Rasterscan display with adaptive decay

摘要

Apparatus for manipulating numerical values stored in a memory comprises a modify device for receiving numerical values from the memory and returning numerical values to the memory. The modify device has at least a first state in which it modifies a numerical value received from the memory in a predetermined fashion before returning the numerical value to the memory and a second state in which it does not modify a numerical value received from the memory in the predetermined fashion before returning the numerical value to the memory. The apparatus also comprises a characterizing device for examining at least some of the numerical values and calculating at least one number that defines a property of the examined numerical values. The characterizing device is connected to the modify device for placing the modify device in the first state or the second state depending on the value of the calculated number.