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Declaration of function and use it

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  • jsulmJ jsulm

    @gauravsharma0190 But did you add them to your project?
    They should be in the PRO file, like:

    SOURCES += main.cpp\
            mainwindow.cpp\
            ontrack.cpp
    
    HEADERS  += mainwindow.h\
            ontrack.h
    
    G Offline
    G Offline
    gauravsharma0190
    wrote on last edited by
    #55

    @jsulm
    i added it but gives error as
    parse error onTrack.cpp
    Makefile error 3

    jsulmJ 1 Reply Last reply
    0
    • G gauravsharma0190

      @jsulm
      i added it but gives error as
      parse error onTrack.cpp
      Makefile error 3

      jsulmJ Offline
      jsulmJ Offline
      jsulm
      Lifetime Qt Champion
      wrote on last edited by
      #56

      @gauravsharma0190 After changing PRO file you need to rerun qmake (right-click on the project in QtCreator and then "Run qmake". Then do a rebuild.

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

      G 1 Reply Last reply
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      • jsulmJ jsulm

        @gauravsharma0190 After changing PRO file you need to rerun qmake (right-click on the project in QtCreator and then "Run qmake". Then do a rebuild.

        G Offline
        G Offline
        gauravsharma0190
        wrote on last edited by
        #57

        @jsulm
        I done it
        Now gives many error regarding onTrack.cpp file.

        jsulmJ 1 Reply Last reply
        0
        • G gauravsharma0190

          @jsulm
          I done it
          Now gives many error regarding onTrack.cpp file.

          jsulmJ Offline
          jsulmJ Offline
          jsulm
          Lifetime Qt Champion
          wrote on last edited by
          #58

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

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

          G 3 Replies Last reply
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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
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            • 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);
              
              1 Reply Last reply
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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
                      0
                      • 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

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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
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                                    • 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
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