Patent ID: 6208386
Filing Date: 2001-03-27
Classification: H04N

Abstract:
Apparatus for automatic replacement of a billboard in a video image comprising:an automatic camera orientation measurement apparatus including motion measurement means operative to measure the Field of View (FOV) of the TV camera relative to a known reference position; andan image processing means for processing video signals generated by the TV camera, wherein said processing means includes calibration means for periodically automatically calibrating the motion measurement means, the calibration means including a fine adjustment image processing means for perspectively transforming the current video image to provide an estimated transformed model, means for storing a replica of the billboard image, means for comparing the perspectively transformed video image with the stored replica to provide a residual video field, means for solving residual distortion between the transformed model and the residual video field and means for updating the estimated transformation by means of the residual distortion to provide a calibration correction factor.