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Qt Cross Compile Library Path for Raspberry pi 3

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  • Q Offline
    Q Offline
    qtross
    wrote on 29 Jul 2019, 06:05 last edited by qtross
    #1

    Hi,
    I followed instructions in this website for cross compile link and I am able to build succesfully to my Raspberry pi target machine. However, I would like to cross compile with opencv, wiring pi and, raspicam c++ libraries. Before cross compile I already installed these libraries on raspberry pi, to understand cross compiling procedure with libraries I just tried and build an app with opencv library and I could not make it work. While setuping cross compile, I can reach the needed libraries in sysroot folder(raspi/sysroot/usr/include/opencv or opencv2) which were transferred from raspberry pi to my local machine. in .pro file I showed this folder path as in the picture:

    INCLUDEPATH += /home/nehir-arda/raspi/sysroot/usr/include/opencv
    INCLUDEPATH += /home/nehir-arda/raspi/sysroot/usr/include/opencv2
    #LIBS += -L/usr/local/lib -lopencv_core -lopencv_highgui -lopencv_imgproc -lopencv_videoio -lopencv_imgcodecs -lopencv_features2d
    LIBS += -L/home/nehir-arda/raspi/sysroot/usr/lib/arm-linux-gnueabihf -lopencv_core -lopencv_highgui -lopencv_imgproc -lopencv_videoio -lopencv_imgcodecs -lopencv_features2d

    But, when I try to build it gives my error which says cannot find opencv libraries. What might be the problem?

    Thank you for any suggestions.

    J 1 Reply Last reply 29 Jul 2019, 06:10
    0
    • Q qtross
      29 Jul 2019, 06:05

      Hi,
      I followed instructions in this website for cross compile link and I am able to build succesfully to my Raspberry pi target machine. However, I would like to cross compile with opencv, wiring pi and, raspicam c++ libraries. Before cross compile I already installed these libraries on raspberry pi, to understand cross compiling procedure with libraries I just tried and build an app with opencv library and I could not make it work. While setuping cross compile, I can reach the needed libraries in sysroot folder(raspi/sysroot/usr/include/opencv or opencv2) which were transferred from raspberry pi to my local machine. in .pro file I showed this folder path as in the picture:

      INCLUDEPATH += /home/nehir-arda/raspi/sysroot/usr/include/opencv
      INCLUDEPATH += /home/nehir-arda/raspi/sysroot/usr/include/opencv2
      #LIBS += -L/usr/local/lib -lopencv_core -lopencv_highgui -lopencv_imgproc -lopencv_videoio -lopencv_imgcodecs -lopencv_features2d
      LIBS += -L/home/nehir-arda/raspi/sysroot/usr/lib/arm-linux-gnueabihf -lopencv_core -lopencv_highgui -lopencv_imgproc -lopencv_videoio -lopencv_imgcodecs -lopencv_features2d

      But, when I try to build it gives my error which says cannot find opencv libraries. What might be the problem?

      Thank you for any suggestions.

      J Offline
      J Offline
      jsulm
      Lifetime Qt Champion
      wrote on 29 Jul 2019, 06:10 last edited by
      #2

      @qtross Libs are usually NOT inside include directories! It should be /home/.../usr/lib

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

      1 Reply Last reply
      2
      • Q Offline
        Q Offline
        qtross
        wrote on 29 Jul 2019, 06:33 last edited by qtross
        #3

        @jsulm Thanks for the reply, I changed the path and, I have now this warning;

        0_1564382180216_screen2.png

        Before cross compile, I already had opencv installed on my local machine and I still have. Though, missing file exists in sysroot/usr/lib folder, do you think that having another opencv library on local machine cause that warning? Because, after cross compile, I did not symmlink transferred libraries on my local machine.
        Thanks

        J 1 Reply Last reply 29 Jul 2019, 06:46
        0
        • Q qtross
          29 Jul 2019, 06:33

          @jsulm Thanks for the reply, I changed the path and, I have now this warning;

          0_1564382180216_screen2.png

          Before cross compile, I already had opencv installed on my local machine and I still have. Though, missing file exists in sysroot/usr/lib folder, do you think that having another opencv library on local machine cause that warning? Because, after cross compile, I did not symmlink transferred libraries on my local machine.
          Thanks

          J Offline
          J Offline
          jsulm
          Lifetime Qt Champion
          wrote on 29 Jul 2019, 06:46 last edited by jsulm
          #4

          @qtross Please do not post screen-shots, post text!
          How did you configure your Kit? You should set the sysroot.

          "Before cross compile, I already had opencv installed on my local machine and I still have. Though, missing file exists in sysroot/usr/lib folder, do you think that having another opencv library on local machine cause that warning?" - this is not how cross compiling works. It doesn't matter what you installed on your host machine. What matters is what is in your sysroot.

