I am trying to compile OpenCV in native on Android Studio. I am trying to follow : https://sriraghu.com/2017/03/11/opencv-in-android-an-introduction-part-1/
I was succesfully able to do it by following these steps on Windows. However on Ubuntu, its not working. The error is :
Execution failed for task ‘:app:externalNativeBuildDebug’.
Build command failed. Error while executing process /home/user/Android/Sdk/cmake/3.6.4111459/bin/cmake with arguments {–build
/home/user/AndroidStudioProjects/project_folders/app/.externalNativeBuild/cmake/debug/arm64-v8a
–target native-lib}
ninja: error: ‘../../../../jniLibs/src/main/jniLibs/arm64-v8a/libopencv_java3.so’,
needed by
‘../../../../build/intermediates/cmake/debug/obj/arm64-v8a/libnative-lib.so’,
missing and no known rule to make it
The CMakeLists.txt file is:
cmake_minimum_required(VERSION 3.4.1)
set(pathToOpenCV /media/user/Stuff/Softwares/OpenCV-android-sdk/sdk/native)
include_directories(${pathToOpenCV}/jni/include)
add_library( # Sets the name of the library.
native-lib
# Sets the library as a shared library.
SHARED
# Provides a relative path to your source file(s).
src/main/cpp/native-lib.cpp )
# Searches for a specified prebuilt library and stores the path as a
# variable. Because CMake includes system libraries in the search path by
# default, you only need to specify the name of the public NDK library
# you want to add. CMake verifies that the library exists before
# completing its build.
add_library(lib_opencv SHARED IMPORTED)
set_target_properties(lib_opencv PROPERTIES IMPORTED_LOCATIONS /home/user/cmu/android-apps/OpenCV_app_June23/OpenCV_Android/app/src/main/jniLibs/arm64-v8a/libopencv_java3.so)
find_library( # Sets the name of the path variable.
log-lib
# Specifies the name of the NDK library that
# you want CMake to locate.
log )
# Specifies libraries CMake should link to your target library. You
# can link multiple libraries, such as libraries you define in this
# build script, prebuilt third-party libraries, or system libraries.
target_link_libraries( # Specifies the target library.
native-lib
# Links the target library to the log library
# included in the NDK.
${log-lib} lib_opencv)
In native-lib.cpp, I am able to add #include without any error prompts in Android Studio.
My previous searches suggest that there is something wrong with the paths. I have checked that the paths are correct, or is there a different way to put the path in Ubuntu?
Related
Got error when I build the project like in the below. I tried so many things but never succeeded. I'm using m1 MacBook. Is this related with this error ?
[CXX1405] exception while building Json A problem occurred starting process 'command '/Users/serhat/Library/Android/sdk/cmake/3.18.1/bin/cmake''
in build.gradle:
externalNativeBuild {
cmake {
path "CMakeLists.txt"
}
}
and this is CmakeList.txt :
# For more information about using CMake with Android Studio,read the
# documentation: https://d.android.com/studio/projects/add-native-code.html
# Sets the minimum version of CMake required to build the native library.
cmake_minimum_required(VERSION 3.4.1)
# Creates and names a library, sets it as either STATIC
# or SHARED, and provides the relative paths to its source code.
# You can define multiple libraries, and CMake builds them for you.
# Gradle automatically packages shared libraries with your APK.
add_library( # Sets the name of the library.
native-lib
# Sets the library as a shared library.
SHARED
# Provides a relative path to your source file(s).
src/main/cpp/native-lib.cpp )
# Searches for a specified prebuilt library and stores the path as a
# variable. Because CMake includes system libraries in the search path by
# default, you only need to specify the name of the public NDK library
# you want to add. CMake verifies that the library exists before
# completing its build.
find_library( # Sets the name of the path variable.
log-lib
# Specifies the name of the NDK library that
# you want CMake to locate.
log )
# Specifies libraries CMake should link to your target library. You
# can link multiple libraries, such as libraries you define in this
# build script, prebuilt third-party libraries, or system libraries.
target_link_libraries( # Specifies the target library.
native-lib
# Links the target library to the log library
# included in the NDK.
${log-lib} )
I fixed this issue :
softwareupdate --install-rosetta
I am getting the following CMake error:
CMake Error at CMakeLists.txt:23 (find_package):
By not providing "FindQt5.cmake" in CMAKE_MODULE_PATH this project has
asked CMake to find a package configuration file provided by "Qt5", but
CMake did not find one.
