Patent ID: 6546120
Filing Date: 2003-04-08
Classification: G06T,H04N

Abstract:
A method of representing correspondence between two images as a function of mapping a position set on one image to a position set to the other and finding a mapping parameter for defining the function, thereby obtaining motion between the images, said method comprising:(1a) error operation step of, for a plurality of local areas into which an image is divided, calculating the local area correspondence between two different images as an error and finding a displacement between the local areas reaching the minimum error and an error value in the proximity of the displacement; (1b) error function operation step of finding for each local area a quadratic error function with displacement as a variable from the displacement reaching the minimum error and the error value in the proximity of the displacement; and (1c) nonlinear iteractive minimization step of again representing the sum total or partial sum of the quadratic error functions in a parameter representing a function and executing nonlinear iteractive minimization for the parameter for finding a parameter, said nonlinear iteractive minimization step comprising: (1c-1) partial differential operation step of finding a first-order partial differential vector and a second-order partial differential matrix concerning the parameter of the sum total or partial sum of the quadratic error functions; (1c-2) second-order partial differential matrix change step of increasing diagonal elements of the second-order partial differential matrix in response to the degree to which the minimization in each repetition falls below a predetermined expected value; and (1c-3) parameter change step of multiplying the first-order partial differential vector by an inverse matrix of the modified second-order partial differential matrix for providing a parameter increment or decrement, wherein each parameter increment or decrement provided by iterating said partial differential operation step, said second-order partial differential matrix change step, and said parameter change step is added sequentially for changing the parameter for executing the minimization.