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Declaration of function and use it

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  • G gauravsharma0190
    18 Jul 2016, 11:55

    @mrjj
    it is defined as

    ///ontrack.h///
    
    #ifndef __ONTRACK_h
    #define __ONTRACK_h
    void cannyThresold(int,void*);
    #endif
    ......
    
    ///ontrack.cpp
    #include "ontrack.h"
    #include<opencv2/opencv.hpp>
    #include <opencv2/highgui/highgui.hpp>
    #include <opencv2/core/core.hpp>
    void CannyThreshold(int, void*)
    {
    /// Reduce noise with a kernel 3x3
    blur( src_gray, detected_edges, Size(3,3) );
    /// Canny detector
    Canny( detected_edges, detected_edges, lowThreshold, lowThreshold*ratio, kernel_size );
    
    /// Using Canny's output as a mask, we display our result
    dst = Scalar::all(0);
    
    src.copyTo( dst, detected_edges);
    imshow( window_name, dst );
    }
    

    .....
    thus i include ontrack.h in mainwindow.cpp code.
    but error occurs.
    Why??
    i can't understand.

    J Offline
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    jsulm
    Lifetime Qt Champion
    wrote on 18 Jul 2016, 12:32 last edited by
    #46

    @gauravsharma0190 You call it like this CannyThreshold(0, 0); and in ontrack.cpp it is defined like void CannyThreshold(int, void*). But in ontrack.h it is void cannyThresold(int,void*); please fix the name of the function.

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

    M G 2 Replies Last reply 18 Jul 2016, 12:37
    1
    • J jsulm
      18 Jul 2016, 12:32

      @gauravsharma0190 You call it like this CannyThreshold(0, 0); and in ontrack.cpp it is defined like void CannyThreshold(int, void*). But in ontrack.h it is void cannyThresold(int,void*); please fix the name of the function.

      M Offline
      M Offline
      mrjj
      Lifetime Qt Champion
      wrote on 18 Jul 2016, 12:37 last edited by
      #47

      @jsulm
      heh Good spotted. completely missed "old" :)

      G 1 Reply Last reply 19 Jul 2016, 05:48
      1
      • M mrjj
        18 Jul 2016, 12:37

        @jsulm
        heh Good spotted. completely missed "old" :)

        G Offline
        G Offline
        gauravsharma0190
        wrote on 19 Jul 2016, 05:48 last edited by
        #48

        @mrjj
        I fix canny as Canny in .h file
        but again error occurs.

        1 Reply Last reply
        0
        • J jsulm
          18 Jul 2016, 12:32

          @gauravsharma0190 You call it like this CannyThreshold(0, 0); and in ontrack.cpp it is defined like void CannyThreshold(int, void*). But in ontrack.h it is void cannyThresold(int,void*); please fix the name of the function.

          G Offline
          G Offline
          gauravsharma0190
          wrote on 19 Jul 2016, 06:17 last edited by
          #49

          @jsulm
          Hey i fixed it .But again error.

          J 1 Reply Last reply 19 Jul 2016, 06:22
          0
          • G gauravsharma0190
            19 Jul 2016, 06:17

            @jsulm
            Hey i fixed it .But again error.

            J Offline
            J Offline
            jsulm
            Lifetime Qt Champion
            wrote on 19 Jul 2016, 06:22 last edited by
            #50

            @gauravsharma0190 "But again error" - why don't you say what error you get now?

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

            G 1 Reply Last reply 19 Jul 2016, 06:25
            2
            • J jsulm
              19 Jul 2016, 06:22

              @gauravsharma0190 "But again error" - why don't you say what error you get now?

              G Offline
              G Offline
              gauravsharma0190
              wrote on 19 Jul 2016, 06:25 last edited by
              #51

              @jsulm
              yes it tells undefined reference to 'CannyThresold(int,void*)'.
              collect2:error ld returned 1 exit status.

              J 1 Reply Last reply 19 Jul 2016, 06:28
              0
              • G gauravsharma0190
                19 Jul 2016, 06:25

                @jsulm
                yes it tells undefined reference to 'CannyThresold(int,void*)'.
                collect2:error ld returned 1 exit status.

