptonica
LEPTONICA_LOCAL := $(LOCAL_PATH)/com_googlecode_leptonica_android
LEPTONICA_PATH := $(LEPTONICA_LOCAL)/src
include $(CLEAR_VARS)
LOCAL_MODULE := liblept
LOCAL_SRC_FILES := ../libs/$(TARGET_ARCH_ABI)/liblept.so
LOCAL_EXPORT_C_INCLUDES := \
$(LEPTONICA_LOCAL) \
$(LEPTONICA_PATH)/src
include $(PREBUILT_SHARED_LIBRARY)
#tesseract
TESSERACT_LOCAL := $(LOCAL_PATH)/com_googlecode_tesseract_android
TESSERACT_PATH := $(TESSERACT_LOCAL)/src
include $(CLEAR_VARS)
LOCAL_MODULE := libtess
LOCAL_SRC_FILES := ../libs/$(TARGET_ARCH_ABI)/libtess.so
LOCAL_EXPORT_C_INCLUDES := \
$(LOCAL_PATH) \
$(TESSERACT_PATH)/api \
$(TESSERACT_PATH)/ccmain \
$(TESSERACT_PATH)/ccstruct \
$(TESSERACT_PATH)/ccutil \
$(TESSERACT_PATH)/classify \
$(TESSERACT_PATH)/cube \
$(TESSERACT_PATH)/cutil \
$(TESSERACT_PATH)/dict \
$(TESSERACT_PATH)/opencl \
$(TESSERACT_PATH)/neural_networks/runtime \
$(TESSERACT_PATH)/textord \
$(TESSERACT_PATH)/viewer \
$(TESSERACT_PATH)/wordrec \
$(LEPTONICA_PATH)/src \
$(TESSERACT_LOCAL)
LOCAL_SHARED_LIBRARIES := liblept
include $(PREBUILT_SHARED_LIBRARY)
#opencv
include $(CLEAR_VARS)
OPENCV_PACKAGE_DIR:= /Users/danielsierraf/Documents/OpenCV-2.4.10-android-sdk/sdk
OPENCV_CAMERA_MODULES := off
include $(OPENCV_PACKAGE_DIR)/native/jni/OpenCV.mk
LOCAL_MODULE := run_detection
LOCAL_SRC_FILES := text_detect.cpp android.cpp
LOCAL_LDLIBS += -landroid -llog -ldl
LOCAL_SHARED_LIBRARIES += libtess liblept
include $(BUILD_SHARED_LIBRARY)

Your latest setup is failing in a weird way, ndk-build should at least try to compile your module. Maybe there is a bug in all-subdir-makefiles when there are ndk modules defined before it, and it doesn't find your module's Android.mk. You can try having only include $(call all-subdir-makefiles) inside your top level Android.mk.
Anyway, I think you should go back to your first setup, with your module directly in the jni root folder. Then, your main issue is the proper declaration of includes paths. tess-two/jni doesn't contain any headers ? They're in tess-two/jni/com_googlecode_*_android/src/*. That means you need to list these in your module declarations, by giving all the absolute paths to LOCAL_EXPORT_C_INCLUDES variables (like from the original Makefiles: https://github.com/rmtheis/tess-two/blob/master/tess-two/jni/com_googlecode_tesseract_android/Android.mk#L33)
You also need to add the dependency on liblept for libtess: LOCAL_SHARED_LIBRARIES := liblept inside libtess library declaration.
If it still fails, there is also another possibility: instead of redefining libtess and liblept modules using the generated .so files, you can directly include tess-two/jni/Android.mk and use the same Application.mk than tess-two (copy `tess-two/jni/Application.mk). It will already properly define libtess and liblept modules.

