The DS9 backend contains 2 renderers, VMR9 and softrenderer. In my Windows XP installation the VMR9 one doesn't work (can be seen by a warning "the video widget could not be initialized correctly" when the video widget is created) The softrenderer didn't work at all until I edited the file src/3rdparty/phonon/ds9/videowidget.cpp and commented out the following function from VideoWindow:
how can we switch between these two renderers?