Abstract
A motion vector estimation circuit, necessary for moving picture encoding, is implemented based on the A-D merged circuit architecture using pulse-width modulation(PWM)signals. This circuit contains a PWM memory that stores reference picture data, a distance calculation circuit array, a minimum detecting circuit, a PWM signal shift circuit. The minimum detecting circuit searches the vector with minimum value using a latch comparator. The PWM signal shift circuit enables parallel calculation in search area by shifting PWM signal using a ramp generator and a chopper comparator. We implemented a test chip with 0.6um CMOS technology. This method demonstrate 12.4GOPS processing capability, 380GOPS/W energy efficiency for motion vector estimation at 720pel×480pel, 480frame/s, search area ±2.
