Patent ID: 6212288
Filing Date: 2001-04-03
Classification: G06T

Abstract:
A circuit for determining the velocity of an image feature between a first position and a second position, comprising:a first circuit for detecting the image feature in the first position, a first circuit generating a first signal in response to the detection of the image feature at the first position;a second circuit generating a second signal in response to the detection of the image feature at the second position;a third circuit for converting the first signal to a third signal, the third signal being representative of the time lapse from the detection of the image feature at the first position, the third signal being a time-invariant and contrast-invariant signal, the third circuit being a first pulse-shaping circuit;a fourth circuit for converting the second signal to a fourth signal and the fourth signal being representative of the time lapse from the detection of the image feature at the second position, the fourth signal being a time-invariant and contrast-invariant signal, the fourth circuit being a second pulse-shaping circuit;a fifth circuit for receiving the third and second signals, the fifth circuit generating a fifth signal in response to the third and second signals, the fifth signal being representative of the velocity of the image feature moving from the first position to the second position, anda sixth circuit for receiving the fourth and first signals, the sixth circuit generating a sixth signal in response to the fourth and first signals, the sixth signal being representative of the velocity of the image feature moving from the second position to the first position.