An information processing system includes a projection unit that projects
at least image data for calibration, an image data capturing unit that
captures projection image data projected by the projection unit, a
specifying unit that specifies positions of points to be calibrated with
the image data captured by the image data capturing unit, the positions
of the points to be calibrated representing a shape of the image data for
calibration, a calculation unit that calculates parameters to transform
the positions of the points to be calibrated on to the positions of
reference points, and a transformation unit that transforms the image
data captured by the image data capturing unit with the parameters.