Hi,

I mean post the actual compiler output.
Qt Code: 
  1. Error    1    error C2065: 'GL_BGR' : identificador no declarado    c:\QOpenCVCamera\QOpenCVCamera\QOpenGLWidget.cpp    56
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And the GL includes you have in your code.
Qt Code: 
  1. #include <QtOpenGL>
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I only included the QtOpenGL header that I think that is the header used by Qt.

Thanks,