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PyQt QImage cna't copy, crash without error code

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  • D darrenleeleelee1

    @JonB Sorry I am not really get what did you mean.And I think I don't have any threading.(I think..)

    JonBJ Offline
    JonBJ Offline
    JonB
    wrote on last edited by JonB
    #18

    @darrenleeleelee1
    I have no idea what is behind your

            ds = dcmread('./5F329172_20170623_CR_2_1_1')
            arr = ds.pixel_array
    

    It's some external library stuff. (And btw I have no idea whether arr.shape[1], arr.shape[0] is the right thing to use. Don't bother to explain, just make sure it's correct for whatever this ds stuff is.)

    Try this:

    import copy
    ...
            arr = copy.copy(ds.pixel_array)
    # or even:
    #        arr = copy.deepcopy(ds.pixel_array)
    

    before you proceed to qimage = QtGui.QImage(arr, ...). Any better, crash-wise?

    D 1 Reply Last reply
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    • JonBJ JonB

      @darrenleeleelee1
      I have no idea what is behind your

              ds = dcmread('./5F329172_20170623_CR_2_1_1')
              arr = ds.pixel_array
      

      It's some external library stuff. (And btw I have no idea whether arr.shape[1], arr.shape[0] is the right thing to use. Don't bother to explain, just make sure it's correct for whatever this ds stuff is.)

      Try this:

      import copy
      ...
              arr = copy.copy(ds.pixel_array)
      # or even:
      #        arr = copy.deepcopy(ds.pixel_array)
      

      before you proceed to qimage = QtGui.QImage(arr, ...). Any better, crash-wise?

      D Offline
      D Offline
      darrenleeleelee1
      wrote on last edited by
      #19

      @JonB 72c6dea2-3187-4f9b-b755-d7939e474ce1-image.png
      I add deepcopy,and it also crash. I add some arr attribute for you.
      ed678234-91b9-475e-b889-0117c72ec04c-image.png

      KroMignonK 1 Reply Last reply
      0
      • D darrenleeleelee1

        @JonB 72c6dea2-3187-4f9b-b755-d7939e474ce1-image.png
        I add deepcopy,and it also crash. I add some arr attribute for you.
        ed678234-91b9-475e-b889-0117c72ec04c-image.png

        KroMignonK Offline
        KroMignonK Offline
        KroMignon
        wrote on last edited by KroMignon
        #20

        @darrenleeleelee1 I think you should change your code to:

        qimage = QtGui.QImage(arr.data, arr.shape[1], arr.shape[0], QtGui.QImage.Format_Grayscale16)
        

        It is an old maxim of mine that when you have excluded the impossible, whatever remains, however improbable, must be the truth. (Sherlock Holmes)

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        • KroMignonK KroMignon

          @darrenleeleelee1 I think you should change your code to:

          qimage = QtGui.QImage(arr.data, arr.shape[1], arr.shape[0], QtGui.QImage.Format_Grayscale16)
          
          D Offline
          D Offline
          darrenleeleelee1
          wrote on last edited by
          #21

          @KroMignon I change but still crash...What is the different between arr and arr.data?

          KroMignonK 1 Reply Last reply
          0
          • D darrenleeleelee1

            @KroMignon I change but still crash...What is the different between arr and arr.data?

            KroMignonK Offline
            KroMignonK Offline
            KroMignon
            wrote on last edited by
            #22

            @darrenleeleelee1 said in PyQt QImage cna't copy, crash without error code:

            What is the different between arr and arr.data?

            arr is an instance of numpy.ndarray type, according to your code!
            And arr.data is the data buffer according to numpy documentation ==> https://numpy.org/doc/stable/reference/generated/numpy.ndarray.html

            I think it would be great if you first explain what you want to do.
            Perhaps you should take a look at this python script which converts numpy.ndatarray to QImage and vice versa:
            https://kogs-www.informatik.uni-hamburg.de/~meine/software/vigraqt/qimage2ndarray.py

            It is an old maxim of mine that when you have excluded the impossible, whatever remains, however improbable, must be the truth. (Sherlock Holmes)

            D 1 Reply Last reply
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            • KroMignonK KroMignon

              @darrenleeleelee1 said in PyQt QImage cna't copy, crash without error code:

              What is the different between arr and arr.data?

              arr is an instance of numpy.ndarray type, according to your code!
              And arr.data is the data buffer according to numpy documentation ==> https://numpy.org/doc/stable/reference/generated/numpy.ndarray.html

              I think it would be great if you first explain what you want to do.
              Perhaps you should take a look at this python script which converts numpy.ndatarray to QImage and vice versa:
              https://kogs-www.informatik.uni-hamburg.de/~meine/software/vigraqt/qimage2ndarray.py

              D Offline
              D Offline
              darrenleeleelee1
              wrote on last edited by
              #23

              @KroMignon I saw this before, but I don't know how to apply to uint16.

