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Declaration of function and use it

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  • jsulmJ jsulm

    @gauravsharma0190 Well, I guess you have many issues there...

    G Offline
    G Offline
    gauravsharma0190
    wrote on last edited by
    #59

    @jsulm
    Yeap.
    are they function's issuses or anything.
    I can't undersatnd everything is all right so Why all these issuses are there.
    I will send you these issue.

    G 1 Reply Last reply
    0
    • G gauravsharma0190

      @jsulm
      Yeap.
      are they function's issuses or anything.
      I can't undersatnd everything is all right so Why all these issuses are there.
      I will send you these issue.

      G Offline
      G Offline
      gauravsharma0190
      wrote on last edited by
      #60

      @gauravsharma0190
      Here are all the errors
      ...

      /home/pi/Desktop/qt/Desktop1/onTrackBall.cpp:9: error: 'blur' was not declared in this scope
           blur(gray, edge, Size(3,3));
                                     ^
      /home/pi/Desktop/qt/Desktop1/onTrackBall.cpp:6: error: 'Mat' does not name a type
       Mat image, gray, edge, cedge;
       ^
      /home/pi/Desktop/qt/Desktop1/onTrackBall.cpp:7: error: 'void CannyThreshold(int, void*)' was declared 'extern' and later 'static' [-fpermissive]
         static void CannyThreshold(int, void*)
                                              ^
      /home/pi/Desktop/qt/Desktop1/onTrackBall.cpp:-1: In function 'void CannyThreshold(int, void*)':
      
      /home/pi/Desktop/qt/Desktop1/onTrackBall.cpp:9: error: 'edge' was not declared in this scope
           blur(gray, edge, Size(3,3));
                      ^
      /home/pi/Desktop/qt/Desktop1/onTrackBall.cpp:9: error: 'edge' was not declared in this scope
           blur(gray, edge, Size(3,3));
                      ^
      /home/pi/Desktop/qt/Desktop1/onTrackBall.cpp:9: error: 'blur' was not declared in this scope
           blur(gray, edge, Size(3,3));
                                     ^
      
      /home/pi/Desktop/qt/Desktop1/onTrackBall.cpp:12: error: 'Canny' was not declared in this scope
           Canny(edge, edge, edgeThresh, edgeThresh*3, 3);
                                                        ^
      /home/pi/Desktop/qt/Desktop1/onTrackBall.cpp:13: error: 'cedge' was not declared in this scope
           cedge = Scalar::all(0);
           ^
      /home/pi/Desktop/qt/Desktop1/onTrackBall.cpp:15: error: 'src' was not declared in this scope
           src.copyTo(cedge, edge);
           ^
      /home/pi/Desktop/qt/Desktop1/onTrackBall.cpp:16: error: 'imshow' was not declared in this scope
           imshow("Edge map", cedge);
                                   ^
      /usr/local/include/opencv2/highgui/highgui.hpp:78: note:   'cv::imshow'
       CV_EXPORTS_W void imshow(const string& winname, InputArray mat);
      
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      • jsulmJ jsulm

        @gauravsharma0190 Well, I guess you have many issues there...

        G Offline
        G Offline
        gauravsharma0190
        wrote on last edited by
        #61
        This post is deleted!
        1 Reply Last reply
        0
        • jsulmJ jsulm

          @gauravsharma0190 Well, I guess you have many issues there...

          G Offline
          G Offline
          gauravsharma0190
          wrote on last edited by
          #62

          @jsulm
          Hey i have posted the error
          i can't undersatnd why i am getting these error.
          everything is all right.

          jsulmJ 1 Reply Last reply
          0
          • G gauravsharma0190

            @jsulm
            Hey i have posted the error
            i can't undersatnd why i am getting these error.
            everything is all right.

            jsulmJ Offline
            jsulmJ Offline
            jsulm
            Lifetime Qt Champion
            wrote on last edited by jsulm
            #63

            @gauravsharma0190 Nothing is all right with this code.
            "was not declared in this scope" - you have to check where are those declared or why they are not declared (blur, edge, Mat,...). For example:

            cedge = Scalar::all(0);
            

            where is cedge declared? You're trying to access a variable which was not declared.

            This one says that you first declared the function extern and later static. Why? Since it is just a function it neither has to be static nor extern!

            error: 'void CannyThreshold(int, void*)' was declared 'extern' and later 'static' [-fpermissive]
               static void CannyThreshold(int, void*)
            

            You really have to fix your code! And I really don't understand why you think your code is OK although there are really basic issues (not related to Qt at all)!

            https://forum.qt.io/topic/113070/qt-code-of-conduct

            G 1 Reply Last reply
            1
            • jsulmJ jsulm

              @gauravsharma0190 Nothing is all right with this code.
              "was not declared in this scope" - you have to check where are those declared or why they are not declared (blur, edge, Mat,...). For example:

              cedge = Scalar::all(0);
              

              where is cedge declared? You're trying to access a variable which was not declared.

