Building / Cross Compiling OpenCV for Linux ARM /MIPS

1) simple mode

cd opencv-3.4.9

mkdir build

cmake ../

-DCMAKE_C_COMPILER=mips-linux-gnu-gcc

-DCMAKE_CXX_COMPILER=mips-linux-gnu-g++

-DOPENCV_FORCE_3RDPARTY_BUILD=ON

-DBUILD_ZLIB=ON

-DCMAKE_INSTALL_PREFIX=../output

2) crop mode

cd opencv-3.4.9

mkdir build

cmake ../

-DCMAKE_C_COMPILER=mips-linux-gnu-gcc

-DCMAKE_CXX_COMPILER=mips-linux-gnu-g++

-DOPENCV_FORCE_3RDPARTY_BUILD=ON

-DBUILD_ZLIB=ON -DWITH_GTK=OFF -DWITH_GTK=OFF

-DWITH_GTK_2_X=OFF -DWITH_CUDA=OFF -DWITH_IPP=OFF

-DWITH_OPENCL=OFF -DWITH_OPENCLAMDBLAS=OFF

-DWITH_QUIRC=OFF -DWITH_OPENCLAMDFFT=OFF

-DWITH_1394=OFF -DWITH_FFMPEG=OFF -DWITH_WEBP=OFF

-DWITH_TIFF=OFF -DWITH_OPENEXR=OFF -DWITH_PNG=OFF

-DWITH_PROTOBUF=OFF -DWITH_GSTREAMER=OFF -DWITH_IMGCODEC_SUNRASTER=OFF

-DBUILD_SHARED_LIBS=OFF -DBUILD_opencv_ts=OFF

-DBUILD_opencv_shape=OFF -DBUILD_opencv_stitching=OFF

-DBUILD_opencv_apps=OFF -DBUILD_opencv_calib3d=OFF

-DBUILD_opencv_dnn=OFF -DBUILD_opencv_features2d=OFF

-DBUILD_opencv_flann=OFF -DBUILD_opencv_highgui=OFF

-DBUILD_opencv_ml=OFF -DBUILD_opencv_objdetect=OFF

-DBUILD_opencv_photo=OFF -DBUILD_opencv_video=OFF

-DBUILD_opencv_videoio=OFF -DBUILD_opencv_videostab=OFF

-DCMAKE_BUILD_TYPE=RELEASE

-DCMAKE_INSTALL_PREFIX=../output

-DCMAKE_C_FLAGS=-m64 -DCMAKE_CXX_FLAGS=-m64

-DCMAKE_CXX_FLAGS="-s -Os" -DCMAKE_C_FLAGS="-s -Os"

3) Bug 20649 - [MIPS] Can't find matching LO16 reloc

cd opencv-3.4.9/samples/cpp/example_cmake

make

mips-linux-gnu-g++ example.cpp -o example.o -c -Wall -I/home/zhoudd/2021/202107/cv/opencv-3.4.9/output/include/opencv -I/home/zhoudd/2021/202107/cv/ope

ncv-3.4.9/output/include

mips-linux-gnu-g++ example.o -o opencv_example -L/home/zhoudd/2021/202107/cv/opencv-3.4.9/output/lib -L/home/zhoudd/2021/202107/cv/opencv-3.4.9/output/

share/OpenCV/3rdparty/lib -lopencv_imgcodecs -lopencv_imgproc -lopencv_core -lzlib -littnotify -llibjpeg-turbo -llibjasper -ldl -lm -lpthread -lrt

/opt/mips-gcc540-glibc222-64bit-r3.3.0/bin/../lib/gcc/mips-linux-gnu/5.4.0/../../../../mips-linux-gnu/bin/ld: /home/zhoudd/2021/202107/cv/opencv-3.4.9/

output/lib/libopencv_core.a(ocl.cpp.o): Can't find matching LO16 reloc against `_ZN2cv3oclL5crc64EPKhjy.constprop.345' for R_MIPS_GOT16 at 0x170 in sec

tion `.text._ZN2cv3ocl13ProgramSource4Impl10updateHashEPKc[_ZN2cv3ocl13ProgramSource4Impl10updateHashEPKc]'

fix

https://sourceware.org/bugzilla/show_bug.cgi?id=20649

[1]Building / Cross Compiling OpenCV for Linux ARM

https://www.ridgesolutions.ie/index.php/2013/05/24/building-cross-compiling-opencv-for-linux-arm/

[2]Cross compilation for ARM based Linux systems

https://docs.opencv.org/3.4.13/d0/d76/tutorial_arm_crosscompile_with_cmake.html

[3]海思3559上移植OpenCV3.4.1 (四)在3559A上的适配

https://blog.csdn.net/zhenglie110/article/details/87933483

[4]海思平台OpenCV编译与进一步裁剪

https://zhuanlan.zhihu.com/p/198457743?utm_source=org.mozilla.firefox_beta