Detecting user input provided to a projected user interface

Apparatuses and methods are provided for determining whether a user intends to provide an input using an image of a control appearing on a surface. An apparatus may include first and second cameras to capture set and second sets of two or more images of the surface, and a unit to determine whether various conditions are true. A first condition is that a particular number of skin-color pixels are present within one cell of the two or more images. A cell location substantially coincides with the image of the control. A second condition is that the skin-color pixels persist for at least a particular time period. A third condition is that a region of skin-color pixels has a substantially rectangular shape. A fourth condition is that corresponding edges of skin-color pixels in the first and second sets of images are within a predefined offset distance. Additional conditions are disclosed.