              This one says that you first declared the function extern and later static. Why? Since it is just a function it neither has to be static nor extern!

              error: 'void CannyThreshold(int, void*)' was declared 'extern' and later 'static' [-fpermissive]
                 static void CannyThreshold(int, void*)
              

              You really have to fix your code! And I really don't understand why you think your code is OK although there are really basic issues (not related to Qt at all)!

              G Offline
              G Offline
              gauravsharma0190
              wrote on last edited by
              #64

              @jsulm
              i declare all these variable inside onTrach.cpp file.
              blur is function name which is in imgproc.hpp header.
              Canny is also function name which is declared in highgui.h header.

              jsulmJ 1 Reply Last reply
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              • G gauravsharma0190

                @jsulm
                i declare all these variable inside onTrach.cpp file.
                blur is function name which is in imgproc.hpp header.
                Canny is also function name which is declared in highgui.h header.

                jsulmJ Offline
                jsulmJ Offline
                jsulm
                Lifetime Qt Champion
                wrote on last edited by
                #65

                @gauravsharma0190
                Can you post onTrach.cpp and onTrach.h?

                https://forum.qt.io/topic/113070/qt-code-of-conduct

                G 1 Reply Last reply
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                • jsulmJ jsulm

                  @gauravsharma0190
                  Can you post onTrach.cpp and onTrach.h?

                  G Offline
                  G Offline
                  gauravsharma0190
                  wrote on last edited by gauravsharma0190
                  #66

                  @jsulm

                  #include"onTrack.h"
                  #include <opencv2/highgui/highgui.hpp>
                  #include <opencv2/core/core.hpp>
                  #include<opencv2/imgproc/imgproc.hpp>
                  int edgeThresh = 1;
                  //Mat image,gray,edge,cedge; 
                  
                    void CannyThreshold(int, void*)
                  {
                  Mat image, gray, edge, cedge;
                      blur(gray, edge, Size(3,3));
                  
                      // Run the edge detector on grayscale
                      Canny(edge, edge, edgeThresh, edgeThresh*3, 3);
                      cedge = Scalar::all(0);
                  
                      src.copyTo(cedge, edge);
                      imshow("Edge map", cedge);
                  }
                  
                  

                  .H file

                  #define ONTRACKBALL_H_
                    int CannyThreshold(int,void* );
                  #endif
                  //your code here
                  

                  Mat is opencv function which is declare in highgui.h
                  header.
                  all these functions are present in header which i added in code.

                  jsulmJ 2 Replies Last reply
                  0
                  • G gauravsharma0190

                    @jsulm

                    #include"onTrack.h"
                    #include <opencv2/highgui/highgui.hpp>
                    #include <opencv2/core/core.hpp>
                    #include<opencv2/imgproc/imgproc.hpp>
                    int edgeThresh = 1;
                    //Mat image,gray,edge,cedge; 
                    
                      void CannyThreshold(int, void*)
                    {
                    Mat image, gray, edge, cedge;
                        blur(gray, edge, Size(3,3));
                    
                        // Run the edge detector on grayscale
                        Canny(edge, edge, edgeThresh, edgeThresh*3, 3);
                        cedge = Scalar::all(0);
                    
                        src.copyTo(cedge, edge);
                        imshow("Edge map", cedge);
                    }
                    
                    

                    .H file

                    #define ONTRACKBALL_H_
                      int CannyThreshold(int,void* );
                    #endif
                    //your code here
                    

                    Mat is opencv function which is declare in highgui.h
                    header.
                    all these functions are present in header which i added in code.

                    jsulmJ Offline
                    jsulmJ Offline
                    jsulm
                    Lifetime Qt Champion
                    wrote on last edited by
                    #67

                    @gauravsharma0190 What is Mat and where is it declared?

                    https://forum.qt.io/topic/113070/qt-code-of-conduct

                    1 Reply Last reply
                    0
                    • G gauravsharma0190

                      @jsulm

                      #include"onTrack.h"
                      #include <opencv2/highgui/highgui.hpp>
                      #include <opencv2/core/core.hpp>
                      #include<opencv2/imgproc/imgproc.hpp>
                      int edgeThresh = 1;
                      //Mat image,gray,edge,cedge; 
                      
                        void CannyThreshold(int, void*)
                      {
                      Mat image, gray, edge, cedge;
                          blur(gray, edge, Size(3,3));
                      
