PROCESSING CIRCUIT OF DIGITAL SIGNAL

摘要

PURPOSE:To control contrast without changing luminance by setting the center value of amplitude control to an offset value, subtracting the offset value before multiplication, weighting the subtracted value by a 2'S complement multiplier around ''0'', and adding an offset value to the weighted signal by an adder. CONSTITUTION:An input signal 1 consisting of a binary signal having n bits is inputted to a subtracting circuit 2 to subtract an offset value 3 from the input signal. The subtracted result is inputted to the 2'S complement multiplier 4 to set an optional offset value to ''0''. On the other hand, a binary signal indicating the capacity of control is inputted from a factor setting circuit 6 to the 2'S complement multiplier 4 on the basis of a control signal 5. The signal weighted by the multiplier 4 is applied to an adder 7 to add an offset value 8 to the input signal.