Cross compiling - opencv2/highgui.hpp: No such file or directory

[manolisan]

Hi,

I am trying to cross compile the library for an ARM machine with my host machine Ubuntu 16.04. However the make command results in the following error.

arm-linux-gnueabi-g++ -MD -MP -MT "./Bin/Intermediate/Arm-Release/BodySkeletonTracker/Skeleton.d Bin/Intermediate/Arm-Release/BodySkeletonTracker/Skeleton.o" -c -march=armv7-a -mtune=cortex-a9 -mfpu=neon -mfloat-abi=hard  -O3 -fno-tree-pre -fno-strict-aliasing -ftree-vectorize -ffast-math -funsafe-math-optimizations  -flax-vector-conversions -DUNIX -DGLX_GLXEXT_LEGACY -DDEPTH --sysroot=Staging -O2 -DNDEBUG -Iinclude -I/home/manolis/OpenNI-Linux-x64-2.3/Include -DXN_NEON -fPIC -fvisibility=hidden -Werror -o Bin/Intermediate/Arm-Release/BodySkeletonTracker/Skeleton.o src/Skeleton.cpp
In file included from src/Skeleton.cpp:1:0:
include/Skeleton.h:4:31: fatal error: opencv2/highgui.hpp: No such file or directory
compilation terminated.
CommonCppMakefile:133: recipe for target 'Bin/Intermediate/Arm-Release/BodySkeletonTracker/Skeleton.o' failed
make: *** [Bin/Intermediate/Arm-Release/BodySkeletonTracker/Skeleton.o] Error 1

Note that I have successfully compiled and run natively the code for my host x86 machine. So what am I missing?

Thanks a lot

[derzu]

Hi @manolisan,

The compiler is not finding the opencv2 include files. Is opencv installed on your device?

Please run this command on your terminal: pkg-config --cflags --libs opencv

Here on my machine the command exit is: -I/usr/local/include/opencv -I/usr/local/include -L/usr/local/lib -lopencv_shape -lopencv_stitching -lopencv_objdetect -lopencv_superres -lopencv_videostab -lopencv_calib3d -lopencv_features2d -lopencv_highgui -lopencv_videoio -lopencv_imgcodecs -lopencv_video -lopencv_photo -lopencv_ml -lopencv_imgproc -lopencv_flann -lopencv_viz -lopencv_core

This command is used at the Makefile, and it has the flags for include the opencv head files (-I/usr/local/include/opencv -I/usr/local/include).

If, in your device, it does not returns, you should replace the Makefile line #31: LDFLAGS += $(shell pkg-config --libs --static opencv) by: LDFLAGS += -I/usr/local/include/opencv -I/usr/local/include -L/usr/local/lib -lopencv_shape -lopencv_stitching -lopencv_objdetect -lopencv_superres -lopencv_videostab -lopencv_calib3d -lopencv_features2d -lopencv_highgui -lopencv_videoio -lopencv_imgcodecs -lopencv_video -lopencv_photo -lopencv_ml -lopencv_imgproc -lopencv_flann -lopencv_viz -lopencv_core

And install the opencv lib at your device.

[manolisan]

Thanks for the quick reply @derzu!

The output of the command pkg-config --cflags --libs opencv is

-I/usr/local/include/opencv -I/usr/local/include -L/usr/local/lib -lopencv_stitching -lopencv_superres -lopencv_videostab -lopencv_aruco -lopencv_bgsegm -lopencv_bioinspired -lopencv_ccalib -lopencv_dnn -lopencv_dpm -lopencv_fuzzy -lopencv_line_descriptor -lopencv_optflow -lopencv_plot -lopencv_reg -lopencv_saliency -lopencv_stereo -lopencv_structured_light -lopencv_rgbd -lopencv_surface_matching -lopencv_tracking -lopencv_datasets -lopencv_text -lopencv_face -lopencv_xfeatures2d -lopencv_shape -lopencv_video -lopencv_ximgproc -lopencv_calib3d -lopencv_features2d -lopencv_flann -lopencv_xobjdetect -lopencv_objdetect -lopencv_ml -lopencv_xphoto -lopencv_highgui -lopencv_videoio -lopencv_imgcodecs -lopencv_photo -lopencv_imgproc -lopencv_core

I did the suggested replacement in the Makefile line #31 and I got the same error.

