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Load Image From Db Problem

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loading imagesdatabaseproblem
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  • M4RZB4NiM M4RZB4Ni

    @mrjj
    no!
    seMcode is true because i can select more data with it !
    i think problem is converting from table(IMAGE DATATYPE) TO byte array !
    and i write your qdebug code and says query ok!

    VRoninV Offline
    VRoninV Offline
    VRonin
    wrote on last edited by
    #13

    @M4RZB4Ni said in Load Image From Db Problem:

    i think problem is converting from table(IMAGE DATATYPE) TO byte array !

    are you using image as field type in your database? if so you shouldn't, it's deprecated and will be removed (see https://msdn.microsoft.com/en-us/library/ms187993.aspx). use varbinary(max) instead.

    Also, you should use QImage instead of QPixmap.

    Qt provides four classes for handling image data: QImage, QPixmap, QBitmap and QPicture. QImage is designed and optimized for I/O, and for direct pixel access and manipulation, while QPixmap is designed and optimized for showing images on screen. QBitmap is only a convenience class that inherits QPixmap, ensuring a depth of 1. Finally, the QPicture class is a paint device that records and replays QPainter commands.

    "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

    M4RZB4NiM 1 Reply Last reply
    1
    • VRoninV VRonin

      @M4RZB4Ni said in Load Image From Db Problem:

      i think problem is converting from table(IMAGE DATATYPE) TO byte array !

      are you using image as field type in your database? if so you shouldn't, it's deprecated and will be removed (see https://msdn.microsoft.com/en-us/library/ms187993.aspx). use varbinary(max) instead.

      Also, you should use QImage instead of QPixmap.

      Qt provides four classes for handling image data: QImage, QPixmap, QBitmap and QPicture. QImage is designed and optimized for I/O, and for direct pixel access and manipulation, while QPixmap is designed and optimized for showing images on screen. QBitmap is only a convenience class that inherits QPixmap, ensuring a depth of 1. Finally, the QPicture class is a paint device that records and replays QPainter commands.

      M4RZB4NiM Offline
      M4RZB4NiM Offline
      M4RZB4Ni
      wrote on last edited by
      #14

      @VRonin
      yes i use IMAGE because when i use VABBINARY(MAX) when i want save image
      program show error
      "Cant Convert varchar datatype to VARBINARY(MAX)!
      and i should Use IMAGE datatype!

      Thanks
      M4RZB4Ni

      1 Reply Last reply
      0
      • VRoninV Offline
        VRoninV Offline
        VRonin
        wrote on last edited by VRonin
        #15

        How do you save it?

        You should definitely use VARBINARY:

        From Microsoft, page linked above:

        IMPORTANT! ntext, text, and image data types will be removed in a future version of SQL Server. Avoid using these data types in new development work, and plan to modify applications that currently use them. Use nvarchar(max), varchar(max), and varbinary(max) instead.

        "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
        0
        • M4RZB4NiM M4RZB4Ni

          Hi
          I have saved a pic to my Sql Server Db
          but When i want To load it in my Graphic View
          DO nothing :|
          this is my code:
          .h file

                  QPixmap originalPixmap;
                  QPixmap outPixmap;
                  QByteArray inByteArraye;
                  QByteArray outByteArray;
          

          .cpp file

              readSkeletonPicQry.exec("SELECT SskeletonPic FROM Patient_File WHERE SmeliCode='"+seMcode+"'");
              outByteArray = readSkeletonPicQry.value(0).toByteArray();
              outPixmap = QPixmap();
              outPixmap.loadFromData(outByteArray,"PNG");
              scene->addPixmap(outPixmap);
              ui->graphicsView_2->setScene(scene)
          

          my datatype in sql server Table in IMAGE and its store pics Fine
          but i cant Show pic in graphic View From Table
          *My Table Pic
          whats Wrong?

          M4RZB4NiM Offline
          M4RZB4NiM Offline
          M4RZB4Ni
          wrote on last edited by M4RZB4Ni
          #16

          @M4RZB4Ni
          this is all of my codes:
          see it and if you can correct it
          .h file:

          QImage *pix;
                  QImage originalPixmap;
                  QPixmap outPixmap;
                  QPixmap pxp;
                  QGraphicsPixmapItem pixItem;
                  QByteArray inByteArraye;
                  QByteArray outByteArray;
          

          .cpp file:

          void Medical_Records::shootScreen()
          {
              QScreen *screen = QGuiApplication::primaryScreen();
              if (const QWindow *window = windowHandle())
                  screen = window->screen();
              if (!screen)
                  return;
          
            originalPixmap=ui->graphicsView_2->grab().toImage();
              updateGraphicView();
          
          }
          void Medical_Records::initalizeVarables()
          {
                   shootScreen();
                  QBuffer inBuffer( &inByteArraye );
                  inBuffer.open(QIODevice::WriteOnly);
                  originalPixmap.save(&inBuffer,"PNG");
          }
          
          
          void Medical_Records::readSkeletonPic()
          {
              moveToThread(readSkeletonPicThread);
            readSkeletonPicQry.exec("SELECT SskeletonPic FROM Patient_File WHERE SmeliCode='"+seMcode+"'");
              readSkeletonPicQry.next();
              outByteArray = readSkeletonPicQry.value(0).toByteArray();
              //outPixmap = QPixmap();
              originalPixmap.loadFromData(outByteArray,"PNG");
              qDebug() << "outByteArray :" << outByteArray.size();
              qDebug() << "outByteArray :" << originalPixmap.size();
              outPixmap.fromImage(originalPixmap.fromData(outByteArray,"PNG"));
              scene->addPixmap(outPixmap);
              ui->graphicsView_2->setScene(scene);
              qDebug() << readSkeletonPicQry.exec();
              readSkeletonPicThread->start();
          }
          