Android OpenCV - "error: cannot find -lopencv_java"

I'm trying to develope a native code with OpenCV using IntelliJ IDEA 13.1.4. When I try to ndk-build the code provided in mixedprocessing sample, I have this error:
[armeabi-v7a] Compile++ thumb: com_sample_jniLib <= com_sample_jniLib.cpp
[armeabi-v7a] SharedLibrary : libcom_sample_jniLib.so
D:/Workspace/android-ndk-r10/toolchains/arm-linux-androideabi-4.6/prebuilt/windows-x86_64/bin/../lib/gcc/arm-linux-androideabi/4.6/../../../../arm-linux-androideabi/bin/ld.exe: error: cannot find -lopencv_java
make.exe: *** [obj/local/armeabi-v7a/libcom_voxar_tracker_TrackerLib.so] Error 1
D:\Workspace\android-ndk-r10\sources\cxx-stl\stlport\stlport
Basically, he can't find -lopencv_java.
Here is my Android.mk:
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
include jni/opencv/OpenCV.mk
LOCAL_SRC_FILES := com_voxar_tracker_TrackerLib.cpp
LOCAL_MODULE := com_voxar_tracker_TrackerLib
LOCAL_LDLIBS += -llog -ldl
include $(BUILD_SHARED_LIBRARY)
And my Application.mk:
APP_STL := stlport_static
APP_CPPFLAGS := -frtti -fexceptions
APP_ABI := all
As I told before, I'm using IntelliJ IDEA 13.1.4, OpenCV 2.4.9 and Android NDK r10 32-bit on Windows 8.1. Does anybody have any idea of what that could be?

You seem to have forgot OPENCV_INSTALL_MODULES:=on in your Android.mk:
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
OPENCV_INSTALL_MODULES:=on
include jni/opencv/OpenCV.mk
LOCAL_SRC_FILES := com_voxar_tracker_TrackerLib.cpp
LOCAL_MODULE := com_voxar_tracker_TrackerLib
LOCAL_LDLIBS += -llog -ldl
include $(BUILD_SHARED_LIBRARY)

Android | fatal error: GLES/gl.h: No such file or directory

Android.mk
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_MODULE := test
LOCAL_CFLAGS := -Wall
LOCAL_SRC_FILES := test.c
LOCAL_LDLIBS := -llog -landroid -lEGL -lGLESv1_CM
include $(BUILD_SHARED_LIBRARY)
I run....
ndk-build NDK_PROJECT_PATH=./ APP_BUILD_SCRIPT=./Android.mk
and I get....
Compile thumb : test <= test.c
./test.c:8:29: fatal error: GLES/gl.h: No such file or directory
compilation terminated.
make: * [obj/local/armeabi/objs/test/test.o] Error 1
Now I am guessing adding a cflag of -I/include or a C_Include in the Android.mk will work but shouldn't that be handled by the -lGLESv1_CM.

Making an Application.mk file worked for me....
APP_ABI := armeabi armeabi-v7a
APP_PLATFORM := android-8

Android NDK: Including boost c++ library

I am trying to use a boost library inside my android application, using the NDK. I have found a couple of success stories here and here, but I can't say the same about me. I am specifically trying to use the library in this link, as well as the boost thread library. In the code below, I am only trying to include the thread library, not the math library. The process I used to build the boost libraries is pretty much the same as the first link I attached.
So far, it seems I have successfully built the boost libraries, but when I run ndk-build, I get the following error:
Prebuilt : libboost_thread.a <= <NDK>/sources/
cp: omitting directory `path/to/ndk/sources/boost'
make: *** [obj/local/armeabi/libboost_thread.a] Error 1
Obviously the cp: omitting directory... is not exactly an error. But the only thing I'm getting other than that is the next line, which doesn't really mean anything. Error 1
Here's my Android.mk file:
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_STATIC_LIBRARIES := boost_thread
LOCAL_LDLIBS := lboost_system-gcc-md lboost_thread-gcc-md -lgnustl_static
LOCAL_LDLIBS += lboost_system-gcc-md lboost_thread-gcc-md \
-L$(NDK_ROOT)/sources/cxx-stl/gnu-libstdc++/libs/armeabi \
-lgnustl_static
LOCAL_SRC_FILES := #cpp_sources
LOCAL_MODULE := com_example_ndkFile_CppMethods
include $(BUILD_SHARED_LIBRARY)
$(call import-module,boost)
And there's also an Android.mk file in path/to/ndk/sources/boost/:
LOCAL_PATH:= $(call my-dir)
include $(CLEAR_VARS)
LOCAL_MODULE:= boost_thread
LOCAL_SRC_FILES:= android/lib/libboost_thread.a
LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)
include $(PREBUILT_STATIC_LIBRARY)
And my humble Application.mk file:
APP_ABI := armeabi armeabi-v7a
APP_STL := gnustl_static
APP_CPPFLAGS = -fexceptions
I built the boost libraries using bjam. All of the libboost_###.a files are in the sources/boost/android/lib folder.
What is the error I'm getting?

