Using FREngine Visual Components in Qt has not been tested, but it should be possible.
- http://qt-project.org/doc/qt-4.8/activeqt-container.html - general information on ActiveX controls accessed within QT.
- http://qt-project.org/doc/qt-4.8/qaxwidget.html - documentation on QAxWidget class which is most likely to be used to wrap up components such as ImageViewer.
- http://qt-project.org/doc/qt-4.8/activeqt-webbrowser.html - an example of ActiveX control for Internet Explorer being used with QT. Since Visual Components of ABBYY FineReader Engine work as ActiveX controls, we would recommend you take the time to study this sample, reproduce it and then use a similar approach to integrate ABBYY ImageViewer into your program.