Opencv lib is installed on my device and I have successfully compiled and run your code on my host device, but I haven't compiled it for an arm device.

So, maybe the problem could be that I haven't cross-compiled opencv.

[derzu]

I think I found the problem.

Replace the line include/Skeleton.h:4 #include <opencv2/highgui.hpp> for #include <opencv2/highgui/highgui.hpp>

You will probably get more errors, please change also this include, on the files where it happens: #include <opencv2/core.hpp> to #include <opencv2/core/core.hpp>

Please let me know if it works.

Check this answer at StackOverflow: https://stackoverflow.com/a/43701862/1178478

[manolisan]

No, that didn't work.

I added this line: INC_DIRS += /usr/local/include in the Makefile:40. Now I can get the source files compiled to intermediate object files, but I get an error while loading the libraries in the linking phase.

arm-linux-gnueabi-g++ -o Bin/Arm-Release/BodySkeletonTracker ./Bin/Intermediate/Arm-Release/BodySkeletonTracker/Skeleton.o ./Bin/Intermediate/Arm-Release/BodySkeletonTracker/Point3D.o ./Bin/Intermediate/Arm-Release/BodySkeletonTracker/SkeletonPoints.o ./Bin/Intermediate/Arm-Release/BodySkeletonTracker/DrawAux.o ./Bin/Intermediate/Arm-Release/BodySkeletonTracker/SkeletonListener.o ./Bin/Intermediate/Arm-Release/BodySkeletonTracker/SkeletonDepth.o ./Bin/Intermediate/Arm-Release/BodySkeletonTracker/SampleViewer.o ./Bin/Intermediate/Arm-Release/BodySkeletonTracker/main.o -L/usr/local/lib -lopencv_stitching -lopencv_superres -lopencv_videostab -lopencv_aruco -lopencv_bgsegm -lopencv_bioinspired -lopencv_ccalib -lopencv_dnn -lopencv_dpm -lopencv_fuzzy -lopencv_line_descriptor -lopencv_optflow -lopencv_plot -lopencv_reg -lopencv_saliency -lopencv_stereo -lopencv_structured_light -lopencv_rgbd -lopencv_surface_matching -lopencv_tracking -lopencv_datasets -lopencv_text -lopencv_face -lopencv_xfeatures2d -lopencv_shape -lopencv_video -lopencv_ximgproc -lopencv_calib3d -lopencv_features2d -lopencv_flann -lopencv_xobjdetect -lopencv_objdetect -lopencv_ml -lopencv_xphoto -lopencv_highgui -lopencv_videoio -lopencv_imgcodecs -lopencv_photo -lopencv_imgproc -lopencv_core -lpng -lz -ltiff -ljasper -ljpeg -lgtk-3 -lgdk-3 -lpangocairo-1.0 -lpango-1.0 -latk-1.0 -lcairo-gobject -lcairo -lgdk_pixbuf-2.0 -lgio-2.0 -lgobject-2.0 -lgthread-2.0 -lglib-2.0 -lv4l1 -lv4l2 -lavcodec-ffmpeg -lavformat-ffmpeg -lavutil-ffmpeg -lswscale-ffmpeg -ldl -lm -lpthread -lrt --sysroot=Staging  -LBin/Arm-Release -lOpenNI2 -Wl,-rpath ./
/usr/local/lib/libopencv_stitching.so: file not recognized: File format not recognized
collect2: error: ld returned 1 exit status
CommonCppMakefile:139: recipe for target 'Bin/Arm-Release/BodySkeletonTracker' failed
make: *** [Bin/Arm-Release/BodySkeletonTracker] Error 1