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Forum Update on Monday, May 27th 2025

Combine Multiple Images Into a Single PDF

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pdfsavewidget
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  • G geor
    29 Jun 2016, 18:02

    @Wieland I took a look at the functions for that class and all I see is way to edit the pages but how do you add the images?

    thank you

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    A Former User
    wrote on 29 Jun 2016, 18:26 last edited by
    #8

    @geor Like this:

    void writePdf()
    {
        const QString fileName("/home/patrick/mydoc.pdf");
        const QImage image("/home/patrick/truck.jpg");
        const QPoint imageCoordinates(0,0);
    
        QPdfWriter pdfWriter(fileName);
        pdfWriter.setPageSize(QPageSize(QPageSize::A4));
        QPainter painter(&pdfWriter);
    
        for (int i=0; i<3; ++i) {
            painter.drawImage(imageCoordinates, image);
            pdfWriter.newPage();
        }
    }
    
    G 1 Reply Last reply 30 Jun 2016, 18:28
    6
    • M mrjj
      29 Jun 2016, 18:09

      @geor
      Hi
      You draw the images to it.
      http://www.codeprogress.com/cpp/libraries/qt/showQtExample.php?index=570&key=QPdfWriterWriteImage

      Keep in mind about DPI.

      G Offline
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      geor
      wrote on 30 Jun 2016, 18:23 last edited by
      #9

      @mrjj thank you

      1 Reply Last reply
      0
      • ? A Former User
        29 Jun 2016, 18:26

        @geor Like this:

        void writePdf()
        {
            const QString fileName("/home/patrick/mydoc.pdf");
            const QImage image("/home/patrick/truck.jpg");
            const QPoint imageCoordinates(0,0);
        
            QPdfWriter pdfWriter(fileName);
            pdfWriter.setPageSize(QPageSize(QPageSize::A4));
            QPainter painter(&pdfWriter);
        
            for (int i=0; i<3; ++i) {
                painter.drawImage(imageCoordinates, image);
                pdfWriter.newPage();
            }
        }
        
        G Offline
        G Offline
        geor
        wrote on 30 Jun 2016, 18:28 last edited by
        #10

        @Wieland thank you

        ? 1 Reply Last reply 30 Jun 2016, 18:29
        0
        • G geor
          30 Jun 2016, 18:28

          @Wieland thank you

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          A Former User
          wrote on 30 Jun 2016, 18:29 last edited by
          #11

          @geor :-)

          G 1 Reply Last reply 20 Jul 2016, 19:53
          1
          • ? A Former User
            30 Jun 2016, 18:29

            @geor :-)

            G Offline
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            geor
            wrote on 20 Jul 2016, 19:53 last edited by
            #12

            @Wieland I keep getting qpainter::begin() reutnr false

            I am even using your exact code

                    const QString fileName("C:/Qt");
            const QImage image("C:/Users/georg/Desktop/testPdf/Untitled.jpg");
            const QPoint imageCoordinates(0,0);
            
            QPdfWriter pdfWriter(fileName);
            pdfWriter.setPageSize(QPagedPaintDevice::A1);
            QPainter painter(&pdfWriter);
            
            for (int i=0; i<3; ++i)
            {
                painter.drawImage(imageCoordinates, image);
                pdfWriter.newPage();
                qDebug()<<2;
            }
            

            except for the page size becuase I am using qt 5.2.1

            do you have any idea why ebcuase I cannot figure it out the debug still runs i just get the eror and it does not save

            M 1 Reply Last reply 20 Jul 2016, 20:07
            1
            • G geor
              20 Jul 2016, 19:53

              @Wieland I keep getting qpainter::begin() reutnr false

              I am even using your exact code

                      const QString fileName("C:/Qt");
              const QImage image("C:/Users/georg/Desktop/testPdf/Untitled.jpg");
              const QPoint imageCoordinates(0,0);
              
              QPdfWriter pdfWriter(fileName);
              pdfWriter.setPageSize(QPagedPaintDevice::A1);
              QPainter painter(&pdfWriter);
              
              for (int i=0; i<3; ++i)
              {
                  painter.drawImage(imageCoordinates, image);
                  pdfWriter.newPage();
                  qDebug()<<2;
              }
              

              except for the page size becuase I am using qt 5.2.1

              do you have any idea why ebcuase I cannot figure it out the debug still runs i just get the eror and it does not save

              M Offline
              M Offline
              mrjj
              Lifetime Qt Champion
              wrote on 20 Jul 2016, 20:07 last edited by
              #13

              @geor said:

              const QString fileName("C:/Qt");

              that is the actual filename ?

              I would expect something like
              const QString fileName("c:/mydoc.pdf");

              G 1 Reply Last reply 20 Jul 2016, 20:51
              2
              • ? Offline
                ? Offline
                A Former User
                wrote on 20 Jul 2016, 20:08 last edited by
                #14

                To add to what @mrjj said, do you have write access to C:/?

                G 2 Replies Last reply 20 Jul 2016, 20:57
                3
                • M mrjj
                  20 Jul 2016, 20:07

                  @geor said:

                  const QString fileName("C:/Qt");

                  that is the actual filename ?