Could not find a package configuration file provided by "Qt5" with any of
the following names:
Qt5Config.cmake
qt5-config.cmake
Add the installation prefix of "Qt5" to CMAKE_PREFIX_PATH or set "Qt5_DIR"
to a directory containing one of the above files. If "Qt5" provides a
separate development package or SDK, be sure it has been installed.
In my CMakeLists.txt, there is this line:
if (NOT CMAKE_PREFIX_PATH)
message(WARNING "CMAKE_PREFIX_PATH is not defined, you may need to set it "
"(-DCMAKE_PREFIX_PATH=\"path/to/Qt/lib/cmake\" or -DCMAKE_PREFIX_PATH=/usr/include/{host}/qt{version}/ on Ubuntu)")
endif ()
So I did what it says and set my PREFIX_PATH to "/usr/include/x86_64-linux-gnu/qt5/".
However, the error I get says that CMake cannot find "qt5-config.cmake", which is located at "/usr/lib/x86_64-linux-gnu/cmake/Qt5" and not "/usr/include/x86_64-linux-gnu/qt5/", so I tried setting the "Qt5_DIR" to that directory (since it says in the error to set it to a dir that contains the above files) but still without success. Any ideas why it cant find the files it needs?
edit:
my CMakeLists.txt:
cmake_minimum_required(VERSION 3.19)
project(untitled1)
set(CMAKE_CXX_STANDARD 14)
set(CMAKE_PREFIX_PATH "/usr/lib/x86_64-linux-gnu/cmake/Qt5/")
set(CMAKE_AUTOMOC ON)
set(CMAKE_AUTORCC ON)
set(CMAKE_AUTOUIC ON)
set(QT_VERSION 5)
set(REQUIRED_LIBS Core Gui Widgets)
set(REQUIRED_LIBS_QUALIFIED Qt5::Core Qt5::Gui Qt5::Widgets)
add_executable(${PROJECT_NAME} main.cpp)
if (NOT CMAKE_PREFIX_PATH)
message(WARNING "CMAKE_PREFIX_PATH is not defined, you may need to set it "
"(-DCMAKE_PREFIX_PATH=\"path/to/Qt/lib/cmake\" or -DCMAKE_PREFIX_PATH=/usr/include/{host}/qt{version}/ on Ubuntu)")
endif ()
find_package(Qt${QT_VERSION} COMPONENTS ${REQUIRED_LIBS} REQUIRED)
target_link_libraries(${PROJECT_NAME} ${REQUIRED_LIBS_QUALIFIED})
note that the file has been auto-generated by CLion, all I did was change the path according to what is specified in the if-Block
I'm trying to learn a bit of Android development.
I've started a new project for a simple hello world and it works fine.
The project is essentially the default one + one more header file in the cpp folder,
However I can't see such .cpp in the project mode, can anyone suggest how to fix this?
(See picture below).
I've attempted to change some setting in File > Project Structure but it doesn't seem to make any difference.
Maybe worth noticing that the header file isn't listed in the CMakeLists.txt at all.
# For more information about using CMake with Android Studio, read the
# documentation: https://d.android.com/studio/projects/add-native-code.html
# Sets the minimum version of CMake required to build the native library.
cmake_minimum_required(VERSION 3.4.1)
# Creates and names a library, sets it as either STATIC
# or SHARED, and provides the relative paths to its source code.
# You can define multiple libraries, and CMake builds them for you.
# Gradle automatically packages shared libraries with your APK.
add_library( # Sets the name of the library.
native-lib
# Sets the library as a shared library.
SHARED
# Provides a relative path to your source file(s).
src/main/cpp/native-lib.cpp )
# Searches for a specified prebuilt library and stores the path as a
# variable. Because CMake includes system libraries in the search path by
# default, you only need to specify the name of the public NDK library
# you want to add. CMake verifies that the library exists before
# completing its build.
find_library( # Sets the name of the path variable.
log-lib
# Specifies the name of the NDK library that
# you want CMake to locate.
log )
# Specifies libraries CMake should link to your target library. You
# can link multiple libraries, such as libraries you define in this
# build script, prebuilt third-party libraries, or system libraries.
target_link_libraries( # Specifies the target library.
native-lib
# Links the target library to the log library
# included in the NDK.
${log-lib} )
According to the android doc:
Known Issue: Android Studio currently shows you only the header files that have matching source files—even if you specify other headers in your CMake build script. See Issue #38068472
This means you need a pair filename.h and filename.cpp, you modify your CMakeLists.txt accordingly. The header file will be shown in project mode if it has a corresponding .cpp with the same name.