              KroMignonK 1 Reply Last reply
              0
              • D darrenleeleelee1

                @KroMignon I saw this before, but I don't know how to apply to uint16.

                KroMignonK Offline
                KroMignonK Offline
                KroMignon
                wrote on last edited by
                #24

                @darrenleeleelee1 said in PyQt QImage cna't copy, crash without error code:

                I saw this before, but I don't know how to apply to uint16.

                Which version of Qt-Libs are you using?
                Format_Grayscale16 is only support starting from Qt 5.13 (cf. QImage.Format)

                Because of this note from documentation:

                Constructs an image with the given width , height and format , that uses an existing memory buffer, data . The width and height must be specified in pixels, data must be 32-bit aligned, and each scanline of data in the image must also be 32-bit aligned.

                Perhaps you should specify the number of bytes per line, like this:

                qimage = QtGui.QImage(arr.data, arr.shape[1], arr.shape[0], arr.shape[1]*2, QtGui.QImage.Format_Grayscale16)
                

                It is an old maxim of mine that when you have excluded the impossible, whatever remains, however improbable, must be the truth. (Sherlock Holmes)

                D 1 Reply Last reply
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                • KroMignonK KroMignon

                  @darrenleeleelee1 said in PyQt QImage cna't copy, crash without error code:

                  I saw this before, but I don't know how to apply to uint16.

                  Which version of Qt-Libs are you using?
                  Format_Grayscale16 is only support starting from Qt 5.13 (cf. QImage.Format)

                  Because of this note from documentation:

                  Constructs an image with the given width , height and format , that uses an existing memory buffer, data . The width and height must be specified in pixels, data must be 32-bit aligned, and each scanline of data in the image must also be 32-bit aligned.

                  Perhaps you should specify the number of bytes per line, like this:

                  qimage = QtGui.QImage(arr.data, arr.shape[1], arr.shape[0], arr.shape[1]*2, QtGui.QImage.Format_Grayscale16)
                  
                  D Offline
                  D Offline
                  darrenleeleelee1
                  wrote on last edited by darrenleeleelee1
                  #25

                  @KroMignon said in PyQt QImage cna't copy, crash without error code:

                  arr.shape[1]*2

                  sorry, I read through the QImage API, but I don;t get why I need to add this.
                  After I add this it seems can work.

                  KroMignonK 1 Reply Last reply
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                  • D darrenleeleelee1

                    @KroMignon said in PyQt QImage cna't copy, crash without error code:

                    arr.shape[1]*2

                    sorry, I read through the QImage API, but I don;t get why I need to add this.
                    After I add this it seems can work.

                    KroMignonK Offline
                    KroMignonK Offline
                    KroMignon
                    wrote on last edited by KroMignon
                    #26

                    @darrenleeleelee1 said in PyQt QImage cna't copy, crash without error code:

                    sorry, I read through the QImage API, but I don;t get why I need to add this.

                    Then you don't read carefully ;)
                    The point is when you only specify width and height: The width and height must be specified in pixels, data must be 32-bit aligned, and each scanline of data in the image must also be 32-bit aligned.

                    To avoid this, you can use width, height and scanline length in bytes, which is pixel_per_line x pixel_size:

                    • pixel_per_line is arr.shape[1]
                    • pixel_size is uint16 which are 2 bytes

                    ==> scanline_size = arr.shape[1]*2

                    After I add this it seems can work.

                    Great

                    It is an old maxim of mine that when you have excluded the impossible, whatever remains, however improbable, must be the truth. (Sherlock Holmes)

                    D 1 Reply Last reply
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                    • KroMignonK KroMignon

                      @darrenleeleelee1 said in PyQt QImage cna't copy, crash without error code:

                      sorry, I read through the QImage API, but I don;t get why I need to add this.

                      Then you don't read carefully ;)
                      The point is when you only specify width and height: The width and height must be specified in pixels, data must be 32-bit aligned, and each scanline of data in the image must also be 32-bit aligned.

                      To avoid this, you can use width, height and scanline length in bytes, which is pixel_per_line x pixel_size:

                      • pixel_per_line is arr.shape[1]
                      • pixel_size is uint16 which are 2 bytes

                      ==> scanline_size = arr.shape[1]*2

                      After I add this it seems can work.

                      Great

                      D Offline
                      D Offline
                      darrenleeleelee1
                      wrote on last edited by
                      #27

                      @KroMignon @J-Hilk @JonB @jsulm thanks all u guys!

                      1 Reply Last reply
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