                  I would expect something like
                  const QString fileName("c:/mydoc.pdf");

                  G Offline
                  G Offline
                  geor
                  wrote on 20 Jul 2016, 20:51 last edited by
                  #15

                  @mrjj said:

                  @
                  I still get the same error

                  M 1 Reply Last reply 20 Jul 2016, 21:04
                  0
                  • ? A Former User
                    20 Jul 2016, 20:08

                    To add to what @mrjj said, do you have write access to C:/?

                    G Offline
                    G Offline
                    geor
                    wrote on 20 Jul 2016, 20:57 last edited by
                    #16
                    This post is deleted!
                    1 Reply Last reply
                    0
                    • ? A Former User
                      20 Jul 2016, 20:08

                      To add to what @mrjj said, do you have write access to C:/?

                      G Offline
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                      geor
                      wrote on 20 Jul 2016, 21:03 last edited by
                      #17

                      @Wieland

                      once again thank you for your help it worked when I switch to the drive where the build is saved .However for some reason it is 4 empty pages maybe it's becuase of the size or something I'll try another image and see but again thank you

                      M 1 Reply Last reply 20 Jul 2016, 21:04
                      0
                      • G geor
                        20 Jul 2016, 20:51

                        @mrjj said:

                        @
                        I still get the same error

                        M Offline
                        M Offline
                        mrjj
                        Lifetime Qt Champion
                        wrote on 20 Jul 2016, 21:04 last edited by
                        #18

                        @geor
                        I think its just a path thing

                        void writePdf()
                        {
                            const QString fileName("e:/mydoc.pdf");
                               QPdfWriter pdfWriter(fileName);
                            pdfWriter.setPageSize(QPageSize(QPageSize::A4));
                            QPainter painter(&pdfWriter);
                        
                            for (int i=0; i<3; ++i) {
                                painter.drawPixmap(QRect(0,0,pdfWriter.logicalDpiX()*8.3,pdfWriter.logicalDpiY()*11.7), QPixmap("e:/truck.png"));
                                pdfWriter.newPage();
                            }
                        }
                        
                        works here. makes PDF on e:
                        
                        1 Reply Last reply
                        2
                        • G geor
                          20 Jul 2016, 21:03

                          @Wieland

                          once again thank you for your help it worked when I switch to the drive where the build is saved .However for some reason it is 4 empty pages maybe it's becuase of the size or something I'll try another image and see but again thank you

                          M Offline
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                          mrjj
                          Lifetime Qt Champion
                          wrote on 20 Jul 2016, 21:04 last edited by
                          #19

                          @geor
                          hi
                          You will / might need to scale the picture or its really small.

                          G 2 Replies Last reply 21 Jul 2016, 18:05
                          1
                          • M mrjj
                            20 Jul 2016, 21:04

                            @geor
                            hi
                            You will / might need to scale the picture or its really small.

                            G Offline
                            G Offline
                            geor
                            wrote on 21 Jul 2016, 18:05 last edited by
                            #20

                            @mrjj

                            yeh it worked after scaling thank you.

                            1 Reply Last reply
                            1
                            • M mrjj
                              20 Jul 2016, 21:04

                              @geor
                              hi
                              You will / might need to scale the picture or its really small.

                              G Offline
                              G Offline
                              geor
                              wrote on 21 Jul 2016, 21:10 last edited by
                              #21

                              @mrjj one more question lol

                              the size of my widget is too big to fit well on a A4 paper without looking deformed. So I want to break the layout of it's parent, resize my widget it and then take it's pixmap to put it in an A4 so it is not deformed (with the grab function) but the problem is I can't break the layout of the parent i can only delete (in code) and when I delete it it deletes everything in it any tips?

                              M 1 Reply Last reply 21 Jul 2016, 21:13
                              0
                              • G geor
                                21 Jul 2016, 21:10

                                @mrjj one more question lol

                                the size of my widget is too big to fit well on a A4 paper without looking deformed. So I want to break the layout of it's parent, resize my widget it and then take it's pixmap to put it in an A4 so it is not deformed (with the grab function) but the problem is I can't break the layout of the parent i can only delete (in code) and when I delete it it deletes everything in it any tips?

                                M Offline
                                M Offline
                                mrjj
                                Lifetime Qt Champion
                                wrote on 21 Jul 2016, 21:13 last edited by mrjj
                                #22

                                @geor
                                Hi you can use the takeAt method to get your widget back from a layout.
                                But maybe you can just ask the widget to render directly?
                                it has a render function that can draw itself to anything you like.
                                http://doc.qt.io/qt-5/qwidget.html#render

                                G 1 Reply Last reply 22 Jul 2016, 14:44
                                3
                                • M mrjj
                                  21 Jul 2016, 21:13

                                  @geor
                                  Hi you can use the takeAt method to get your widget back from a layout.
                                  But maybe you can just ask the widget to render directly?
                                  it has a render function that can draw itself to anything you like.
                                  http://doc.qt.io/qt-5/qwidget.html#render

                                  G Offline
                                  G Offline
                                  geor
                                  wrote on 22 Jul 2016, 14:44 last edited by
                                  #23

