Hello, I recently started using opencv for Android in a project, however I need to reduce apk size, and so i found install-opencv-on-android-tiny-and-optimized
Apparently is possible to generate the opencv.so files with fewer modules, like core and imgproc in the example above, which is just what I need, but i don't know how to do all that since I'm in Windows 10.
Can I use the the opencv 4.1.2 (Which is the version I'm using in my project)?
Can I use the latest Android NDK?
Can I compile against the latest Android API (29 currently) ?
If someone could point me in the right direction it would be really great.
UPDATE 25/10/19:
Following mvuori's suggestion I tried to apply many different examples for building OpenCV in Windows, and I've managed to generate core and imgproc .so; However as I need to build libopencv_java.so for each valid Android architecture I made some changes to what I was doing, but now it always fail at 99%
This is the error i get:
C:\MinGW\bin\strip.exe: Unable to recognise the format of the input file `C:/Users/mauro/Downloads/opencv-4.1.2/build/jni/armeabi-v7a/libopencv_java4.so'
modules\java\jni\CMakeFiles\opencv_java.dir\build.make:174: recipe for target 'jni/armeabi-v7a/libopencv_java4.so' failed
mingw32-make[2]: * [jni/armeabi-v7a/libopencv_java4.so] Error 1
mingw32-make[2]: Deleting file 'jni/armeabi-v7a/libopencv_java4.so'
CMakeFiles\Makefile2:1536: recipe for target 'modules/java/jni/CMakeFiles/opencv_java.dir/all' failed
mingw32-make[1]: [modules/java/jni/CMakeFiles/opencv_java.dir/all] Error 2
Makefile:161: recipe for target 'all' failed
mingw32-make: * [all] Error 2
This is my CMake configuration:
General configuration for OpenCV 4.1.2 =====================================
Version control: unknown
Platform:
Timestamp: 2019-10-25T23:25:56Z
Host: Windows 10.0.18362 AMD64
Target: Android 1 armv7-a
CMake: 3.16.0-rc2
CMake generator: MinGW Makefiles
CMake build tool: C:/MinGW/bin/mingw32-make.exe
Configuration: Release
CPU/HW features:
Baseline:
requested: DETECT
C/C++:
Built as dynamic libs?: YES
C++ Compiler: C:/Users/mauro/AppData/Local/Android/Sdk/ndk/20.0.5594570/toolchains/llvm/prebuilt/windows-x86_64/bin/clang++.exe (ver 8.0)
C++ flags (Release): -g -DANDROID -fdata-sections -ffunction-sections -funwind-tables -fstack-protector-strong -no-canonical-prefixes -fno-addrsig -march=armv7-a -mthumb -Wa,--noexecstack -Wformat -Werror=format-security -fsigned-char -W -Wall -Werror=return-type -Werror=non-virtual-dtor -Werror=address -Werror=sequence-point -Wformat -Werror=format-security -Wmissing-declarations -Wmissing-prototypes -Wstrict-prototypes -Wundef -Winit-self -Wpointer-arith -Wshadow -Wsign-promo -Wuninitialized -Winit-self -Winconsistent-missing-override -Wno-delete-non-virtual-dtor -Wno-unnamed-type-template-args -Wno-comment -fdiagnostics-show-option -ffunction-sections -fdata-sections -fvisibility=hidden -fvisibility-inlines-hidden -Oz -DNDEBUG -DNDEBUG
C++ flags (Debug): -g -DANDROID -fdata-sections -ffunction-sections -funwind-tables -fstack-protector-strong -no-canonical-prefixes -fno-addrsig -march=armv7-a -mthumb -Wa,--noexecstack -Wformat -Werror=format-security -fsigned-char -W -Wall -Werror=return-type -Werror=non-virtual-dtor -Werror=address -Werror=sequence-point -Wformat -Werror=format-security -Wmissing-declarations -Wmissing-prototypes -Wstrict-prototypes -Wundef -Winit-self -Wpointer-arith -Wshadow -Wsign-promo -Wuninitialized -Winit-self -Winconsistent-missing-override -Wno-delete-non-virtual-dtor -Wno-unnamed-type-template-args -Wno-comment -fdiagnostics-show-option -ffunction-sections -fdata-sections -fvisibility=hidden -fvisibility-inlines-hidden -O0 -fno-limit-debug-info -DDEBUG -D_DEBUG
