跳到內容
  • 版面
  • 最新
  • 標籤
  • 熱門
  • 使用者
  • 群組
  • 搜尋
  • Get Qt Extensions
  • Unsolved
Collapse
品牌標誌
  1. 首頁
  2. Qt Development
  3. General and Desktop
  4. Picture
Forum Updated to NodeBB v4.3 + New Features

Picture

已排程 已置頂 已鎖定 已移動 Solved General and Desktop
82 貼文 7 Posters 46.4k 瀏覽 3 Watching
  • 從舊到新
  • 從新到舊
  • 最多點贊
回覆
  • 在新貼文中回覆
登入後回覆
此主題已被刪除。只有擁有主題管理權限的使用者可以查看。
  • VRoninV VRonin

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

    P 離線
    P 離線
    Payx
    寫於 最後由 Payx 編輯
    #63

    I call her with just :

    fillSection(pixi,point,size,domicolor);
    
    VRoninV 1 條回覆 最後回覆
    3
    • P Payx

      I call her with just :

      fillSection(pixi,point,size,domicolor);
      
      VRoninV 離線
      VRoninV 離線
      VRonin
      寫於 最後由 編輯
      #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 條回覆 最後回覆
      2
      • P 離線
        P 離線
        Payx
        寫於 最後由 編輯
        #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

        1 條回覆 最後回覆
        0
        • VRoninV 離線
          VRoninV 離線
          VRonin
          寫於 最後由 VRonin 編輯
          #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 條回覆 最後回覆
          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 離線
            P 離線
            Payx
            寫於 最後由 編輯
            #67

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

            1 條回覆 最後回覆
            0
            • VRoninV 離線
              VRoninV 離線
              VRonin
              寫於 最後由 編輯
              #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 條回覆 最後回覆
              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 離線
                kshegunovK 離線
                kshegunov
                Moderators
                寫於 最後由 編輯
                #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 條回覆 最後回覆
                2
                • kshegunovK kshegunov

                  @VRonin said in Picture:

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

                  Not redefinition, shadowing, hence no yelling. :)

                  VRoninV 離線
                  VRoninV 離線
                  VRonin
                  寫於 最後由 編輯
                  #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 條回覆 最後回覆
                  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 離線
                    P 離線
                    Payx
                    寫於 最後由 編輯
                    #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 ?

                    1 條回覆 最後回覆
                    0
                    • VRoninV 離線
                      VRoninV 離線
                      VRonin
                      寫於 最後由 編輯
                      #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 條回覆 最後回覆
                      1
                      • P 離線
                        P 離線
                        Payx
                        寫於 最後由 Payx 編輯
                        #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)

                        1 條回覆 最後回覆
                        0
                        • mrjjM 離線
                          mrjjM 離線
                          mrjj
                          Lifetime Qt Champion
                          寫於 最後由 編輯
                          #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());

                          1 條回覆 最後回覆
                          1
                          • P 離線
                            P 離線
                            Payx
                            寫於 最後由 編輯
                            #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

                            1 條回覆 最後回覆
                            0
                            • VRoninV 離線
                              VRoninV 離線
                              VRonin
                              寫於 最後由 編輯
                              #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 條回覆 最後回覆
                              2
                              • VRoninV VRonin

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

                                P 離線
                                P 離線
                                Payx
                                寫於 最後由 Payx 編輯
                                #77
                                此回覆已被刪除!
                                1 條回覆 最後回覆
                                0
                                • P 離線
                                  P 離線
                                  Payx
                                  寫於 最後由 編輯
                                  #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 條回覆 最後回覆
                                  0
                                  • mrjjM 離線
                                    mrjjM 離線
                                    mrjj
                                    Lifetime Qt Champion
                                    寫於 最後由 編輯
                                    #79

                                    Hi

                                    • if in my rect the most principal color is grey

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

                                    1 條回覆 最後回覆
                                    1
                                    • VRoninV 離線
                                      VRoninV 離線
                                      VRonin
                                      寫於 最後由 VRonin 編輯
                                      #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 條回覆 最後回覆
                                      1
                                      • P Payx

                                        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 離線
                                        kshegunovK 離線
                                        kshegunov
                                        Moderators
                                        寫於 最後由 編輯
                                        #81

                                        I suggest you average the color in the rectangle, e.g. (thanks to @VRonin for the scaffolding):

                                        QColor dominantColour(const QImage & image,const QPoint & topLeft, const QSize & rectSize)
                                        {
                                            qint32 averageRed = 0, averageGreen = 0, averageBlue = 0;
                                        
                                            const qint32 maxX = qMin<qint32>(image.width(), topLeft.x() + rectSize.width());
                                            const qint32 maxY = qMin<qint32>(image.height(), topLeft.y() + rectSize.height());
                                            for (qint32 y = topLeft.y(); y < maxY; y++)  {
                                                for (qint32 x = topLeft.x(); x < maxX; x++)   {
                                                    QRgb pixel = image.pixel(x, y);
                                                    
                                                    averageRed += qRed(pixel);
                                                    averageGreen += qGreen(pixel);
                                                    averageBlue += qBlue(pixel);
                                                }
                                            }
                                        
                                            qint32 n = rectSize.width() * rectSize.height();
                                        
                                            Q_ASSERT(n);
                                            if (n <= 0)
                                                return Qt::black;
                                        
                                            return QColor(averageRed / n, averageGreen / n, averageBlue / n);
                                        }
                                        

                                        Read and abide by the Qt Code of Conduct

                                        1 條回覆 最後回覆
                                        1
                                        • P 離線
                                          P 離線
                                          Payx
                                          寫於 最後由 編輯
                                          #82

                                          Thank you very much !

                                          1 條回覆 最後回覆
                                          0

                                          • 登入

                                          • Login or register to search.
                                          • 第一個貼文
                                            最後的貼文
                                          0
                                          • 版面
                                          • 最新
                                          • 標籤
                                          • 熱門
                                          • 使用者
                                          • 群組
                                          • 搜尋
                                          • Get Qt Extensions
                                          • Unsolved