Abstract: An apparatus for coding an image while scrambling the image by randomizing pixel values includes a scrambling unit which scrambles an image by utilizing an encryption function to compute a displacement of a pixel value to be randomized in response to a displacement of a previously randomized pixel value.

Abstract: In an electrostatic head, each of electrostatic actuators includes a diaphragm doubling as or including a first electrode forming a wall surface of a discharge room communicating with a nozzle discharging a drop, and a second electrode opposing the first electrode. The diaphragm is deformed by generating an electrostatic force between the first electrode and the second electrode. The first electrodes or the second electrodes of the electrostatic actuators are combined electrically. Differently polarized potentials are applied to the first electrode and the second electrode upon discharging the drop.