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

          Q 1 Reply Last reply 29 Jul 2019, 06:58
          1
          • J jsulm
            29 Jul 2019, 06:46

            @qtross Please do not post screen-shots, post text!
            How did you configure your Kit? You should set the sysroot.

            "Before cross compile, I already had opencv installed on my local machine and I still have. Though, missing file exists in sysroot/usr/lib folder, do you think that having another opencv library on local machine cause that warning?" - this is not how cross compiling works. It doesn't matter what you installed on your host machine. What matters is what is in your sysroot.

            Q Offline
            Q Offline
            qtross
            wrote on 29 Jul 2019, 06:58 last edited by qtross
            #5

            @jsulm said in Qt Cross Compile Library Path for Raspberry pi 3:

            /home/nehir-arda/raspi/tools/arm-bcm2708/gcc-linaro-arm-linux-gnueabihf-raspbian-x64/bin/../lib/gcc/arm-linux-gnueabihf/4.8.3/../../../../arm-linux-gnueabihf/bin/ld: warning: libblas.so.3, needed by /home/nehir-arda/raspi/sysroot/usr/lib/libarmadillo.so.9, not found (try using -rpath or -rpath-link)
            /home/nehir-arda/raspi/tools/arm-bcm2708/gcc-linaro-arm-linux-gnueabihf-raspbian-x64/bin/../lib/gcc/arm-linux-gnueabihf/4.8.3/../../../../arm-linux-gnueabihf/bin/ld: warning: liblapack.so.3, needed by /home/nehir-arda/raspi/sysroot/usr/lib/libarmadillo.so.9, not found (try using -rpath or -rpath-link)

            Sorry about it, this is text version of my warning. My local machine name is :nehir-arda. I showed as local in first picture, but I corrected while I was building.

            It says libarmadillo.so.9 and libblass.so.3 are missing but I can find them in the same folder that gives error.

            And my sysroot path :

            /home/nehir-arda/raspi/sysroot

            J 1 Reply Last reply 29 Jul 2019, 07:07
            0
            • Q qtross
              29 Jul 2019, 06:58

              @jsulm said in Qt Cross Compile Library Path for Raspberry pi 3:

              /home/nehir-arda/raspi/tools/arm-bcm2708/gcc-linaro-arm-linux-gnueabihf-raspbian-x64/bin/../lib/gcc/arm-linux-gnueabihf/4.8.3/../../../../arm-linux-gnueabihf/bin/ld: warning: libblas.so.3, needed by /home/nehir-arda/raspi/sysroot/usr/lib/libarmadillo.so.9, not found (try using -rpath or -rpath-link)
              /home/nehir-arda/raspi/tools/arm-bcm2708/gcc-linaro-arm-linux-gnueabihf-raspbian-x64/bin/../lib/gcc/arm-linux-gnueabihf/4.8.3/../../../../arm-linux-gnueabihf/bin/ld: warning: liblapack.so.3, needed by /home/nehir-arda/raspi/sysroot/usr/lib/libarmadillo.so.9, not found (try using -rpath or -rpath-link)

              Sorry about it, this is text version of my warning. My local machine name is :nehir-arda. I showed as local in first picture, but I corrected while I was building.

              It says libarmadillo.so.9 and libblass.so.3 are missing but I can find them in the same folder that gives error.

              And my sysroot path :

              /home/nehir-arda/raspi/sysroot

              J Offline
              J Offline
              jsulm
              Lifetime Qt Champion
              wrote on 29 Jul 2019, 07:07 last edited by
              #6

              @qtross said in Qt Cross Compile Library Path for Raspberry pi 3:

              It says libarmadillo.so.9 and libblass.so.3 are missing but I can find them in the same folder that gives error.

              In your sysroot?

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

              Q 1 Reply Last reply 29 Jul 2019, 07:12
              0
              • J jsulm
                29 Jul 2019, 07:07

                @qtross said in Qt Cross Compile Library Path for Raspberry pi 3:

                It says libarmadillo.so.9 and libblass.so.3 are missing but I can find them in the same folder that gives error.

                In your sysroot?

                Q Offline
                Q Offline
                qtross
                wrote on 29 Jul 2019, 07:12 last edited by
                #7

                @jsulm

                Yes I can find libarmadillo.so.9 and libblass.so.3 in this folder

                /home/nehir-arda/raspi/sysroot/usr/lib

                J 1 Reply Last reply 29 Jul 2019, 07:14
                0
                • Q qtross
                  29 Jul 2019, 07:12

                  @jsulm

                  Yes I can find libarmadillo.so.9 and libblass.so.3 in this folder

                  /home/nehir-arda/raspi/sysroot/usr/lib

                  J Offline
                  J Offline
                  jsulm
                  Lifetime Qt Champion
                  wrote on 29 Jul 2019, 07:14 last edited by
                  #8

                  @qtross libblas.so.3 and liblapack.so.3 are not found actually, so are those two in your sysroot?

