Without eye tracking won the viewer be able to see that the images have variable resolution?
In general, if the viewer is not looking at a foveation region, the reduced resolution due to the foveation will be visible. However, keep in mind that the gain to the viewer is increased resolution in the regions of interest (or increased frame rate). Often the increased resolution (or frame rate) is much more important that the loss of resolution away from the regions of interest. Our experience is that mouse-controlled foveation is a smooth and natural operation for the viewer. Furthermore, time delays in transmitting the mouse coordinates to the sender is not a problem here, because the eye movements are uncoupled from the position of the foveation region.