                                  @mrjj

                                  it doesn't seem to chnage much unless I am using it wrong? here is my code 1870 and 994 is the size of my widget.making the pixmap the same as the size of my widget gives me excatly the same ouput as before so i made it smaller it's better but cuts most of the widget out

                                                     ui->page1->setBackgroundRole(QPalette::BrightText);
                                  
                                               QPixmap pixMap1(600,900);
                                             ui->page1->render(&pixMap1,QPoint(),QRegion(0,0,1870,994));
                                  
                                  
                                  
                                  
                                      const QString fileName("D:/mydoc2.pdf");
                                         QPdfWriter pdfWriter(fileName);
                                      pdfWriter.setPageSize(QPagedPaintDevice::A4);
                                      QPainter painter(&pdfWriter);
                                  
                                     
                                          painter.drawPixmap(QRect(0,0,pdfWriter.logicalDpiX()*8.3,pdfWriter.logicalDpiY()*11.7), pixMap1);
                                          pdfWriter.newPage();
                                  
                                  M 1 Reply Last reply 22 Jul 2016, 17:53
                                  1
                                  • G geor
                                    22 Jul 2016, 14:44

                                    @mrjj

                                    it doesn't seem to chnage much unless I am using it wrong? here is my code 1870 and 994 is the size of my widget.making the pixmap the same as the size of my widget gives me excatly the same ouput as before so i made it smaller it's better but cuts most of the widget out

                                                       ui->page1->setBackgroundRole(QPalette::BrightText);
                                    
                                                 QPixmap pixMap1(600,900);
                                               ui->page1->render(&pixMap1,QPoint(),QRegion(0,0,1870,994));
                                    
                                    
                                    
                                    
                                        const QString fileName("D:/mydoc2.pdf");
                                           QPdfWriter pdfWriter(fileName);
                                        pdfWriter.setPageSize(QPagedPaintDevice::A4);
                                        QPainter painter(&pdfWriter);
                                    
                                       
                                            painter.drawPixmap(QRect(0,0,pdfWriter.logicalDpiX()*8.3,pdfWriter.logicalDpiY()*11.7), pixMap1);
                                            pdfWriter.newPage();
                                    
                                    M Offline
                                    M Offline
                                    mrjj
                                    Lifetime Qt Champion
                                    wrote on 22 Jul 2016, 17:53 last edited by
                                    #24

                                    @geor
                                    hi
                                    Sorry, didn't read the right docs.
                                    The rect is for clipping not resize the widget.
                                    So render will not help you to render it smaller.

                                    so yes, i guess to render it in different size, you must take widget out , call resize +render and put it back it.
                                    Not sure how well it will work if there is other stuff in the layout.
                                    If sole widget, it should work ok.

                                    G 1 Reply Last reply 25 Jul 2016, 15:38
                                    1
                                    • M mrjj
                                      22 Jul 2016, 17:53

                                      @geor
                                      hi
                                      Sorry, didn't read the right docs.
                                      The rect is for clipping not resize the widget.
                                      So render will not help you to render it smaller.

                                      so yes, i guess to render it in different size, you must take widget out , call resize +render and put it back it.
                                      Not sure how well it will work if there is other stuff in the layout.
                                      If sole widget, it should work ok.

                                      G Offline
                                      G Offline
                                      geor
                                      wrote on 25 Jul 2016, 15:38 last edited by
                                      #25

                                      @mrjj Yeah I tried this method and It works but it's not perfect even if I resize the widget to the size of an A4 and then take it's pixmap fore some reason in the pdf it loses some quality (it looks a lot better in the user interface then in the pdf )even tho they are both the same size.I tried different functions from the painter class to draw the pixamp but the all seam the same not so good .If I draw the pixmap withouth any scaling it is very small in the pdf .. any ideas?

                                      M 1 Reply Last reply 25 Jul 2016, 16:55
                                      0
                                      • G geor
                                        25 Jul 2016, 15:38

                                        @mrjj Yeah I tried this method and It works but it's not perfect even if I resize the widget to the size of an A4 and then take it's pixmap fore some reason in the pdf it loses some quality (it looks a lot better in the user interface then in the pdf )even tho they are both the same size.I tried different functions from the painter class to draw the pixamp but the all seam the same not so good .If I draw the pixmap withouth any scaling it is very small in the pdf .. any ideas?

                                        M Offline
                                        M Offline
                                        mrjj
                                        Lifetime Qt Champion
                                        wrote on 25 Jul 2016, 16:55 last edited by
                                        #26

                                        @geor
                                        hi , have you tried to render it really large and then
                                        scale down to fit A4?

                                        G 1 Reply Last reply 25 Jul 2016, 17:45
                                        0
                                        • M mrjj
                                          25 Jul 2016, 16:55

                                          @geor
                                          hi , have you tried to render it really large and then
                                          scale down to fit A4?

                                          G Offline
                                          G Offline
                                          geor
                                          wrote on 25 Jul 2016, 17:45 last edited by
                                          #27

                                          @mrjj yep no matter how large the pixmap awlays appears very small on the pdf

                                          M 1 Reply Last reply 25 Jul 2016, 17:48
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