                          // Run the edge detector on grayscale
                          Canny(edge, edge, edgeThresh, edgeThresh*3, 3);
                          cedge = Scalar::all(0);
                      
                          src.copyTo(cedge, edge);
                          imshow("Edge map", cedge);
                      }
                      
                      

                      .H file

                      #define ONTRACKBALL_H_
                        int CannyThreshold(int,void* );
                      #endif
                      //your code here
                      

                      Mat is opencv function which is declare in highgui.h
                      header.
                      all these functions are present in header which i added in code.

                      jsulmJ Offline
                      jsulmJ Offline
                      jsulm
                      Lifetime Qt Champion
                      wrote on last edited by
                      #68

                      @gauravsharma0190 Didn't you forget

                      using namespace cv;
                      

                      in the cpp file?

                      https://forum.qt.io/topic/113070/qt-code-of-conduct

                      G 1 Reply Last reply
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                      • jsulmJ jsulm

                        @gauravsharma0190 Didn't you forget

                        using namespace cv;
                        

                        in the cpp file?

                        G Offline
                        G Offline
                        gauravsharma0190
                        wrote on last edited by
                        #69

                        @jsulm
                        Mat is basically a class with two data parts: the matrix header (containing information such as the size of the matrix, the method used for storing, at which address is the matrix stored, and so on) and a pointer to the matrix containing the pixel values (taking any dimensionality depending on the method chosen for storing) . The matrix header size is constant, however the size of the matrix itself may vary from image to image and usually is larger by orders of magnitude

                        G 1 Reply Last reply
                        0
                        • G gauravsharma0190

                          @jsulm
                          Mat is basically a class with two data parts: the matrix header (containing information such as the size of the matrix, the method used for storing, at which address is the matrix stored, and so on) and a pointer to the matrix containing the pixel values (taking any dimensionality depending on the method chosen for storing) . The matrix header size is constant, however the size of the matrix itself may vary from image to image and usually is larger by orders of magnitude

                          G Offline
                          G Offline
                          gauravsharma0190
                          wrote on last edited by
                          #70

                          @gauravsharma0190
                          Hey jslum
                          thanks very mush i did it without error
                          Now new problem arises when i clicked the push button it tells
                          The program has unexpectedly finished.
                          /home/pi/Desktop/qt /build-Desktop1-GCC Local/Desktop crashed.

                          jsulmJ 1 Reply Last reply
                          0
                          • G gauravsharma0190

                            @gauravsharma0190
                            Hey jslum
                            thanks very mush i did it without error
                            Now new problem arises when i clicked the push button it tells
                            The program has unexpectedly finished.
                            /home/pi/Desktop/qt /build-Desktop1-GCC Local/Desktop crashed.

                            jsulmJ Offline
                            jsulmJ Offline
                            jsulm
                            Lifetime Qt Champion
                            wrote on last edited by
                            #71

                            @gauravsharma0190 Most probably it crashes because of an invalid pointer. Debug your application step by step to see where exactly it crashes.

                            https://forum.qt.io/topic/113070/qt-code-of-conduct

                            G 1 Reply Last reply
                            0
                            • jsulmJ jsulm

                              @gauravsharma0190 Most probably it crashes because of an invalid pointer. Debug your application step by step to see where exactly it crashes.

                              G Offline
                              G Offline
                              gauravsharma0190
                              wrote on last edited by
                              #72

                              @jsulm
                              Hello sir
                              i debug the programme but when i press button it tells
                              the inferior stooped because it receives signal from OS
                              Signal name SIGABRT
                              Signal mean Aborted.
                              Now how to solve it

                              jsulmJ 1 Reply Last reply
                              0
                              • G gauravsharma0190

                                @jsulm
                                Hello sir
                                i debug the programme but when i press button it tells
                                the inferior stooped because it receives signal from OS
                                Signal name SIGABRT
                                Signal mean Aborted.
                                Now how to solve it

                                jsulmJ Offline
                                jsulmJ Offline
                                jsulm
                                Lifetime Qt Champion
                                wrote on last edited by jsulm
                                #73

                                @gauravsharma0190 Put a breakpoint in the slot which is called when you press the button and check where exactly it crashes.

                                https://forum.qt.io/topic/113070/qt-code-of-conduct

                                G 1 Reply Last reply
                                1
                                • G Offline
                                  G Offline
                                  gauravsharma0190
                                  wrote on last edited by gauravsharma0190
                                  #74

                                  IT CRASHES WHERE FUNCTION ontrack()
                                  defination
                                  Canny(edge, edge, edgeThresh, edgeThresh*3, 3);
                                  kernel_size issue i think.
                                  int kernel_size =3;
                                  here

                                  1 Reply Last reply
                                  0
                                  • jsulmJ jsulm

                                    @gauravsharma0190 Put a breakpoint in the slot which is called when you press the button and check where exactly it crashes.

