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Declaration of function and use it

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  • jsulmJ jsulm

    @gauravsharma0190 Where is this function declared? In which header file? "function not declared" means the function is not known. You have to make it visible including the header file. It is the same story as in C.

    G Offline
    G Offline
    gauravsharma0190
    wrote on last edited by
    #30

    @jsulm
    Here i am sending you my all code.
    **

    • /////main.cpp///**
      #include "mainwindow.h"
      #include <QApplication>
      #include<QSplashScreen>
      #include<QTimer>
      #include<opencv2/highgui/highgui.hpp>
      #include<opencv2/core/core.hpp>
      #include<opencv2/opencv.hpp>
      using namespace cv;
      using namespace std;
      int main(int argc, char *argv[])
      {

      QApplication a(argc, argv);
      QSplashScreen *splash =new QSplashScreen;
      splash->setPixmap(QPixmap("/home/pi/Desktop/ceeri1.jpg"));
      splash->show();

      MainWindow w;
      QTimer::singleShot(3500,splash,SLOT(close()));

      QTimer::singleShot(3500,&w,SLOT(show()));

      //w.show();

      return a.exec();
      }
      ////mainwindow.h
      #ifndef MAINWINDOW_H
      #define MAINWINDOW_H

    #include <QMainWindow>
    //using namespace cv;
    namespace Ui {
    class MainWindow;
    }

    class MainWindow : public QMainWindow
    {
    Q_OBJECT

    public:
    explicit MainWindow(QWidget *parent = 0);
    ~MainWindow();

    private slots:
    void showTime();

    void on_pushButton_5_clicked();
    

    void onTrackball_clicked(int,void*);

    private:
    Ui::MainWindow *ui;
    };

    #endif // MAINWINDOW_H
    ///mainwindow.c

    #include "mainwindow.h"
    #include "ui_mainwindow.h"
    #include<opencv2/opencv.hpp>
    #include <opencv2/highgui/highgui.hpp>
    #include <opencv2/core/core.hpp>
    #include<QFileDialog>
    #include<QMessageBox>
    #include <iostream>
    #include <string>
    #include <fstream>
    #include<time.h>
    #include<QTimer>
    #include<QDateTime>
    using namespace cv;
    using namespace std;
    MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
    {
    ui->setupUi(this);
    QTimer *timer=new QTimer(this);
    connect(timer,SIGNAL(timeout()),this,SLOT(showTime()));
    timer->start();
    QDateTime dateTime=QDateTime::currentDateTime();
    QString datetimetext=dateTime.toString();
    ui->DateTime->setText(datetimetext);

    }
    ////////Time///////////////
    void MainWindow:: showTime()
    {
    QTime time=QTime::currentTime();
    QString time_text=time.toString("hh : mm : ss");
    if((time.second() % 2)==0)
    {
    time_text[3] =' ';
    time_text[8] =' ';
    }
    ui->Digital->setText(time_text);

    }

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

    void MainWindow::on_pushButton_4_clicked()
    {

    }

    void MainWindow::on_pushButton_5_clicked()
    {
    QString filename=QFileDialog::getOpenFileName(
    this,
    tr("Open file") ,
    "/home/pi/Desktop",
    tr("All files(*.png *.jpg)"));

    QMessageBox::information(this,tr("Filename"),filename);
    if(QString::compare(filename,QString())!=0)
    {
        QImage image;
        bool valid=image.load(filename);
        if(valid)
        {
            image=image.scaledToWidth(ui->Picture->width(),Qt::SmoothTransformation);
            ui->Picture->setPixmap(QPixmap::fromImage(image));
    
        }
    

    void MainWindow::onTrackball_clicked(int,void*)
    {
    //Here wite the all function//
    ///Now how to put this code in this.

    ////////This is the code i have to input in this push button////
    Mat src, src_gray;
    Mat dst, detected_edges;

    int edgeThresh = 1;
    int lowThreshold;
    int const max_lowThreshold = 100;
    int ratio = 3;
    int kernel_size = 3;
    char* window_name = "Edge Map";

    /**

    @function CannyThreshold
    @brief Trackbar callback - Canny thresholds input with a ratio 1:3
    /
    void CannyThreshold(int, void)
    {
    /// Reduce noise with a kernel 3x3
    blur( src_gray, detected_edges, Size(3,3) );
    /// Canny detector
    Canny( detected_edges, detected_edges, lowThreshold, lowThreshold*ratio, kernel_size );

    /// Using Canny's output as a mask, we display our result
    dst = Scalar::all(0);

    src.copyTo( dst, detected_edges);
    imshow( window_name, dst );
    }

    /** @function main /
    int main( int argc, char* argv )
    {
    /// Load an image
    src = imread( argv[1] );

    if( !src.data )
    { return -1; }

    /// Create a matrix of the same type and size as src (for dst)
    dst.create( src.size(), src.type() );

    /// Convert the image to grayscale
    cvtColor( src, src_gray, CV_BGR2GRAY );

    /// Create a window
    namedWindow( window_name, CV_WINDOW_AUTOSIZE );

    /// Create a Trackbar for user to enter threshold
    createTrackbar( "Min Threshold:", window_name, &lowThreshold, max_lowThreshold, CannyThreshold );

    /// Show the image
    CannyThreshold(0, 0);

    /// Wait until user exit program by pressing a key
    waitKey(0);

    return 0;
    }

    }
    }
    
    1 Reply Last reply
    0
    • jsulmJ Offline
      jsulmJ Offline
      jsulm
      Lifetime Qt Champion
      wrote on last edited by
      #31

      Sorry, but the code you posted is invalid C/C++! First of all: why do you have 2 main functions?
      Why did you put other functions inside void MainWindow::onTrackball_clicked(int,void*)? This is not going to compile and I'm not going to fix it for you. How familiar are you actually with C/C++?
      What you have to do is: do not put the C function definitions inside void MainWindow::onTrackball_clicked(int,void*), instead put them inside another source code file and header, include the header file in MainWindow and then call the functions in void MainWindow::onTrackball_clicked(int,void*). As an alternative you can have those C functions in MainWindow.cpp but not inside void MainWindow::onTrackball_clicked(int,void*) !

      https://forum.qt.io/topic/113070/qt-code-of-conduct

      G 1 Reply Last reply
      1
      • jsulmJ jsulm

        Sorry, but the code you posted is invalid C/C++! First of all: why do you have 2 main functions?
        Why did you put other functions inside void MainWindow::onTrackball_clicked(int,void*)? This is not going to compile and I'm not going to fix it for you. How familiar are you actually with C/C++?
        What you have to do is: do not put the C function definitions inside void MainWindow::onTrackball_clicked(int,void*), instead put them inside another source code file and header, include the header file in MainWindow and then call the functions in void MainWindow::onTrackball_clicked(int,void*). As an alternative you can have those C functions in MainWindow.cpp but not inside void MainWindow::onTrackball_clicked(int,void*) !

        G Offline
        G Offline
        gauravsharma0190
        wrote on last edited by
        #32

        @jsulm
        i don't put these function definition inside voidmainwindow::ontrackball
        but i am asking you how can i call that function inside my void mainwindow::ontrackball

        void CannyThreshold(int, void)
        {
        /// Reduce noise with a kernel 3x3
        blur( src_gray, detected_edges, Size(3,3) );
        /// Canny detector
        Canny( detected_edges, detected_edges, lowThreshold, lowThreshold*ratio, kernel_size );
        
        /// Using Canny's output as a mask, we display our result
        dst = Scalar::all(0);
        
        src.copyTo( dst, detected_edges);
        imshow( window_name, dst );
        }
        

        Mean i hyave done .cpp and .h file of this and include in my code both.

        jsulmJ 2 Replies Last reply
        0
        • G gauravsharma0190

          @jsulm
          i don't put these function definition inside voidmainwindow::ontrackball
          but i am asking you how can i call that function inside my void mainwindow::ontrackball

          void CannyThreshold(int, void)
          {
          /// Reduce noise with a kernel 3x3
          blur( src_gray, detected_edges, Size(3,3) );
          /// Canny detector
          Canny( detected_edges, detected_edges, lowThreshold, lowThreshold*ratio, kernel_size );
          
          /// Using Canny's output as a mask, we display our result
          dst = Scalar::all(0);
          
          src.copyTo( dst, detected_edges);
          imshow( window_name, dst );
          }
          

          Mean i hyave done .cpp and .h file of this and include in my code both.

          jsulmJ Offline
          jsulmJ Offline
          jsulm
          Lifetime Qt Champion
          wrote on last edited by
          #33

          @gauravsharma0190 Like this?

          CannyThreshold(1, nullptr);
          

          So, what exactly is the problem?
          In the code you posted you DID put these function definitions inside void MainWindow::onTrackball_clicked(int,void*) (just check what you posted).

          https://forum.qt.io/topic/113070/qt-code-of-conduct

          1 Reply Last reply
          0
          • G gauravsharma0190

            @jsulm
            i don't put these function definition inside voidmainwindow::ontrackball
            but i am asking you how can i call that function inside my void mainwindow::ontrackball

            void CannyThreshold(int, void)
            {
            /// Reduce noise with a kernel 3x3
            blur( src_gray, detected_edges, Size(3,3) );
            /// Canny detector
            Canny( detected_edges, detected_edges, lowThreshold, lowThreshold*ratio, kernel_size );
            
            /// Using Canny's output as a mask, we display our result
            dst = Scalar::all(0);
            
            src.copyTo( dst, detected_edges);
            imshow( window_name, dst );
            }
            

            Mean i hyave done .cpp and .h file of this and include in my code both.

            jsulmJ Offline
            jsulmJ Offline
            jsulm
            Lifetime Qt Champion
            wrote on last edited by
            #34

            @gauravsharma0190 Shouldn't

            void CannyThreshold(int, void)
            

            be

            void CannyThreshold(int, void*)
            

            ?

            https://forum.qt.io/topic/113070/qt-code-of-conduct

            G 1 Reply Last reply
            0
            • G Offline
              G Offline
              gauravsharma0190
              wrote on last edited by
              #35

              ok now i will send you refresh code just wait.
              Thank you.
              i will send you refresh code and errors.

              1 Reply Last reply
              0
              • jsulmJ jsulm

                @gauravsharma0190 Shouldn't

                void CannyThreshold(int, void)
                

                be

                void CannyThreshold(int, void*)
                

                ?

                G Offline
                G Offline
                gauravsharma0190
                wrote on last edited by
                #36

                @jsulm
                hey here is the code i have done with that.
                /////main.cpp////

                #include<opencv2/highgui/highgui.hpp>
                #include<opencv2/core/core.hpp>
                #include<opencv2/opencv.hpp>
                using namespace cv;
                using namespace std;
                int main(int argc, char *argv[])
                {
                
                    QApplication a(argc, argv);
                    QSplashScreen *splash =new QSplashScreen;
                    splash->setPixmap(QPixmap("/home/pi/Desktop/ceeri1.jpg"));
                    splash->show();
                
                    MainWindow w;
                    QTimer::singleShot(3500,splash,SLOT(close()));
                
                    QTimer::singleShot(3500,&w,SLOT(show()));
                
                  //w.show();
                
                    return a.exec();
                }
                

                ///mainwindow.h///

                #ifndef MAINWINDOW_H
                #define MAINWINDOW_H
                
                #include <QMainWindow>
                //using namespace cv;
                namespace Ui {
                class MainWindow;
                }
                
                class MainWindow : public QMainWindow
                {
                Q_OBJECT
                
                public:
                explicit MainWindow(QWidget *parent = 0);
                ~MainWindow();
                
                private slots:
                void showTime();
                
                void on_pushButton_5_clicked();
                void onTrackball_clicked(int,void*);
                
                private:
                Ui::MainWindow *ui;
                };
                
                #endif // MAINWINDOW_H
                

                ///ontrack.h///

                #ifndef __ONTRACK_h
                #define __ONTRACK_h
                void cannyThresold(int,void*);
                #endif
                

                ///ontrack.cpp

                #include "ontrack.h"
                #include<opencv2/opencv.hpp>
                #include <opencv2/highgui/highgui.hpp>
                #include <opencv2/core/core.hpp>
                void CannyThreshold(int, void)
                {
                /// Reduce noise with a kernel 3x3
                blur( src_gray, detected_edges, Size(3,3) );
                /// Canny detector
                Canny( detected_edges, detected_edges, lowThreshold, lowThreshold*ratio, kernel_size );
                
                /// Using Canny's output as a mask, we display our result
                dst = Scalar::all(0);
                
                src.copyTo( dst, detected_edges);
                imshow( window_name, dst );
                }
                

                //Here Comes Mainwindow.cpp///

                #include "ui_mainwindow.h"
                #include<opencv2/opencv.hpp>
                #include <opencv2/highgui/highgui.hpp>
                #include <opencv2/core/core.hpp>
                #include "ontrack.h"
                #include<QFileDialog>
                #include<QMessageBox>
                #include <iostream>
                #include <string>
                #include <fstream>
                #include<time.h>
                #include<QTimer>
                #include<QDateTime>
                using namespace cv;
                using namespace std;
                MainWindow::MainWindow(QWidget *parent) :
                QMainWindow(parent),
                ui(new Ui::MainWindow)
                {
                ui->setupUi(this);
                QTimer *timer=new QTimer(this);
                connect(timer,SIGNAL(timeout()),this,SLOT(showTime()));
                timer->start();
                QDateTime dateTime=QDateTime::currentDateTime();
                QString datetimetext=dateTime.toString();
                ui->DateTime->setText(datetimetext);
                
                }
                ////////Time///////////////
                void MainWindow:: showTime()
                {
                QTime time=QTime::currentTime();
                QString time_text=time.toString("hh : mm : ss");
                if((time.second() % 2)==0)
                {
                time_text[3] =' ';
                time_text[8] =' ';
                }
                ui->Digital->setText(time_text);
                
                }
                
                MainWindow::~MainWindow()
                {
                delete ui;
                }
                
                void MainWindow::on_pushButton_4_clicked()
                {
                
                }
                
                void MainWindow::on_pushButton_5_clicked()
                {
                QString filename=QFileDialog::getOpenFileName(
                this,
                tr("Open file") ,
                "/home/pi/Desktop",
                tr("All files(*.png *.jpg)"));
                
                QMessageBox::information(this,tr("Filename"),filename);
                if(QString::compare(filename,QString())!=0)
                {
                    QImage image;
                    bool valid=image.load(filename);
                    if(valid)
                    {
                        image=image.scaledToWidth(ui->Picture->width(),Qt::SmoothTransformation);
                        ui->Picture->setPixmap(QPixmap::fromImage(image));
                
                    }
                void MainWindow::onTrackball_clicked(int,void*)
                {
                
                
                Mat src, src_gray;
                Mat dst, detected_edges;
                
                int edgeThresh = 1;
                int lowThreshold;
                int const max_lowThreshold = 100;
                int ratio = 3;
                int kernel_size = 3;
                char* window_name = "Edge Map";
                
                
                
                @function CannyThreshold
                @brief Trackbar callback - Canny thresholds input with a ratio 1:3
                /
                
                
                /// Load an image
                src = imread( argv[1] );
                
                if( !src.data )
                { return -1; }
                
                /// Create a matrix of the same type and size as src (for dst)
                dst.create( src.size(), src.type() );
                
                /// Convert the image to grayscale
                cvtColor( src, src_gray, CV_BGR2GRAY );
                
                /// Create a window
                namedWindow( window_name, CV_WINDOW_AUTOSIZE );
                
                /// Create a Trackbar for user to enter threshold
                createTrackbar( "Min Threshold:", window_name, &lowThreshold, max_lowThreshold, CannyThreshold );
                
                /// Show the image
                CannyThreshold(0, 0);
                
                }
                }
                ...
                But error occurs defination of function outside the class.
                G 1 Reply Last reply
                0
                • G gauravsharma0190

                  @jsulm
                  hey here is the code i have done with that.
                  /////main.cpp////

                  #include<opencv2/highgui/highgui.hpp>
                  #include<opencv2/core/core.hpp>
                  #include<opencv2/opencv.hpp>
                  using namespace cv;
                  using namespace std;
                  int main(int argc, char *argv[])
                  {
                  
                      QApplication a(argc, argv);
                      QSplashScreen *splash =new QSplashScreen;
                      splash->setPixmap(QPixmap("/home/pi/Desktop/ceeri1.jpg"));
                      splash->show();
                  
                      MainWindow w;
                      QTimer::singleShot(3500,splash,SLOT(close()));
                  
                      QTimer::singleShot(3500,&w,SLOT(show()));
                  
                    //w.show();
                  
                      return a.exec();
                  }
                  

                  ///mainwindow.h///

                  #ifndef MAINWINDOW_H
                  #define MAINWINDOW_H
                  
                  #include <QMainWindow>
                  //using namespace cv;
                  namespace Ui {
                  class MainWindow;
                  }
                  
                  class MainWindow : public QMainWindow
                  {
                  Q_OBJECT
                  
                  public:
                  explicit MainWindow(QWidget *parent = 0);
                  ~MainWindow();
                  
                  private slots:
                  void showTime();
                  
                  void on_pushButton_5_clicked();
                  void onTrackball_clicked(int,void*);
                  
                  private:
                  Ui::MainWindow *ui;
                  };
                  
                  #endif // MAINWINDOW_H
                  

                  ///ontrack.h///

                  #ifndef __ONTRACK_h
                  #define __ONTRACK_h
                  void cannyThresold(int,void*);
                  #endif
                  

                  ///ontrack.cpp

                  #include "ontrack.h"
                  #include<opencv2/opencv.hpp>
                  #include <opencv2/highgui/highgui.hpp>
                  #include <opencv2/core/core.hpp>
                  void CannyThreshold(int, void)
                  {
                  /// Reduce noise with a kernel 3x3
                  blur( src_gray, detected_edges, Size(3,3) );
                  /// Canny detector
                  Canny( detected_edges, detected_edges, lowThreshold, lowThreshold*ratio, kernel_size );
                  
                  /// Using Canny's output as a mask, we display our result
                  dst = Scalar::all(0);
                  
                  src.copyTo( dst, detected_edges);
                  imshow( window_name, dst );
                  }
                  

                  //Here Comes Mainwindow.cpp///

                  #include "ui_mainwindow.h"
                  #include<opencv2/opencv.hpp>
                  #include <opencv2/highgui/highgui.hpp>
                  #include <opencv2/core/core.hpp>
                  #include "ontrack.h"
                  #include<QFileDialog>
                  #include<QMessageBox>
                  #include <iostream>
                  #include <string>
                  #include <fstream>
                  #include<time.h>
                  #include<QTimer>
                  #include<QDateTime>
                  using namespace cv;
                  using namespace std;
                  MainWindow::MainWindow(QWidget *parent) :
                  QMainWindow(parent),
                  ui(new Ui::MainWindow)
                  {
                  ui->setupUi(this);
                  QTimer *timer=new QTimer(this);
                  connect(timer,SIGNAL(timeout()),this,SLOT(showTime()));
                  timer->start();
                  QDateTime dateTime=QDateTime::currentDateTime();
                  QString datetimetext=dateTime.toString();
                  ui->DateTime->setText(datetimetext);
                  
                  }
                  ////////Time///////////////
                  void MainWindow:: showTime()
                  {
                  QTime time=QTime::currentTime();
                  QString time_text=time.toString("hh : mm : ss");
                  if((time.second() % 2)==0)
                  {
                  time_text[3] =' ';
                  time_text[8] =' ';
                  }
                  ui->Digital->setText(time_text);
                  
                  }
                  
                  MainWindow::~MainWindow()
                  {
                  delete ui;
                  }
                  
                  void MainWindow::on_pushButton_4_clicked()
                  {
                  
                  }
                  
                  void MainWindow::on_pushButton_5_clicked()
                  {
                  QString filename=QFileDialog::getOpenFileName(
                  this,
                  tr("Open file") ,
                  "/home/pi/Desktop",
                  tr("All files(*.png *.jpg)"));
                  
                  QMessageBox::information(this,tr("Filename"),filename);
                  if(QString::compare(filename,QString())!=0)
                  {
                      QImage image;
                      bool valid=image.load(filename);
                      if(valid)
                      {
                          image=image.scaledToWidth(ui->Picture->width(),Qt::SmoothTransformation);
                          ui->Picture->setPixmap(QPixmap::fromImage(image));
                  
                      }
                  void MainWindow::onTrackball_clicked(int,void*)
                  {
                  
                  
                  Mat src, src_gray;
                  Mat dst, detected_edges;
                  
                  int edgeThresh = 1;
                  int lowThreshold;
                  int const max_lowThreshold = 100;
                  int ratio = 3;
                  int kernel_size = 3;
                  char* window_name = "Edge Map";
                  
                  
                  
                  @function CannyThreshold
                  @brief Trackbar callback - Canny thresholds input with a ratio 1:3
                  /
                  
                  
                  /// Load an image
                  src = imread( argv[1] );
                  
                  if( !src.data )
                  { return -1; }
                  
                  /// Create a matrix of the same type and size as src (for dst)
                  dst.create( src.size(), src.type() );
                  
                  /// Convert the image to grayscale
                  cvtColor( src, src_gray, CV_BGR2GRAY );
                  
                  /// Create a window
                  namedWindow( window_name, CV_WINDOW_AUTOSIZE );
                  
                  /// Create a Trackbar for user to enter threshold
                  createTrackbar( "Min Threshold:", window_name, &lowThreshold, max_lowThreshold, CannyThreshold );
                  
                  /// Show the image
                  CannyThreshold(0, 0);
                  
                  }
                  }
                  ...
                  But error occurs defination of function outside the class.
                  G Offline
                  G Offline
                  gauravsharma0190
                  wrote on last edited by
                  #37

                  @gauravsharma0190 said:

                  Sorry in ontrack.cpp i again add
                  Mat src, src_gray;
                  Mat dst, detected_edges;

                  jsulmJ 2 Replies Last reply
                  0
                  • G gauravsharma0190

                    @gauravsharma0190 said:

                    Sorry in ontrack.cpp i again add
                    Mat src, src_gray;
                    Mat dst, detected_edges;

                    jsulmJ Offline
                    jsulmJ Offline
                    jsulm
                    Lifetime Qt Champion
                    wrote on last edited by
                    #38

                    @gauravsharma0190 Can you post the whole error message?
                    Why do you have int and void* parameter in onTrackball_clicked which you do not use?

                    https://forum.qt.io/topic/113070/qt-code-of-conduct

                    1 Reply Last reply
                    1
                    • G gauravsharma0190

                      @gauravsharma0190 said:

                      Sorry in ontrack.cpp i again add
                      Mat src, src_gray;
                      Mat dst, detected_edges;

                      jsulmJ Offline
                      jsulmJ Offline
                      jsulm
                      Lifetime Qt Champion
                      wrote on last edited by
                      #39

                      @gauravsharma0190 Take a look at this:

                      
                      void MainWindow::on_pushButton_5_clicked()
                      {
                      QString filename=QFileDialog::getOpenFileName(
                      this,
                      tr("Open file") ,
                      "/home/pi/Desktop",
                      tr("All files(*.png *.jpg)"));
                      
                      QMessageBox::information(this,tr("Filename"),filename);
                      if(QString::compare(filename,QString())!=0)
                      {
                          QImage image;
                          bool valid=image.load(filename);
                          if(valid)
                          {
                              image=image.scaledToWidth(ui->Picture->width(),Qt::SmoothTransformation);
                              ui->Picture->setPixmap(QPixmap::fromImage(image));
                      
                          }
                      void MainWindow::onTrackball_clicked(int,void*)
                      {
                      

                      void MainWindow::onTrackball_clicked(int,void*) is inside void MainWindow::on_pushButton_5_clicked() - this is invalid!

                      https://forum.qt.io/topic/113070/qt-code-of-conduct

                      G 1 Reply Last reply
                      1
                      • jsulmJ jsulm

                        @gauravsharma0190 Take a look at this:

                        
                        void MainWindow::on_pushButton_5_clicked()
                        {
                        QString filename=QFileDialog::getOpenFileName(
                        this,
                        tr("Open file") ,
                        "/home/pi/Desktop",
                        tr("All files(*.png *.jpg)"));
                        
                        QMessageBox::information(this,tr("Filename"),filename);
                        if(QString::compare(filename,QString())!=0)
                        {
                            QImage image;
                            bool valid=image.load(filename);
                            if(valid)
                            {
                                image=image.scaledToWidth(ui->Picture->width(),Qt::SmoothTransformation);
                                ui->Picture->setPixmap(QPixmap::fromImage(image));
                        
                            }
                        void MainWindow::onTrackball_clicked(int,void*)
                        {
                        

                        void MainWindow::onTrackball_clicked(int,void*) is inside void MainWindow::on_pushButton_5_clicked() - this is invalid!

                        G Offline
                        G Offline
                        gauravsharma0190
                        wrote on last edited by
                        #40

                        @jsulm
                        but i am not defining ontrack_clicked in push button its different.

                        mrjjM 1 Reply Last reply
                        0
                        • G gauravsharma0190

                          @jsulm
                          but i am not defining ontrack_clicked in push button its different.

                          mrjjM Offline
                          mrjjM Offline
                          mrjj
                          Lifetime Qt Champion
                          wrote on last edited by
                          #41

                          @gauravsharma0190

                          Are you sure ?
                          it really, really looks like you do :)

                          G 1 Reply Last reply
                          1
                          • mrjjM mrjj

                            @gauravsharma0190

                            Are you sure ?
                            it really, really looks like you do :)

                            G Offline
                            G Offline
                            gauravsharma0190
                            wrote on last edited by
                            #42

                            @mrjj
                            sir i again improving it.
                            as

                            void MainWindow::on_pushButton_6_clicked()
                            {
                               /* Mat src , dst;
                            
                            
                             //   char* source_window = "Source image";
                               // char* equalized_window = "Equalized Image";
                            
                                /// Load image
                                src = imread( "/home/pi/Desktop/b4.jpg" );
                            
                            
                            
                                /// Convert to grayscale
                                cvtColor( src, src, CV_BGR2GRAY );
                            
                                /// Apply Histogram Equalization
                                equalizeHist( src, dst );
                            
                                /// Display results
                                namedWindow( "source", CV_WINDOW_NORMAL );
                                namedWindow( "equalized", CV_WINDOW_NORMAL );
                            
                                imshow( "source", src );
                                imshow( "equalized", dst );
                            
                                /// Wait until user exits the program
                              //  waitKey(0);*/
                            
                            
                            
                                Mat src_base, hsv_base;
                                Mat src_test1, hsv_test1;
                                Mat src_test2, hsv_test2;
                                Mat hsv_half_down;
                            
                                /// Load three images with different environment settings
                            
                                src_base = imread( "/home/pi/Desktop/b4.jpg" );
                                src_test1 = imread( "/home/pi/Desktop/b4.jpg" );
                                src_test2 = imread( "/home/pi/Desktop/b3.jpg" );
                            
                                /// Convert to HSV
                                cvtColor( src_base, hsv_base, COLOR_BGR2HSV );
                                cvtColor( src_test1, hsv_test1, COLOR_BGR2HSV );
                                cvtColor( src_test2, hsv_test2, COLOR_BGR2HSV );
                            
                                hsv_half_down = hsv_base( Range( hsv_base.rows/2, hsv_base.rows - 1 ), Range( 0, hsv_base.cols - 1 ) );
                            
                                /// Using 50 bins for hue and 60 for saturation
                                int h_bins = 50; int s_bins = 60;
                                int histSize[] = { h_bins, s_bins };
                            
                                // hue varies from 0 to 179, saturation from 0 to 255
                                float h_ranges[] = { 0, 180 };
                                float s_ranges[] = { 0, 256 };
                            
                                const float* ranges[] = { h_ranges, s_ranges };
                            
                                // Use the o-th and 1-st channels
                                int channels[] = { 0, 1 };
                            
                            
                                /// Histograms
                                MatND hist_base;
                                MatND hist_half_down;
                                MatND hist_test1;
                                MatND hist_test2;
                            
                                /// Calculate the histograms for the HSV images
                                calcHist( &hsv_base, 1, channels, Mat(), hist_base, 2, histSize, ranges, true, false );
                                normalize( hist_base, hist_base, 0, 1, NORM_MINMAX, -1, Mat() );
                            
                                calcHist( &hsv_half_down, 1, channels, Mat(), hist_half_down, 2, histSize, ranges, true, false );
                                normalize( hist_half_down, hist_half_down, 0, 1, NORM_MINMAX, -1, Mat() );
                            
                                calcHist( &hsv_test1, 1, channels, Mat(), hist_test1, 2, histSize, ranges, true, false );
                                normalize( hist_test1, hist_test1, 0, 1, NORM_MINMAX, -1, Mat() );
                            
                                calcHist( &hsv_test2, 1, channels, Mat(), hist_test2, 2, histSize, ranges, true, false );
                                normalize( hist_test2, hist_test2, 0, 1, NORM_MINMAX, -1, Mat() );
                            
                                /// Apply the histogram comparison methods
                                for( int i = 0; i < 4; i++ )
                                {
                                    int compare_method = i;
                                    double base_base = compareHist( hist_base, hist_base, compare_method );
                                    double base_half = compareHist( hist_base, hist_half_down, compare_method );
                                    double base_test1 = compareHist( hist_base, hist_test1, compare_method );
                                    double base_test2 = compareHist( hist_base, hist_test2, compare_method );
                            
                                    printf( " Method [%d] Perfect, Base-Half, Base-Test(1), Base-Test(2) : %f, %f, %f, %f \n", i, base_base, base_half , base_test1, base_test2 );
                                }
                            
                            
                            
                            
                                }
                            
                            
                            
                            void MainWindow::on_onTrackball_clicked()
                            {
                            
                                Mat src, src_gray;
                                Mat dst, detected_edges;
                            
                                int edgeThresh = 1;
                                int lowThreshold;
                                int const max_lowThreshold = 100;
                                int ratio = 3;
                                int kernel_size = 3;
                                char* window_name = "Edge Map";
                            
                            
                            
                                /// Load image
                                src = imread( "/home/pi/Desktop/b4.jpg");
                                 /// Create a matrix of the same type and size as src (for dst)
                            
                            
                            
                                dst.create( src.size(), src.type() );
                            
                                /// Convert the image to grayscale
                                cvtColor( src, src_gray, CV_BGR2GRAY );
                            
                                /// Create a window
                                namedWindow( window_name, CV_WINDOW_NORMAL );
                            
                                /// Create a Trackbar for user to enter threshold
                              //  createTrackbar( "Min Threshold:", window_name, &lowThreshold, max_lowThreshold, CannyThreshold );
                            
                                /// Show the image
                                CannyThreshold(0, 0);
                            
                            
                                /// Separate the image in 3 places ( B, G and R )
                                vector<Mat> bgr_planes;
                                split( src, bgr_planes );
                            
                                /// Establish the number of bins
                                int histSize = 256;
                            
                                /// Set the ranges ( for B,G,R) )
                                float range[] = { 0, 256 } ;
                                const float* histRange = { range };
                            
                                bool uniform = true;
                                bool accumulate = false;
                            
                                Mat b_hist, g_hist, r_hist;
                            
                                /// Compute the histograms:
                                calcHist( &bgr_planes[0], 1, 0, Mat(), b_hist, 1, &histSize, &histRange, uniform, accumulate );
                                calcHist( &bgr_planes[1], 1, 0, Mat(), g_hist, 1, &histSize, &histRange, uniform, accumulate );
                                calcHist( &bgr_planes[2], 1, 0, Mat(), r_hist, 1, &histSize, &histRange, uniform, accumulate );
                            
                                // Draw the histograms for B, G and R
                                int hist_w = 512; int hist_h = 400;
                               int bin_w = cvRound( (double) hist_w/histSize );
                            
                                Mat histImage( hist_h, hist_w, CV_8UC3, Scalar( 0,0,0) );
                            
                                /// Normalize the result to [ 0, histImage.rows ]
                                normalize(b_hist, b_hist, 0, histImage.rows, NORM_MINMAX, -1, Mat() );
                                normalize(g_hist, g_hist, 0, histImage.rows, NORM_MINMAX, -1, Mat() );
                                normalize(r_hist, r_hist, 0, histImage.rows, NORM_MINMAX, -1, Mat() );
                            
                                /// Draw for each channel
                                for( int i = 1; i < histSize; i++ )
                                {
                                    line( histImage, Point( bin_w*(i-1), hist_h - cvRound(b_hist.at<float>(i-1)) ) ,
                                                     Point( bin_w*(i), hist_h - cvRound(b_hist.at<float>(i)) ),
                                                     Scalar( 255, 0, 0), 2, 8, 0  );
                                    line( histImage, Point( bin_w*(i-1), hist_h - cvRound(g_hist.at<float>(i-1)) ) ,
                                                     Point( bin_w*(i), hist_h - cvRound(g_hist.at<float>(i)) ),
                                                     Scalar( 0, 255, 0), 2, 8, 0  );
                                    line( histImage, Point( bin_w*(i-1), hist_h - cvRound(r_hist.at<float>(i-1)) ) ,
                                                     Point( bin_w*(i), hist_h - cvRound(r_hist.at<float>(i)) ),
                                                     Scalar( 0, 0, 255), 2, 8, 0  );
                                }
                            
                                /// Display
                                namedWindow("calcHist Demo", CV_WINDOW_AUTOSIZE );
                                imshow("calcHist Demo", histImage );
                              imwrite("calcHist Demo2.jpg", histImage);
                                waitKey(-1);
                            
                            
                              }
                            
                            
                            ...
                            This is new improved code .but there are error or build issue
                            1.In member function'void mainwindow::on_on_trackball_clicked()
                            ****canny Thresol was not declered in this scope .(function which i declare and define in .h and .c file.
                            unsed variable 'edgeThresh'.
                            1 Reply Last reply
                            0
                            • mrjjM Offline
                              mrjjM Offline
                              mrjj
                              Lifetime Qt Champion
                              wrote on last edited by
                              #43

                              @gauravsharma0190 said:

                              CannyThreshold

                              this function ?
                              CannyThreshold
                              that you call with
                              CannyThreshold(0, 0);

                              and you do include the .h file where its defined?

                              G 1 Reply Last reply
                              0
                              • mrjjM mrjj

                                @gauravsharma0190 said:

                                CannyThreshold

                                this function ?
                                CannyThreshold
                                that you call with
                                CannyThreshold(0, 0);

                                and you do include the .h file where its defined?

                                G Offline
                                G Offline
                                gauravsharma0190
                                wrote on last edited by
                                #44

                                @mrjj
                                it is defined as

                                ///ontrack.h///
                                
                                #ifndef __ONTRACK_h
                                #define __ONTRACK_h
                                void cannyThresold(int,void*);
                                #endif
                                ......
                                
                                ///ontrack.cpp
                                #include "ontrack.h"
                                #include<opencv2/opencv.hpp>
                                #include <opencv2/highgui/highgui.hpp>
                                #include <opencv2/core/core.hpp>
                                void CannyThreshold(int, void*)
                                {
                                /// Reduce noise with a kernel 3x3
                                blur( src_gray, detected_edges, Size(3,3) );
                                /// Canny detector
                                Canny( detected_edges, detected_edges, lowThreshold, lowThreshold*ratio, kernel_size );
                                
                                /// Using Canny's output as a mask, we display our result
                                dst = Scalar::all(0);
                                
                                src.copyTo( dst, detected_edges);
                                imshow( window_name, dst );
                                }
                                

                                .....
                                thus i include ontrack.h in mainwindow.cpp code.
                                but error occurs.
                                Why??
                                i can't understand.

                                jsulmJ 1 Reply Last reply
                                0
                                • mrjjM Offline
                                  mrjjM Offline
                                  mrjj
                                  Lifetime Qt Champion
                                  wrote on last edited by
                                  #45

                                  I dont understand either.
                                  Seems fine.
                                  try to define a test function
                                  as in
                                  ontrack.h
                                  void mytest();
                                  and call that from main.

                                  If that is still not known, it means that mainwinow do not really include ontrack.h for some reason.

                                  1 Reply Last reply
                                  0
                                  • G gauravsharma0190

                                    @mrjj
                                    it is defined as

                                    ///ontrack.h///
                                    
                                    #ifndef __ONTRACK_h
                                    #define __ONTRACK_h
                                    void cannyThresold(int,void*);
                                    #endif
                                    ......
                                    
                                    ///ontrack.cpp
                                    #include "ontrack.h"
                                    #include<opencv2/opencv.hpp>
                                    #include <opencv2/highgui/highgui.hpp>
                                    #include <opencv2/core/core.hpp>
                                    void CannyThreshold(int, void*)
                                    {
                                    /// Reduce noise with a kernel 3x3
                                    blur( src_gray, detected_edges, Size(3,3) );
                                    /// Canny detector
                                    Canny( detected_edges, detected_edges, lowThreshold, lowThreshold*ratio, kernel_size );
                                    
                                    /// Using Canny's output as a mask, we display our result
                                    dst = Scalar::all(0);
                                    
                                    src.copyTo( dst, detected_edges);
                                    imshow( window_name, dst );
                                    }
                                    

                                    .....
                                    thus i include ontrack.h in mainwindow.cpp code.
                                    but error occurs.
                                    Why??
                                    i can't understand.

                                    jsulmJ Offline
                                    jsulmJ Offline
                                    jsulm
                                    Lifetime Qt Champion
                                    wrote on last edited by
                                    #46

                                    @gauravsharma0190 You call it like this CannyThreshold(0, 0); and in ontrack.cpp it is defined like void CannyThreshold(int, void*). But in ontrack.h it is void cannyThresold(int,void*); please fix the name of the function.

                                    https://forum.qt.io/topic/113070/qt-code-of-conduct

                                    mrjjM G 2 Replies Last reply
                                    1
                                    • jsulmJ jsulm

                                      @gauravsharma0190 You call it like this CannyThreshold(0, 0); and in ontrack.cpp it is defined like void CannyThreshold(int, void*). But in ontrack.h it is void cannyThresold(int,void*); please fix the name of the function.

                                      mrjjM Offline
                                      mrjjM Offline
                                      mrjj
                                      Lifetime Qt Champion
                                      wrote on last edited by
                                      #47

                                      @jsulm
                                      heh Good spotted. completely missed "old" :)

                                      G 1 Reply Last reply
                                      1
                                      • mrjjM mrjj

                                        @jsulm
                                        heh Good spotted. completely missed "old" :)

                                        G Offline
                                        G Offline
                                        gauravsharma0190
                                        wrote on last edited by
                                        #48

                                        @mrjj
                                        I fix canny as Canny in .h file
                                        but again error occurs.

                                        1 Reply Last reply
                                        0
                                        • jsulmJ jsulm

                                          @gauravsharma0190 You call it like this CannyThreshold(0, 0); and in ontrack.cpp it is defined like void CannyThreshold(int, void*). But in ontrack.h it is void cannyThresold(int,void*); please fix the name of the function.

                                          G Offline
                                          G Offline
                                          gauravsharma0190
                                          wrote on last edited by
                                          #49

                                          @jsulm
                                          Hey i fixed it .But again error.

                                          jsulmJ 1 Reply Last reply
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