【关键内容】

1.将opencv编译为能在arm上运行的库

2.在没有板子的情况下，仿真验证opencv库

1.将opencv编译为能在arm上运行的库

1.在下方链接中选择某个版本

Releases - OpenCVhttps://opencv.org/releases/点击“Sources”即可开始下载，得到opencv-3.4.1.zip：

2.解压，得到opencv-3.4.1到/home/ubuntu/opencv/opencv-3.4.1/

unzip opencv-3.4.1.zip

3.打开cmake-gui：

cd opencv-3.4.1
mkdir build
cd build
cmake-gui&

4.

where is the source code：刚下载解压后的opencv-3.4.1的路径

where to build the binaries：刚下载解压后的opencv-3.4.1的路径中的build

然后点击Configure

5.Operation System必须为Linux，Processor必须为arm

Compilers的C为自己PC/服务器中的C交叉编译工具链所在位置

Compilers的C++为自己PC/服务器中的C++交叉编译工具链所在位置

Target Root为自己PC/服务器公用头文件所在位置

Include Mode为Search only in Target Root

点击Finish

6.等到Configuring done

勾选BUILD_JPEG和BUILD_PNG

另外CMAKE_INSTALL_PREFIX也重新选择一下：

7.再次点击Configure，等待Configuring done，点击Generate，等待Generating done，可以关闭cmake-gui了

8.在/home/ubuntu/opencv/opencv-3.4.1/build中运行make -j32，等待100%，然后执行sudo make install，无报错即完成opencv arm交叉编译，所有的编程成果物都在刚才设置好的CMAKE_INSTALL_PREFIX中

2.仿真验证

1.在没有arm板的情况下，在PC/服务器上做仿真验证：

sudo apt-get install qemu

编写main.cpp

#include "opencv2/core.hpp"
#include "opencv2/imgproc.hpp"
#include "opencv2/highgui.hpp"
#include "opencv2/videoio.hpp"
#include <iostream>
#include <stdio.h>
using namespace cv;
using namespace std;


int main()
{
	Mat image;
	image = imread("test.jpg");
	return 0;
}

2.编写Makefile

SRCS += $(wildcard main.cpp)
OBJS = $(SRCS:.cpp = .o)
CXX = arm-linux-gnueabihf-g++
TARGET = exam
INCLUDES = -I/home/ubuntu/output/include/
LIBS = -L.
LIBS += -L/home/ubuntu/output/lib/
CCFLAGS = -Wall -O0

all : $(TARGET)

$(TARGET):$(OBJS)
	$(CXX) $^ -o $@ $(INCLUDES) $(LIBS) -lopencv_stitching -lopencv_videostab -lopencv_objdetect -lopencv_photo -lopencv_dnn -lopencv_calib3d -lopencv_features2d -lopencv_flann -lopencv_highgui -lopencv_ml -lopencv_superres -lopencv_videoio -lopencv_imgcodecs -lopencv_shape -lopencv_video -lopencv_imgproc -lopencv_core -ldl -lm -lpthread -lrt
%.o:%.cpp
	$(CXX) -c $< $(CCFLAGS)
clean:
	rm $(TARGET)

3.编译

make

4.将/home/ubuntu/output/lib/所有文件复制到/usr/lib/下，然后执行

qemu-arm -L /usr/arm-linux-gnueabihf/ ./exam

执行无报错 即完成