Transient dependencies are bundled into the APK but not linked in the jni wrapper

ffmpeg-jni-cmakelist.txt

#
# Copyright (C) The Android Open Source Project
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#      http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#

cmake_minimum_required(VERSION 3.4.1)
set(CMAKE_SYSROOT "/Users/gopinath/Library/Android/sdk/ndk-bundle/platforms/android-16/arch-arm")
set (CMAKE_SHARED_LINKER_FLAGS "-Wl,--as-needed,-v")
# configure import libs
set(distribution_DIR ${CMAKE_SOURCE_DIR}/../../../../sharedlibs)

add_library(lib_ffmpeg SHARED IMPORTED)
set_target_properties(lib_ffmpeg PROPERTIES IMPORTED_LOCATION
    ${distribution_DIR}/ffmpeg/lib/armeabi/libavcodec.so)


# build application's shared lib
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=gnu++11")

add_library(ffmpeg-jni SHARED
            tutorial02.c)

set(THREADS_PREFER_PTHREAD_FLAG ON)
find_package(Threads REQUIRED)
target_link_libraries(ffmpeg-jni Threads::Threads)

target_include_directories(ffmpeg-jni PRIVATE
                           ${distribution_DIR}/ffmpeg/include
                           )

target_link_libraries(ffmpeg-jni
                      android
                      -ljnigraphics
                      lib_ffmpeg
                      log)

Two problems with your gist:

• you should not override CMAKE_SHARED_LINKER_FLAGS for Android. If you badly need to, you can extend it:

  set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -Wl,--whatever-you-need")
  

• If you want to see verbose linker output, use -v without -Wl,:

  set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -Wl,--as-needed -v"")
  

If you keep the CMAKE_SHARED_LINKER_FLAGS that Android toolchain prepares for you, you get -Wl,--no-undefined which will complain when it doesn't find 'av_register_all', and it will set the path to platforms/android-16/arch-arm for you, so you don't need to set CMAKE_SYSROOT.

Thanks Alex for taking time and identifying the newbie problems.