I built the boost libraries using Boost-for-Android. Then I have in my boost/include/lib directory the android makefile boost.mk
LOCAL_PATH := $(call my-dir)
# boost_date_time
#
include $(CLEAR_VARS)
LOCAL_MODULE := boost_date_time
LOCAL_SRC_FILES := libboost_date_time-gcc-mt-1_53.a
include $(PREBUILT_STATIC_LIBRARY)
# boost_filesystem
#
include $(CLEAR_VARS)
LOCAL_MODULE := boost_filesystem
LOCAL_SRC_FILES := libboost_filesystem-gcc-mt-1_53.a
include $(PREBUILT_STATIC_LIBRARY)
# boost_thread
#
include $(CLEAR_VARS)
LOCAL_MODULE := boost_thread
LOCAL_SRC_FILES := libboost_thread-gcc-mt-1_53.a
include $(PREBUILT_STATIC_LIBRARY)
# boost_system
#
include $(CLEAR_VARS)
LOCAL_MODULE := boost_system
LOCAL_SRC_FILES := libboost_system-gcc-mt-1_53.a
include $(PREBUILT_STATIC_LIBRARY)
# boost_program_options
#
include $(CLEAR_VARS)
LOCAL_MODULE := boost_program_options
LOCAL_SRC_FILES := libboost_program_options-gcc-mt-1_53.a
include $(PREBUILT_STATIC_LIBRARY)
# boost_chrono
#
include $(CLEAR_VARS)
LOCAL_MODULE := boost_chrono
LOCAL_SRC_FILES := libboost_chrono-gcc-mt-1_53.a
include $(PREBUILT_STATIC_LIBRARY)
and my module where i use some of the boost libraries looks like this
LOCAL_PATH := $(call my-dir)
# SignalServer, executable
#
include $(CLEAR_VARS)
LOCAL_CFLAGS := -DTIXML_USE_TICPP
#LOCAL_CFLAGS += -DDEBUG
LOCAL_STATIC_LIBRARIES := boost_thread \
boost_system \
boost_filesystem \
boost_program_options \
boost_chrono \
LOCAL_STATIC_LIBRARIES += ticpp \
tia \
tobicore \
tobiid \
tid \
gdf
LOCAL_MODULE := signalserver
LOCAL_C_INCLUDES := $(LOCAL_PATH)/include
LOCAL_C_INCLUDES += $(LOCAL_PATH)/extern/include
LOCAL_C_INCLUDES += $(LOCAL_PATH)/../boost/include/boost-1_53
LOCAL_SRC_FILES := #cpp source
include $(BUILD_EXECUTABLE)
in addition I have an Android.mk where all subdir makefiles are listed
TOP_PATH := $(call my-dir)
include $(TOP_PATH)/boost/lib/boost.mk
include $(TOP_PATH)/signalserver/signalserver.mk
.
.
and my Application.mk:
APP_PLATFORM := android-14
APP_ABI := armeabi-v7a
#APP_OPTIM := debug
#NDK_DEBUG := 1
NDK_TOOLCHAIN_VERSION := 4.6
APP_STL := gnustl_static
APP_CPPFLAGS := -fexceptions -frtti

Here: http://silverglint.com/boost-for-android/ you can find a simple script that lets you build a modern version of boost for android, or simply download prebuilt boost binaries.
Also included is a sample test app that shows you how to include/link the boost headers/binaries