Reference:
https://developer.android.com/studio/projects/add-native-code
I'm new to CMake. I copied a small vtk example from the link http://www.vtk.org/Wiki/VTK/Examples/Cxx/IO/SimplePointsReader and used CMake to compile. And it gives me an error, " Error in configuration process, Project files may be invalid".
It shows me the errors,
CMake Error at CMakeLists.txt:5 (find_package): By not providing
"FindVTK.cmake" in CMAKE_MODULE_PATH this project has asked CMake to
find a package configuration file provided by "VTK", but CMake did
not find one.
Could not find a package configuration file provided by "VTK" with
any of the following names:
VTKConfig.cmake
vtk-config.cmake
Add the installation prefix of "VTK" to CMAKE_PREFIX_PATH or set
"VTK_DIR" to a directory containing one of the above files. If
"VTK" provides a separate development package or SDK, be sure it has
been installed.
I have already installed vtk in my pc and please help me with this problem.
CMakeLists.txt contains the following code
cmake_minimum_required(VERSION 2.8)
PROJECT(SimplePointsReader)
find_package(VTK REQUIRED)
include(${VTK_USE_FILE})
add_executable(SimplePointsReader MACOSX_BUNDLE SimplePointsReader)
if(VTK_LIBRARIES)
target_link_libraries(SimplePointsReader ${VTK_LIBRARIES})
else()
target_link_libraries(SimplePointsReader vtkHybrid vtkWidgets)
endif()
I've solved this problem by setting VTK_DIR=path_to_VTK/bin as an environment variable, because CMakeList.txt file's changing was not helpful.
I am creating an object tracking program which rely on OpenCV. Thus I want to be able to test it with different versions of OpenCV but I have linking errors.
I installed the last version of OpenCV (a69b435c928f422fb5f99c02cf2dcae57dcf820a) in the following folder : /usr/local/opencv/opencv-trunk instead of the usual /usr/local.
Then I followed also the official tutorial to use OpenCV with CMake in Linux, but I had the following "normal" error :
CMake Error at CMakeLists.txt:11 (find_package):
By not providing "FindOpenCV.cmake" in CMAKE_MODULE_PATH this project has asked CMake to find a package configuration file provided by "OpenCV", but CMake did not find one.
Could not find a package configuration file provided by "OpenCV" with any of the following names:
OpenCVConfig.cmake
opencv-config.cmake
Add the installation prefix of "OpenCV" to CMAKE_PREFIX_PATH or set "OpenCV_DIR" to a directory containing one of the above files. If "OpenCV" provides a separate development package or SDK, be sure it has been installed.
-- Configuring incomplete, errors occurred!
So I did what was suggested and added the following line in my CMakeLists.txt :
# Find independently installed OpenCV libraries
set(OpenCV_DIR "/usr/local/opencv/opencv-trunk/share/OpenCV")
This is the complete CMakeLists.txt file :
# Find independently installed OpenCV libraries
set(OpenCV_DIR "/usr/local/opencv/opencv-trunk/share/OpenCV")
cmake_minimum_required(VERSION 2.8)
project( DisplayImage )
add_executable( DisplayImage DisplayImage.cpp )
find_package( OpenCV REQUIRED )
include_directories( ${OpenCV_INCLUDE_DIRS} )
target_link_libraries( DisplayImage ${OpenCV_LIBS} )
Now I have the following error and I don't find how to deal with it.
CMake Error at CMakeLists.txt:12 (find_package):
Found package configuration file:
/usr/local/opencv/opencv-trunk/share/OpenCV/OpenCVConfig.cmake
but it set OpenCV_FOUND to FALSE so package "OpenCV" is considered to be NOT FOUND.
-- Configuring incomplete, errors occurred!
If you have already faced that issue in such context your solutions are welcomed ;)
If you are running IntelliJ or any other IDE, just try re-building CMake cache (or just remove your build directory and run cmake utility again).
I believe this is not the best practice - to set the configuration variable like OpenCV_DIR hard-coded in the CMakeLists.txt. Try setting it manually, as an environment variable to the cmake utility:
OpenCV_DIR=/usr/local/Cellar/opencv3/3.1.0_2/share/OpenCV/ cmake ..
or set your IDE to make this for you: