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  • P Offline
    P Offline
    Payx
    wrote on last edited by
    #61

    I got :

    QColor domicolor=dominantColor(pixi,point,size);
    

    The returned color is "domicolor", so i put domicolor in :

    void fillSection(pixi, point, size, domicolor);
    
    1 Reply Last reply
    2
    • VRoninV Offline
      VRoninV Offline
      VRonin
      wrote on last edited by
      #62

      sooo close!
      http://www.cplusplus.com/doc/tutorial/functions/#void

      "La mort n'est rien, mais vivre vaincu et sans gloire, c'est mourir tous les jours"
      ~Napoleon Bonaparte

      On a crusade to banish setIndexWidget() from the holy land of Qt

      P 1 Reply Last reply
      1
      • VRoninV VRonin

        sooo close!
        http://www.cplusplus.com/doc/tutorial/functions/#void

        P Offline
        P Offline
        Payx
        wrote on last edited by Payx
        #63

        I call her with just :

        fillSection(pixi,point,size,domicolor);
        
        VRoninV 1 Reply Last reply
        3
        • P Payx

          I call her with just :

          fillSection(pixi,point,size,domicolor);
          
          VRoninV Offline
          VRoninV Offline
          VRonin
          wrote on last edited by
          #64

          @Payx Bingo!

          "La mort n'est rien, mais vivre vaincu et sans gloire, c'est mourir tous les jours"
          ~Napoleon Bonaparte

          On a crusade to banish setIndexWidget() from the holy land of Qt

          1 Reply Last reply
          2
          • P Offline
            P Offline
            Payx
            wrote on last edited by
            #65

            I try to change the rectSize with 100 x 100.

            my first function is :

            void MainWindow::on_push_clicked()
            {
            	QString fileName = QFileDialog::getOpenFileName(this,
            	tr("Open Image"), "/", tr("Image Files (*.png *.jpg *.bmp)"));
            	QPixmap pix(fileName);
            	ui->label->setPixmap(pix);
            	const QSize s = pix.size();
            	QImage pixi = QImage(pix.toImage());
            
            	ui->label_2->setText( "Size: " + QString::number(s.width()) +" "+ QString::number(s.height()) );
            
            }
            

            It load an image with an explorer file.

            But the picture dont change at all when i click on the push2

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            0
            • VRoninV Offline
              VRoninV Offline
              VRonin
              wrote on last edited by VRonin
              #66

              I did not say you were done, just that you were on the right path.

              from the code you posted it's clear you did not grasp scoping 100% so i'll repost the link: http://www.cplusplus.com/doc/tutorial/namespaces/#scopes

              pix and pixi die as soon as MainWindow::on_push_clicked() terminates

              "La mort n'est rien, mais vivre vaincu et sans gloire, c'est mourir tous les jours"
              ~Napoleon Bonaparte

              On a crusade to banish setIndexWidget() from the holy land of Qt

              P 1 Reply Last reply
              0
              • VRoninV VRonin

                I did not say you were done, just that you were on the right path.

                from the code you posted it's clear you did not grasp scoping 100% so i'll repost the link: http://www.cplusplus.com/doc/tutorial/namespaces/#scopes

                pix and pixi die as soon as MainWindow::on_push_clicked() terminates

                P Offline
                P Offline
                Payx
                wrote on last edited by
                #67

                @VRonin Yes but in my .h i add QImage pixi thats not correct?

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                • VRoninV Offline
                  VRoninV Offline
                  VRonin
                  wrote on last edited by
                  #68

                  I'm surprised your compiler doesn't yell about redefinition (I probably know why but that's not the point here). I'send you to http://www.cplusplus.com/doc/tutorial/namespaces/#scopes once again

                  "La mort n'est rien, mais vivre vaincu et sans gloire, c'est mourir tous les jours"
                  ~Napoleon Bonaparte

                  On a crusade to banish setIndexWidget() from the holy land of Qt

                  kshegunovK P 2 Replies Last reply
                  0
                  • VRoninV VRonin

                    I'm surprised your compiler doesn't yell about redefinition (I probably know why but that's not the point here). I'send you to http://www.cplusplus.com/doc/tutorial/namespaces/#scopes once again

                    kshegunovK Offline
                    kshegunovK Offline
                    kshegunov
                    Moderators
                    wrote on last edited by
                    #69

                    @VRonin said in Picture:

                    I'm surprised your compiler doesn't yell about redefinition

                    Not redefinition, shadowing, hence no yelling. :)

                    Read and abide by the Qt Code of Conduct

                    VRoninV 1 Reply Last reply
                    2
                    • kshegunovK kshegunov

                      @VRonin said in Picture:

                      I'm surprised your compiler doesn't yell about redefinition

                      Not redefinition, shadowing, hence no yelling. :)

                      VRoninV Offline
                      VRoninV Offline
                      VRonin
                      wrote on last edited by
                      #70

                      @kshegunov said in Picture:

                      shadowing

                      The case @kshegunov is explaining is in the 3rd code block of the link above:

                      // inner block scopes
                      #include <iostream>
                      using namespace std;
                      
                      int main () {
                        int x = 10;
                        int y = 20;
                        {
                          int x;   // ok, inner scope.
                          x = 50;  // sets value to inner x
                          y = 50;  // sets value to (outer) y
                          cout << "inner block:\n";
                          cout << "x: " << x << '\n';
                          cout << "y: " << y << '\n';
                        }
                        cout << "outer block:\n";
                        cout << "x: " << x << '\n';
                        cout << "y: " << y << '\n';
                        return 0;
                      }
                      

                      This means I should go back to that tutorial myself

                      "La mort n'est rien, mais vivre vaincu et sans gloire, c'est mourir tous les jours"
                      ~Napoleon Bonaparte

                      On a crusade to banish setIndexWidget() from the holy land of Qt

                      1 Reply Last reply
                      2
                      • VRoninV VRonin

                        I'm surprised your compiler doesn't yell about redefinition (I probably know why but that's not the point here). I'send you to http://www.cplusplus.com/doc/tutorial/namespaces/#scopes once again

                        P Offline
                        P Offline
                        Payx
                        wrote on last edited by
                        #71

                        @VRonin so if i want use my picture in an other function i have to declare it before my function as i did for

                        QColor dominantColor(const QImage& image, const QPoint& topLeft, const QSize& rectSize);

                        so i have to add a line code QImage pixi in my .cpp ?

                        why not in my .h, and why

                        QColor dominantColor
                        

                        dont work in my .h too ?

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                        0
                        • VRoninV Offline
                          VRoninV Offline
                          VRonin
                          wrote on last edited by
                          #72

                          Ok, this has become too chatty, let's make it more structured before we both get banned.

                          • Put dominantColor and fillSection code from either me or @mrjj at the top of your .cpp file, just below the #includes no need to declare them in advance in this case
                          • in the private: section of your .h file add QImage m_baseImag;
                          • in on_push_clicked load the image from file and store it in m_baseImag then use QPixmap::fromImage(m_baseImag) to display the image in the QLabel
                          • in on_push2_clicked iterate over every 4x4 square of your picture calling the two functions:
                          for (int i=0;i<m_baseImag.width();i+=4){
                                     for (int j=0;j<m_baseImag.height();j+=4){
                          fillSection(m_baseImag,QPoint(i,j),QSize(4,4),dominantColour(m_baseImag,QPoint(i,j),QSize(4,4)));
                          }}
                          
                          • use QPixmap::fromImage(m_baseImag) to display the new image in another QLabel

                          "La mort n'est rien, mais vivre vaincu et sans gloire, c'est mourir tous les jours"
                          ~Napoleon Bonaparte

                          On a crusade to banish setIndexWidget() from the holy land of Qt

                          1 Reply Last reply
                          1
                          • P Offline
                            P Offline
                            Payx
                            wrote on last edited by Payx
                            #73

                            Hello,

                            I have 0 error but it didn't work.

                            here my code

                            void MainWindow::on_push_clicked()
                            {
                            	QString fileName = QFileDialog::getOpenFileName(this,
                            	tr("Open Image"), "/", tr("Image Files (*.png *.jpg *.bmp)"));
                            	QPixmap pix(fileName);
                            	ui->label->setPixmap(pix);
                            	const QSize s = pix.size();
                            	QImage pixi = QImage(pix.toImage());
                            
                            	
                            
                            }
                            
                            void MainWindow::on_push2_clicked()
                            {
                            	QPoint point(0,0);
                            	QSize size(4,4);
                            	for(int i=0;i<pixi.width();i+=4){
                            		for(int j=0;j<pixi.height();j+=4){
                            			fillSection(pixi,point,size,dominantColor(pixi,point,size));
                            		}
                            	}
                            
                            	QPixmap pixa=QPixmap::fromImage(pixi);
                            
                            	ui->label_2->setPixmap(pixa);
                            }
                            

                            In my .h i declared

                            private:
                               Ui::MainWindow *ui;
                               QImage pixi;
                            

                            pixi is the name of my picture (= m_baseImag)

                            i display pixa (Qpix from pixi) in the same label as pixi (dont know if i can do that)

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                            0
                            • mrjjM Offline
                              mrjjM Offline
                              mrjj
                              Lifetime Qt Champion
                              wrote on last edited by
                              #74

                              Hi
                              Good work.
                              in here
                              void MainWindow::on_push_clicked()
                              {
                              ......
                              QImage pixi = QImage(pix.toImage()); // This looks like a local variable? ( die by scope)
                              }

                              Did you mean to use the one from .H ?

                              so
                              pixi = QImage(pix.toImage());

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                              1
                              • P Offline
                                P Offline
                                Payx
                                wrote on last edited by
                                #75

                                i changed my code by using pixi = QImage(pix.toImage());

                                and in my .h i got QImage pixi.

                                I try to fix my rectSize to 15x15

                                And my picture at the end is the same, she changed a little (she got a blue pixel in the top left

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                                0
                                • VRoninV Offline
                                  VRoninV Offline
                                  VRonin
                                  wrote on last edited by
                                  #76

                                  you never update point in your loop. it's always 0,0 it should be i,j

                                  "La mort n'est rien, mais vivre vaincu et sans gloire, c'est mourir tous les jours"
                                  ~Napoleon Bonaparte

                                  On a crusade to banish setIndexWidget() from the holy land of Qt

                                  P 1 Reply Last reply
                                  2
                                  • VRoninV VRonin

                                    you never update point in your loop. it's always 0,0 it should be i,j

                                    P Offline
                                    P Offline
                                    Payx
                                    wrote on last edited by Payx
                                    #77
                                    This post is deleted!
                                    1 Reply Last reply
                                    0
                                    • P Offline
                                      P Offline
                                      Payx
                                      wrote on last edited by
                                      #78

                                      Ok after long hours, i fixed it.

                                      Thank you very much for your time in my project.

                                      But i have a little question :

                                      In the code it only returns Red, Blue or Green.

                                      Do you have a function who return a lot of color, like if in my rect the most principal color is grey (for example) what could i do to add a lot of color ?

                                      At the end i will have a picture more pixelated but that i can recognize

                                      kshegunovK 1 Reply Last reply
                                      0
                                      • mrjjM Offline
                                        mrjjM Offline
                                        mrjj
                                        Lifetime Qt Champion
                                        wrote on last edited by
                                        #79

                                        Hi

                                        • if in my rect the most principal color is grey

                                        That is just values for R,G,B. still.

                                        1 Reply Last reply
                                        1
                                        • VRoninV Offline
                                          VRoninV Offline
                                          VRonin
                                          wrote on last edited by VRonin
                                          #80

                                          Modify dominantColour with this one. It takes the most frequent colour that appears in the square and fills it with it

                                          QColor dominantColour(const QImage& image,const QPoint& topLeft, const QSize& rectSize){
                                          	const int maxRight = qMin(image.width(),topLeft.x() + rectSize.width());
                                          	const int maxBottom = qMin(image.height(),topLeft.y() + rectSize.height());
                                          	QHash<QColor,int> colourMap;
                                          	for(int x=topLeft.x();x<maxRight;++x){
                                          		for(int y=topLeft.y();y<maxBottom;++y){
                                          			const QColor tempColor=image.pixelColor(x,y);
                                          			auto colourIter=colourMap.find(tempColor);
                                          			if(colourIter==colourMap.end())
                                          				colourMap.insert(tempColor,1);
                                          			else
                                          				colourIter.value()++;
                                          		}
                                          	}
                                          	if(colourMap.isEmpty())
                                          		return Qt::black;
                                          	return std::max_element(colourMap.constBegin(),colourMap.constEnd()).key();
                                          }
                                          

                                          "La mort n'est rien, mais vivre vaincu et sans gloire, c'est mourir tous les jours"
                                          ~Napoleon Bonaparte

                                          On a crusade to banish setIndexWidget() from the holy land of Qt

                                          1 Reply Last reply
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