                J Offline
                J Offline
                jsulm
                Lifetime Qt Champion
                wrote on 19 Jul 2016, 06:28 last edited by
                #52

                @gauravsharma0190 Is ontrack.cpp part of your project and is it built?
                "undefined reference to 'CannyThresold(int,void*)" - means linker cannot find CannyThresold(int,void*)

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

                G 1 Reply Last reply 19 Jul 2016, 06:32
                1
                • J jsulm
                  19 Jul 2016, 06:28

                  @gauravsharma0190 Is ontrack.cpp part of your project and is it built?
                  "undefined reference to 'CannyThresold(int,void*)" - means linker cannot find CannyThresold(int,void*)

                  G Offline
                  G Offline
                  gauravsharma0190
                  wrote on 19 Jul 2016, 06:32 last edited by
                  #53

                  @jsulm
                  Actually i put .h and .cpp file in my qt project folder.

                  J 1 Reply Last reply 19 Jul 2016, 06:34
                  0
                  • G gauravsharma0190
                    19 Jul 2016, 06:32

                    @jsulm
                    Actually i put .h and .cpp file in my qt project folder.

                    J Offline
                    J Offline
                    jsulm
                    Lifetime Qt Champion
                    wrote on 19 Jul 2016, 06:34 last edited by
                    #54

                    @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
                    

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

                    G 1 Reply Last reply 19 Jul 2016, 06:39
                    1
                    • J jsulm
                      19 Jul 2016, 06:34

                      @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 19 Jul 2016, 06:39 last edited by
                      #55

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

                      J 1 Reply Last reply 19 Jul 2016, 06:41
                      0
                      • G gauravsharma0190
                        19 Jul 2016, 06:39

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

                        J Offline
                        J Offline
                        jsulm
                        Lifetime Qt Champion
                        wrote on 19 Jul 2016, 06:41 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 19 Jul 2016, 06:44
                        0
                        • J jsulm
                          19 Jul 2016, 06:41

                          @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 19 Jul 2016, 06:44 last edited by
                          #57

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

                          J 1 Reply Last reply 19 Jul 2016, 06:46
                          0
                          • G gauravsharma0190
                            19 Jul 2016, 06:44

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

                            J Offline
                            J Offline
                            jsulm
                            Lifetime Qt Champion
                            wrote on 19 Jul 2016, 06:46 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 19 Jul 2016, 07:09
                            0
                            • J jsulm
                              19 Jul 2016, 06:46

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

                              G Offline
                              G Offline
                              gauravsharma0190
                              wrote on 19 Jul 2016, 07:09 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 19 Jul 2016, 09:03
                              0
                              • G gauravsharma0190
                                19 Jul 2016, 07:09

                                @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 19 Jul 2016, 09:03 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
                                0
                                • J jsulm
                                  19 Jul 2016, 06:46

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

                                  G Offline
                                  G Offline
                                  gauravsharma0190
                                  wrote on 19 Jul 2016, 09:15 last edited by
                                  #61
                                  This post is deleted!
                                  1 Reply Last reply
                                  0
                                  • J jsulm
                                    19 Jul 2016, 06:46

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

                                    G Offline
                                    G Offline
                                    gauravsharma0190
                                    wrote on 19 Jul 2016, 09:31 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.

                                    J 1 Reply Last reply 19 Jul 2016, 10:01
                                    0
                                    • G gauravsharma0190
                                      19 Jul 2016, 09:31

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

                                      J Offline
                                      J Offline
                                      jsulm
                                      Lifetime Qt Champion
                                      wrote on 19 Jul 2016, 10:01 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 19 Jul 2016, 10:33
                                      1
                                      • J jsulm
                                        19 Jul 2016, 10:01

                                        @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 19 Jul 2016, 10:33 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.

                                        J 1 Reply Last reply 19 Jul 2016, 10:34
                                        0
                                        • G gauravsharma0190
                                          19 Jul 2016, 10:33

                                          @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.

                                          J Offline
                                          J Offline
                                          jsulm
                                          Lifetime Qt Champion
                                          wrote on 19 Jul 2016, 10:34 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 19 Jul 2016, 10:41
                                          0

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