CCD devices are based on handling charge packets in potential wells, generated by applying voltage to the gate of a MOS capacitor structure. There is no controllable static charge distribution mechanism in CCD to enable developing spatial processing the same as in CMOS. However, a charged packet stored in a potential well can be distributed to its neighbors through a series of clocks. In fact a major factor determining the function of CCD devices is the clocking sequence and method. Unfortunately, although it is possible to perform charge redistribution, the only operations easily feasible are addition and subtraction of charge packets. There are some vision chips using mixed CCD/CMOS circuits [Dron 93, Keast and Sodini 92]. CCDs offer easier solutions for some operations. For example, in a smoothing CCD vision chip the smoothing width can be increased by only leaving the circuit to operate over more clock cycles. In other words, CCDs are capable of iterating a function without additional demands on space.