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

                  Q 1 Reply Last reply 29 Jul 2019, 07:21
                  0
                  • J jsulm
                    29 Jul 2019, 07:14

                    @qtross libblas.so.3 and liblapack.so.3 are not found actually, so are those two in your sysroot?

                    Q Offline
                    Q Offline
                    qtross
                    wrote on 29 Jul 2019, 07:21 last edited by
                    #9

                    @jsulm Yes i can find them but their folder is different:

                    /home/nehir-arda/raspi/sysroot/usr/lib/arm-linux-gnueabihf

                    I changed the path with the one above and could not build again.

                    J 1 Reply Last reply 29 Jul 2019, 07:27
                    0
                    • Q qtross
                      29 Jul 2019, 07:21

                      @jsulm Yes i can find them but their folder is different:

                      /home/nehir-arda/raspi/sysroot/usr/lib/arm-linux-gnueabihf

                      I changed the path with the one above and could not build again.

                      J Offline
                      J Offline
                      jsulm
                      Lifetime Qt Champion
                      wrote on 29 Jul 2019, 07:27 last edited by
                      #10

                      @qtross How did you create the sysroot?

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

                      Q 1 Reply Last reply 29 Jul 2019, 07:32
                      0
                      • J jsulm
                        29 Jul 2019, 07:27

                        @qtross How did you create the sysroot?

                        Q Offline
                        Q Offline
                        qtross
                        wrote on 29 Jul 2019, 07:32 last edited by qtross
                        #11

                        @jsulm I created with these commands:

                        mkdir sysroot sysroot/usr sysroot/opt
                        rsync -avz pi@raspberrypi.local:/lib sysroot
                        rsync -avz pi@raspberrypi.local:/usr/include sysroot/usr
                        rsync -avz pi@raspberrypi.local:/usr/lib sysroot/usr
                        rsync -avz pi@raspberrypi.local:/opt/vc sysroot/opt

                        I changed raspberrypi.local with my raspberry pi adress.

                        And symlink with these commands:

                        wget https://raw.githubusercontent.com/Kukkimonsuta/rpi-buildqt/master/scripts/utils/sysroot-relativelinks.py
                        chmod +x sysroot-relativelinks.py
                        ./sysroot-relativelinks.py sysroot

                        H 1 Reply Last reply 4 Dec 2019, 06:46
                        0
                        • Q qtross
                          29 Jul 2019, 07:32

                          @jsulm I created with these commands:

                          mkdir sysroot sysroot/usr sysroot/opt
                          rsync -avz pi@raspberrypi.local:/lib sysroot
                          rsync -avz pi@raspberrypi.local:/usr/include sysroot/usr
                          rsync -avz pi@raspberrypi.local:/usr/lib sysroot/usr
                          rsync -avz pi@raspberrypi.local:/opt/vc sysroot/opt

                          I changed raspberrypi.local with my raspberry pi adress.

                          And symlink with these commands:

                          wget https://raw.githubusercontent.com/Kukkimonsuta/rpi-buildqt/master/scripts/utils/sysroot-relativelinks.py
                          chmod +x sysroot-relativelinks.py
                          ./sysroot-relativelinks.py sysroot

                          H Offline
                          H Offline
                          Huy hust
                          wrote on 4 Dec 2019, 06:46 last edited by
                          #12

                          @qtross dear, i am facing the same error. Have you resolved it?

                          F 1 Reply Last reply 11 May 2021, 12:56
                          0
                          • H Huy hust
                            4 Dec 2019, 06:46

                            @qtross dear, i am facing the same error. Have you resolved it?

                            F Offline
                            F Offline
                            Fawkees
                            wrote on 11 May 2021, 12:56 last edited by
                            #13

                            @Huy-hust
                            Hi, I'm confronted with the same problem right now. Have you found a solution?

                            Pablo J. RoginaP 1 Reply Last reply 11 May 2021, 13:13
                            0
                            • F Fawkees
                              11 May 2021, 12:56

                              @Huy-hust
                              Hi, I'm confronted with the same problem right now. Have you found a solution?

                              Pablo J. RoginaP Offline
                              Pablo J. RoginaP Offline
                              Pablo J. Rogina
                              wrote on 11 May 2021, 13:13 last edited by
                              #14

                              @Fawkees said in Qt Cross Compile Library Path for Raspberry pi 3:

                              I'm confronted with the same problem right now

                              this post seems a little old, could it be possible you create a new one of your own, explaining what you've done so far and what issues you're facing? thanks.

                              Upvote the answer(s) that helped you solve the issue
                              Use "Topic Tools" button to mark your post as Solved
                              Add screenshots via postimage.org
                              Don't ask support requests via chat/PM. Please use the forum so others can benefit from the solution in the future

                              1 Reply Last reply
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