expanding the using-opencv example to include blob detection about acap-native-sdk-examples

[pataxis]

Hi @stephanschulz , thank you for reaching out to us with this suggestion. We will get back to you when we have had a look.

[stephanschulz]

i tried the following:

add #include <opencv2/features2d.hpp>

edit the Dockerfile to include -D BUILD_LIST=core,imgproc,video,features2d,objdetect \ in lline 76 https://github.com/AxisCommunications/acap-native-sdk-examples/blob/master/using-opencv/Dockerfile#L76

But still get errors

 > [12/12] RUN . /opt/axis/acapsdk/environment-setup* && acap-build .:
#16 0.333 make
#16 0.335 mkdir -p ./lib
#16 0.342 cp /target-root/usr/lib/libopencv_core.so.4.5 /target-root/usr/lib/libopencv_core.so.4.5.1 /target-root/usr/lib/libopencv_core.so ./lib
#16 0.350 cp /target-root/usr/lib/libopencv_imgproc.so.4.5.1 /target-root/usr/lib/libopencv_imgproc.so /target-root/usr/lib/libopencv_imgproc.so.4.5 ./lib
#16 0.359 cp /target-root/usr/lib/libopencv_video.so /target-root/usr/lib/libopencv_video.so.4.5 /target-root/usr/lib/libopencv_video.so.4.5.1 ./lib
#16 0.367 arm-linux-gnueabihf-g++  -mthumb -mfpu=neon -mfloat-abi=hard -mcpu=cortex-a9 -fstack-protector-strong  -O2 -D_FORTIFY_SOURCE=2 -Wformat -Wformat-security -Werror=format-security --sysroot=/opt/axis/acapsdk/sysroots/armv7hf -L/opt/axis/acapsdk/sysroots/armv7hf/usr/lib example.cpp  -O2 -pipe -g -feliminate-unused-debug-types  -Os -pipe -std=c++11 -I/opt/axis/acapsdk/sysroots/armv7hf/usr/include/vdo -I/opt/axis/acapsdk/sysroots/armv7hf/usr/include/gio-unix-2.0 -I/opt/axis/acapsdk/sysroots/armv7hf/usr/include/glib-2.0 -I/opt/axis/acapsdk/sysroots/armv7hf/usr/lib/glib-2.0/include -I/target-root/usr/include/opencv4 -L./lib -Wl,--no-as-needed,-rpath,'$ORIGIN/lib' -lm -lopencv_video -lopencv_imgproc -lopencv_core -lpthread -lvdostream -lsystemd -lgio-2.0 -lgobject-2.0 -lglib-2.0 imgprovider.cpp -o opencv_app && arm-linux-gnueabihf-strip --strip-unneeded opencv_app
#16 1.925 /usr/lib/gcc-cross/arm-linux-gnueabihf/9/../../../../arm-linux-gnueabihf/bin/ld: warning: libopencv_calib3d.so.4.5, needed by ./lib/libopencv_video.so, not found (try using -rpath or -rpath-link)
#16 1.925 /usr/lib/gcc-cross/arm-linux-gnueabihf/9/../../../../arm-linux-gnueabihf/bin/ld: /tmp/cclv1ky1.o: in function `main':
#16 1.925 /opt/app/example.cpp:101: undefined reference to `cv::SimpleBlobDetector::Params::Params()'
#16 1.925 /usr/lib/gcc-cross/arm-linux-gnueabihf/9/../../../../arm-linux-gnueabihf/bin/ld: /opt/app/example.cpp:136: undefined reference to `cv::SimpleBlobDetector::create(cv::SimpleBlobDetector::Params const&)'
#16 1.925 /usr/lib/gcc-cross/arm-linux-gnueabihf/9/../../../../arm-linux-gnueabihf/bin/ld: ./lib/libopencv_video.so: undefined reference to `cv::estimateAffine2D(cv::_InputArray const&, cv::_InputArray const&, cv::_OutputArray const&, int, double, unsigned int, double, unsigned int)'
#16 1.925 /usr/lib/gcc-cross/arm-linux-gnueabihf/9/../../../../arm-linux-gnueabihf/bin/ld: ./lib/libopencv_video.so: undefined reference to `cv::estimateAffinePartial2D(cv::_InputArray const&, cv::_InputArray const&, cv::_OutputArray const&, int, double, unsigned int, double, unsigned int)'
#16 1.925 collect2: error: ld returned 1 exit status
#16 1.926 make: *** [Makefile:30: opencv_app] Error 1
#16 1.927 
#16 1.927 make failed. Please fix above errors, before you can create a package
------
executor failed running [/bin/bash -o pipefail -c . /opt/axis/acapsdk/environment-setup* && acap-build .]: exit code: 1
stephanschulz@Komputer using-opencv % 

[Corallo]

Hello! To build Opencv with more libraries you can do the following:

First, add the libraries to the build in the docker file, line 76:
-D BUILD_LIST=core,imgproc,video,features2d,objdetect

then in the makefile Line 19, you add those shared libs (and their dependency)

SHLIBS += -lm -lopencv_calib3d -lopencv_features2d -lopencv_flann -lopencv_video -lopencv_imgproc -lopencv_core -lpthread

Then, you need to copy the .so files to the local lib directory, which means adding a new command in line 21 and line 34 to find and copy the right .so files.
To make this last step more simple, you could also copy all the opencv libs,

replacing line 21,22,23 with:
LIB_FILES = $(wildcard $(SDK_TARGET_LIBS)/libopencv_*.so*)
and
34,35,36 with:
cp $(LIB_FILES) $(SHLIB_DIR)

[pataxis]

No updates after answer, closing issue.