1. First, record how to make an interface program with Qt Creator and create a new project
After the above selection
Select the path, enter the project name, and click continue
Select Desktop Qt 5.12.1 GCC 65bit option as follows, and click Details to expand and view
Continue to the following interface
You can refer to my previous blog to design the program interface
Run the program, click the show button on the interface, and the text will appear in the text box
2. Next, record the process of configuring Opencv
https://github.com/opencv/opencv Download the opencv source code package from the website, and the version 3.4 is selected here
Select to download
After downloading, unzip and create a build folder under the folder of CmakeLists.txt
mkdir build
Install the necessary environment libraries with the following command
apt-get install build-essential sudo apt-get install cmake git libgtk2.0-dev pkg-config libavcodec-dev libavformat-dev libswscale-dev
The command line goes to the build folder
cd build
Enter the following command to automatically generate a makefile through the cmakelist file
cmake -D CMAKE_BUILD_TYPE=Release -D CMAKE_INSTALL_PREFIX=/usr/local ..
After that, use the make command to read the corresponding instructions from the makefile, and then compile
make
If an error message appears during the process:
failed to create symbolic link '../../lib/libopencv_core.so.3.4': operation not supported on socket
You can check whether your library is placed in the mount shared directory. If so, you can try to change it to a new location (bloggers have encountered it, just change a non mount folder, and bloggers use the virtual machine environment).
Then execute the following command to install the file generated by make into the corresponding directory of the system
make install
After completion, the following configuration is required:
Enter the following command:
gedit /etc/ld.so.conf.d/opencv.conf
After opening, enter the following
Enter the following command to make the configuration path effective
sudo ldconfig
Then perform bash configuration
sudo gedit /etc/bash.bashrc
Add at the end
PKG_CONFIG_PATH=$PKG_CONFIG_PATH:/usr/local/lib/pkgconfig export PKG_CONFIG_PATH
After saving, execute the following commands to make the configuration effective
source /etc/bash.bashrc
Enter the following command to view the version of opencv
pkg-config opencv --modversion
This completes the configuration.
3. In the first step, add the reference of opencv library to the configuration GUI program
Add the reference path of the header file and lib library to the. pro file
NCLUDEPATH += /usr/local/include \
/usr/local/include/opencv \
/usr/local/include/opencv2
LIBS += /usr/local/lib/libopencv_highgui.so \
/usr/local/lib/libopencv_core.so \
/usr/local/lib/libopencv_imgproc.so \
/usr/local/lib/libopencv_imgcodecs.so
ui interface design is as follows:
The code in manwindow.h is as follows:
#include "mainwindow.h"
#include "ui_mainwindow.h"
#include <opencv2/core/core.hpp>
#include <opencv2/opencv.hpp>
using namespace cv;
MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{
ui->setupUi(this);
}
void MainWindow::slot1()
{
ui->textEdit->setText("hello world!");
Mat img = imread("/home/icecreamshao/108.bmp");
imshow("image", img);
waitKey(0);
Mat temp;
cvtColor(img, temp, CV_BGR2RGB);
QImage Qtemp = QImage((const unsigned char*)(temp.data), temp.cols, temp.rows, temp.step, QImage::Format_RGB888);
ui->label->setPixmap(QPixmap::fromImage(Qtemp));
ui->label->resize(Qtemp.size());
ui->label->show();
}
MainWindow::~MainWindow()
{
delete ui;
}
Run the program and the results are as follows:
