One more suggestion: if the picture is meant to be a background for something else (like a computer desktop, a printed page or a work of art), then the "something else" forms the foreground of the resulting work, and the picture in the background should not excessively distract the viewer from it.  Thus, a completely blurred or defocused picture may be exactly what the overall composition needs.

It's also worth noting that not all blur is the same: for example, motion blur only loses detail along the direction of motion, but retains variations orthogonal to it.  Besides, blurring can also add detail.  For example, a defocused photo can show the camera's bokeh, while motion blur adds information about the movement of the subject (and/or the camera).  An extreme example would be star trail photography, where the motion blur is provided by the Earth's rotation.  Obviously, these images are blurred by definition &mdash; but that blur is precisely the subject of the image.

Why would one shoot a fully blurred picture?
How do I make animated menus with cocos2d, I just want to animate the buttons and not the entire scene. Effects I look for is flipping buttons (like the back of the button is the next menu), buttons that retract once selected and re appear with new button.

Basically what I ask for is cool effects between menu transitions.