C Compiler: C:/Users/mauro/AppData/Local/Android/Sdk/ndk/20.0.5594570/toolchains/llvm/prebuilt/windows-x86_64/bin/clang.exe
C flags (Release): -g -DANDROID -fdata-sections -ffunction-sections -funwind-tables -fstack-protector-strong -no-canonical-prefixes -fno-addrsig -march=armv7-a -mthumb -Wa,--noexecstack -Wformat -Werror=format-security -fsigned-char -W -Wall -Werror=return-type -Werror=non-virtual-dtor -Werror=address -Werror=sequence-point -Wformat -Werror=format-security -Wmissing-declarations -Wmissing-prototypes -Wstrict-prototypes -Wundef -Winit-self -Wpointer-arith -Wshadow -Wsign-promo -Wuninitialized -Winit-self -Winconsistent-missing-override -Wno-delete-non-virtual-dtor -Wno-unnamed-type-template-args -Wno-comment -fdiagnostics-show-option -Qunused-arguments -ffunction-sections -fdata-sections -fvisibility=hidden -fvisibility-inlines-hidden -Oz -DNDEBUG -DNDEBUG
C flags (Debug): -g -DANDROID -fdata-sections -ffunction-sections -funwind-tables -fstack-protector-strong -no-canonical-prefixes -fno-addrsig -march=armv7-a -mthumb -Wa,--noexecstack -Wformat -Werror=format-security -fsigned-char -W -Wall -Werror=return-type -Werror=non-virtual-dtor -Werror=address -Werror=sequence-point -Wformat -Werror=format-security -Wmissing-declarations -Wmissing-prototypes -Wstrict-prototypes -Wundef -Winit-self -Wpointer-arith -Wshadow -Wsign-promo -Wuninitialized -Winit-self -Winconsistent-missing-override -Wno-delete-non-virtual-dtor -Wno-unnamed-type-template-args -Wno-comment -fdiagnostics-show-option -Qunused-arguments -ffunction-sections -fdata-sections -fvisibility=hidden -fvisibility-inlines-hidden -O0 -fno-limit-debug-info -DDEBUG -D_DEBUG
Linker flags (Release): -Wl,--exclude-libs,libgcc.a -Wl,--exclude-libs,libatomic.a -static-libstdc++ -Wl,--build-id -Wl,--warn-shared-textrel -Wl,--fatal-warnings -Wl,--exclude-libs,libunwind.a -Wl,--no-undefined -Qunused-arguments -Wl,-z,noexecstack -Wl,--gc-sections
Linker flags (Debug): -Wl,--exclude-libs,libgcc.a -Wl,--exclude-libs,libatomic.a -static-libstdc++ -Wl,--build-id -Wl,--warn-shared-textrel -Wl,--fatal-warnings -Wl,--exclude-libs,libunwind.a -Wl,--no-undefined -Qunused-arguments -Wl,-z,noexecstack -Wl,--gc-sections
ccache: NO
Precompiled headers: NO
Extra dependencies: dl m log
3rdparty dependencies:
OpenCV modules:
To be built: core imgproc java
Disabled: world
Disabled by dependency: calib3d dnn features2d flann highgui imgcodecs ml objdetect photo stitching ts video videoio
Unavailable: gapi js python2 python3
Applications: -
Documentation: NO
Non-free algorithms: NO
Android NDK: C:/Users/mauro/AppData/Local/Android/Sdk/ndk/20.0.5594570 (ver 20.0.5594570)
Android ABI: armeabi-v7a
NDK toolchain: arm-linux-androideabi-clang
STL type: c++_static
Native API level: 17
Android SDK: not used, projects are not built
GUI:
Media I/O:
ZLib: C:/Users/mauro/AppData/Local/Android/Sdk/ndk/20.0.5594570/toolchains/llvm/prebuilt/windows-x86_64/sysroot/usr/lib/arm-linux-androideabi/libz.a (ver 1.2.7)
JPEG: build-libjpeg-turbo (ver 2.0.2-62)
WEBP: build (ver encoder: 0x020e)
PNG: build (ver 1.6.37)
TIFF: build (ver 42 - 4.0.10)
JPEG 2000: build (ver 1.900.1)
OpenEXR: build (ver 2.3.0)
HDR: YES
SUNRASTER: YES
PXM: YES
PFM: YES
Video I/O:
Parallel framework: pthreads
Trace: YES (built-in)
Other third-party libraries:
Custom HAL: YES (carotene (ver 0.0.1))
Protobuf: build (3.5.1)
Python (for build): C:/Users/mauro/AppData/Local/Programs/Python/Python38/python.exe
Java:
ant: C:/ant/bin/ant.bat (ver )
Java wrappers: YES
Java tests: NO
Install to: C:/Users/mauro/Downloads/opencv-4.1.2/build/install