          Thanks
          M4RZB4Ni

          1 Reply Last reply
          0
          • VRoninV Offline
            VRoninV Offline
            VRonin
            wrote on last edited by
            #17

            i don't get the threading thing but it's probably not the point here. where did you get the
            "Cant Convert varchar datatype to VARBINARY(MAX)" error?

            "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

            M4RZB4NiM 1 Reply Last reply
            0
            • VRoninV VRonin

              i don't get the threading thing but it's probably not the point here. where did you get the
              "Cant Convert varchar datatype to VARBINARY(MAX)" error?

              M4RZB4NiM Offline
              M4RZB4NiM Offline
              M4RZB4Ni
              wrote on last edited by
              #18

              @VRonin
              when i want insert image into database after capture screenshot

              Thanks
              M4RZB4Ni

              1 Reply Last reply
              0
              • VRoninV Offline
                VRoninV Offline
                VRonin
                wrote on last edited by
                #19

                Can you post that code please?

                "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

                M4RZB4NiM 1 Reply Last reply
                0
                • VRoninV VRonin

                  Can you post that code please?

                  M4RZB4NiM Offline
                  M4RZB4NiM Offline
                  M4RZB4Ni
                  wrote on last edited by
                  #20

                  @VRonin
                  yes of course
                  thanks so much

                  this is code :

                  void Medical_Records::initalizeVarables()
                  {
                  
                          shootScreen();
                          QBuffer inBuffer( &inByteArraye );
                          inBuffer.open(QIODevice::WriteOnly);
                          originalPixmap.save(&inBuffer,"PNG");
                  }
                  void Medical_Records::submitWithScreenShot()
                  {
                  
                    initalizeVarables();
                      QSqlQuery sql;
                      sql.exec("UPDATE Patient_File SET SskeletonPic='"+inByteArraye+"' WHERE SmeliCode='"+seMcode+"';");
                  }
                  

                  Thanks
                  M4RZB4Ni

                  1 Reply Last reply
                  0
                  • VRoninV Offline
                    VRoninV Offline
                    VRonin
                    wrote on last edited by VRonin
                    #21

                    yep, you should check QSqlQuery::bindValue

                    sql.prepare("UPDATE Patient_File SET SskeletonPic= :skp  WHERE SmeliCode= :smc");
                    sql.bindValue(":skp",inByteArraye);
                    sql.bindValue(":smc",seMcode);
                    sql.exec();
                    

                    this also prevents SQL Injection. You should never really use unescaped input directly to build the query string

                    "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

                    M4RZB4NiM 1 Reply Last reply
                    1
                    • VRoninV VRonin

                      yep, you should check QSqlQuery::bindValue

                      sql.prepare("UPDATE Patient_File SET SskeletonPic= :skp  WHERE SmeliCode= :smc");
                      sql.bindValue(":skp",inByteArraye);
                      sql.bindValue(":smc",seMcode);
                      sql.exec();
                      

                      this also prevents SQL Injection. You should never really use unescaped input directly to build the query string

                      M4RZB4NiM Offline
                      M4RZB4NiM Offline
                      M4RZB4Ni
                      wrote on last edited by
                      #22

                      @VRonin
                      thanks but my problem is in Load image not save it!
                      Thank a lot My Friend :)

                      Thanks
                      M4RZB4Ni

                      1 Reply Last reply
                      0
                      • VRoninV Offline
                        VRoninV Offline
                        VRonin
                        wrote on last edited by VRonin
                        #23

                        make the field varbinary(max), save it that way and the code you have will work, no changes needed on the load part

                        image in SQL server is a fixed length string. it has nothing to do with images

                        "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
                        4
                        • KutyusK Offline
                          KutyusK Offline
                          Kutyus
                          wrote on last edited by
                          #24

                          Hi!
                          The same problem, you could solve?
                          Thanks

                          VRoninV 1 Reply Last reply
                          0
                          • KutyusK Kutyus

                            Hi!
                            The same problem, you could solve?
                            Thanks

                            VRoninV Offline
                            VRoninV Offline
                            VRonin
                            wrote on last edited by
                            #25

                            @Kutyus

                            Summary of the above:

                            • in the database use the type VABBINARY not IMAGE
                            • use QSqlQuery::bindValue instead of string concatenation to build your query

                            "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

                            KutyusK 1 Reply Last reply
                            3
                            • VRoninV VRonin

                              @Kutyus

                              Summary of the above:

                              • in the database use the type VABBINARY not IMAGE
                              • use QSqlQuery::bindValue instead of string concatenation to build your query
                              KutyusK Offline
                              KutyusK Offline
                              Kutyus
                              wrote on last edited by
                              #26

                              @VRonin Thank you for reply, but my problem is the load image from database, please see my another question:
                              QT 5.8 image from database error

                              1 Reply Last reply
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