                                    G Offline
                                    G Offline
                                    gauravsharma0190
                                    wrote on last edited by
                                    #75

                                    @jsulm
                                    It crashes when i press the push button .
                                    I debugged it and found it creshes when my function call.
                                    Error found->it takes signal from OS.
                                    Now How to fix it.

                                    jsulmJ 2 Replies Last reply
                                    0
                                    • G gauravsharma0190

                                      @jsulm
                                      It crashes when i press the push button .
                                      I debugged it and found it creshes when my function call.
                                      Error found->it takes signal from OS.
                                      Now How to fix it.

                                      jsulmJ Offline
                                      jsulmJ Offline
                                      jsulm
                                      Lifetime Qt Champion
                                      wrote on last edited by
                                      #76

                                      @gauravsharma0190 How to fix what?
                                      What do you mean by "Error found->it takes signal from OS" - what OS signal do you mean? Do you mean SIGABRT?
                                      I don't know how to fix it because I have no idea what the problem is. But usually such problems are caused by bugs in applications. You have to check your code and see what is wrong at the line where your application crashes.

                                      https://forum.qt.io/topic/113070/qt-code-of-conduct

                                      1 Reply Last reply
                                      0
                                      • G gauravsharma0190

                                        @jsulm
                                        It crashes when i press the push button .
                                        I debugged it and found it creshes when my function call.
                                        Error found->it takes signal from OS.
                                        Now How to fix it.

                                        jsulmJ Offline
                                        jsulmJ Offline
                                        jsulm
                                        Lifetime Qt Champion
                                        wrote on last edited by
                                        #77

                                        @gauravsharma0190 Can you post the code and mark the line where it crashes?

                                        https://forum.qt.io/topic/113070/qt-code-of-conduct

                                        G 1 Reply Last reply
                                        0
                                        • jsulmJ jsulm

                                          @gauravsharma0190 Can you post the code and mark the line where it crashes?

                                          G Offline
                                          G Offline
                                          gauravsharma0190
                                          wrote on last edited by gauravsharma0190
                                          #78

                                          @jsulm
                                          Mainwindow.cpp

                                          void MainWindow::on_onTrackball_clicked()
                                          {
                                              int threshold_value = 0;
                                              int threshold_type = 3;
                                              int const max_value = 255;
                                              int const max_type = 4;
                                             // int const max_BINARY_value = 255;
                                          
                                              Mat src, src_gray, dst;
                                            //  char* window_name = "Threshold Demo";
                                          
                                              //char* trackbar_type = "Type: \n 0: Binary \n 1: Binary Inverted \n 2: Truncate \n 3: To Zero \n 4: To Zero Inverted";
                                              //char* trackbar_value = "Value";
                                          
                                          
                                          
                                          
                                              /// Load image
                                              src = imread( "/home/pi/Desktop/b4.jpg");
                                          
                                          
                                                /// Convert the image to Gray
                                                cvtColor( src, src_gray, CV_BGR2GRAY );
                                          
                                                /// Create a window to display results
                                                namedWindow( "Threshold", CV_WINDOW_AUTOSIZE );
                                          
                                                /// Create Trackbar to choose type of Threshold
                                                createTrackbar( "Type: \n 0: Binary \n 1: Binary Inverted \n 2: Truncate \n 3: To Zero \n 4: To Zero Inverted","Threshold", &threshold_type, max_type, Threshold_Demo );
                                          
                                                createTrackbar( "value","Threshold", &threshold_value, max_value, Threshold_Demo );
                                          
                                                /// Call the function to initialize
                                          @@@   ***Threshold_Demo( 0, 0)***
                                          
                                          
                                          }
                                          

                                          onTrack.h

                                          #ifndef ONTRACKBALL_H_
                                          #define ONTRACKBALL_H_
                                            void Threshold_Demo( int, void* );
                                          #endif
                                          

                                          ontrack.cpp

                                          void Threshold_Demo( int, void* )
                                          {
                                            /* 0: Binary
                                               1: Binary Inverted
                                               2: Threshold Truncated
                                               3: Threshold to Zero
                                               4: Threshold to Zero Inverted
                                             */
                                          
                                          @@threshold( src_gray, dst, threshold_value, max_BINARY_value,threshold_type );
                                          
                                            imshow("Threshold", dst );
                                          

                                          Here @---> Error

                                          jsulmJ 1 Reply Last reply
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