How to setup Qt and openCV on Windows

From Qt Wiki
Revision as of 19:23, 7 March 2017 by Cdwijs (talk | contribs) (Removed instructions for old versions, cleaned up instructions for the latest versions)
Jump to navigation Jump to search

How to setup Qt and openCV on Windows

Introduction

This article shows how to install Qt, build OpenCV, and run a basic OpenCV example. This article assumes Windows 7 has just been installed.

This procedure requires close to 10GB of disk space: 

Qt: 5.06GB
opencv: 522MB
opencv-Build: 3.95GB
downloads:152MB

This article uses information from the following pages: http://docs.opencv.org/2.4/doc/tutorials/introduction/windows_install/windows_install.html?highlight=installation http://www.laganiere.name/opencvCookbook/chap1s1_2.shtml

Windows 7, Qt 5.8, OpenCV 3.2.0

Qt

Installation

Download the Qt installer from www.qt.io, then choose "Download now". This will then download qt-unified-windows-x86-2.0.5-online.exe. Execute the program, then choose the following settings: 

 Welcome to the Qt online installer: next
 Qt Account - your unified login to everything Qt: skip
 Setup-Qt: next
 installation folder: D:\Qt
 select components: Qt-Qt5.8-MingGW 5.3.0 32 bit
 select components: Qt-Tools-MinGW 5.3.0
 License Agreement: agree and next
 start menu shortcuts: next
 ready to install: install

Testing

Run D:\Qt\Tools\QtCreator\bin\qtcreator.exe 

 File-New file or project-Qt Widgets Application-choose
 enter a name and a location: next
 select all kits: next
 Class information: MainWindow (defaults): Next
 Project management: Finish

Now a new project is made. Start debugging by choosing 

 Debug-Start Debugging-Start debugging (F5)

Now the Qt tab in the windows task bar should turn into a progress bar. After some time a new empty window should pop up. Stop debugging either by pressing the red cross in the top right of this new window, or choose 

 Debug-Stop debugging

Adjust Qt

When you need to add, remove or update a component of Qt, this can be done by running D:\Qt\MaintenanceTool.exe: 

 maintain Qt: Qt Account: Skip
 Setup Qt: Add or remove components: Next
 Select components: 
 next :update

Tortoisegit

Todo

Cmake

Download cmake from cmake.org. In this guide, 3.7.2 is used. Start cmake-3.7.2-win64-x64.msi, then choose the following settinge: 

 Welcome to the CMake etup Wizzard: next
 End-User License Agreement: [X] Accept and next
 Install options: [X] Add CMake to the system PATH for all users, next
 Destination folder: C:\Program Files\CMake (default), next
 Ready to install CMake, Install

OpenCV

Getting OpenCV

Download openCV from sourceforge. In this guide, version 3.2.0 is used. Start opencv-3.2.0-vc14.exe and let it extract to d:\ . Now the folder d:\opencv is created.

Add minGW to the windows PATH variable

Open the control panel, 
System and Security, 
System, 
Advanced system settings,
Environment Variables,
System Variables,
Variable Name: Path
Variable value: ;D:\Qt\Tools\mingw530_32\bin

Compiling OpenCV

Start C:\Program Files\CMake\bin\cmake-gui.exe then choose the following settings: 

 Where is the source code: D:/opencv/sources
 where to build the binaries: D:\opencv-build

Then click Configure, let cmake create the build directory, and choose the following settings: 

 Specify the generator for this project: MinGW Makefiles
 Specify native compilers, next
 Compilers C: D:/Qt/Tools/mingw530_32/bin/gcc.exe
 Compilers C++: D:/Qt/Tools/mingw530_32/bin/g++.exe
 Finish

 Check the box [X]WITH_QT

Then click configure again 

 Set CMAKE_BUILD_TYPE to Release or RelWithDebInfo
 Set Qt5Core_DIR to D:\Qt\5.8\mingw53_32\lib\cmake\Qt5Core
 Set Qt5Concurrent_DIR D:\Qt\5.8\mingw53_32\lib\cmake\Qt5Concurrent
 Set Qt5Core_DIR D:\Qt\5.8\mingw53_32\lib\cmake\Qt5Core
 Set Qt5Gui_DIR D:\Qt\5.8\mingw53_32\lib\cmake\Qt5Gui
 Set Qt5Test_DIR D:\Qt\5.8\mingw53_32\lib\cmake\Qt5Test
 Set Qt5Widgets_DIR D:\Qt\5.8\mingw53_32\lib\cmake\Qt5Widgets

Then click configure again Then click generate

Next open cmd, and type the following commands. To speed up the compile, the -j flag can be used to run multiple compile jobs simultaneously. On an 8 core CPU, you can set it to 8 or higher, so all cores are used. 

 d:
 cd d:\
 cd opencv-build  
 mingw32-make -j 8
 mingw32-make install

Add OpenCV compiled libraries to the windows PATH variable

Open the control panel, 
System and Security, 
System, 
Advanced system settings,
Environment Variables,
System Variables,
Variable Name: Path
Variable value: ;D:\opencv-build\install\x86\mingw\bin

Compile and run the example

Run D:\Qt\Tools\QtCreator\bin\qtcreator.exe 

 File-New file or project-Qt Widgets Application-choose
 enter a name and a location: next
 select all kits: next
 Class information: MainWindow (defaults): Next
 Project management: Finish

Now a new project is made.

modify the .pro file like this: 

#-------------------------------------------------
#
# Project created by QtCreator 2017-03-05T12:30:06
#
#-------------------------------------------------

QT       += core gui

greaterThan(QT_MAJOR_VERSION, 4): QT += widgets

TARGET = untitled
TEMPLATE = app

# The following define makes your compiler emit warnings if you use
# any feature of Qt which as been marked as deprecated (the exact warnings
# depend on your compiler). Please consult the documentation of the
# deprecated API in order to know how to port your code away from it.
DEFINES += QT_DEPRECATED_WARNINGS

# You can also make your code fail to compile if you use deprecated APIs.
# In order to do so, uncomment the following line.
# You can also select to disable deprecated APIs only up to a certain version of Qt.
#DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000    # disables all the APIs deprecated before Qt 6.0.0


SOURCES += main.cpp\
        mainwindow.cpp

HEADERS  += mainwindow.h

FORMS    += mainwindow.ui

INCLUDEPATH += D:\opencv-build\install\include
LIBS += -LD:\opencv-build\install\x86\mingw\lib \
    -lopencv_core320.dll \
    -lopencv_highgui320.dll \
    -lopencv_imgcodecs320.dll \
    -lopencv_imgproc320.dll \
    -lopencv_features2d320.dll \
    -lopencv_calib3d320.dll

and modify mainwindow.cpp like this: 

#include "mainwindow.h"
#include "ui_mainwindow.h"

#include <opencv2/core/core.hpp>
#include <opencv2/highgui/highgui.hpp>
/*
#include <opencv2/core/core.hpp>
#include <opencv2/highgui/highgui.hpp>*/

MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);

    // read an image
    cv::Mat image = cv::imread("f://1.jpg" , 1 );
    // create image window named "My Image"
    cv::namedWindow("My Image");
    // show the image on window
    cv::imshow("My Image", image);
}

MainWindow::~MainWindow()
{
    delete ui;
}

Place an imag with the name "1.img" in the root of f:\, then run the example. Now 2 windows should pop up. One with the image, and one with an empty window.

Retrieved from "https://wiki.qt.io/index.php?title=How_to_setup_Qt_and_openCV_on_Windows&oldid=30236"