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Forum Update on Monday, May 27th 2025

Combine Multiple Images Into a Single PDF

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  • K koronabora
    29 Jun 2016, 15:22

    Use one of them:

    1. http://podofo.sourceforge.net
    2. https://github.com/pocoproject/poco/tree/master/PDF
    G Offline
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    geor
    wrote on 29 Jun 2016, 18:08 last edited by
    #6

    @koronabora thank you but I prefer not to use 3rd party lib

    1 Reply Last reply
    0
    • 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

      M Offline
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      mrjj
      Lifetime Qt Champion
      wrote on 29 Jun 2016, 18:09 last edited by
      #7

      @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 1 Reply Last reply 30 Jun 2016, 18:23
      4
      • 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

        ? Offline
        ? Offline
        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
          G Offline
          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
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                        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
                              M Offline
                              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
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                                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
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