Patent ID: 8160388
Filing Date: 2012-04-17
Classification: G06T

Abstract:
1. A method for selectively transforming a spatially varying optical characteristic (F) of an image in an array of pixels, said array characterized by NY rows of pixels oriented in an X direction and NX columns of pixels oriented in a Y direction, said NX and NY each at least 5, said optical characteristic denoted as F(x,y) such that x and y are indexes of pixels in the X and Y directions, said method implemented by execution of instructions by a processor of a computer system, said instructions being stored on computer readable storage media of the computer system, said method comprising: segmenting the array of pixels into at least one stripe, wherein each stripe consists of a contiguous sequence of rows of the array of pixels; transforming the rows of each stripe, said transforming comprising determining a two-dimensional convolution C(x, y) of F at only selected pixels (x, y) in each stripe, wherein C(x, y) is a function of a product of a horizontal kernel h(x) and a vertical kernel v(y), said h(x) and v(y) each of dimension n≧3, wherein said determining C(x, y) at each selected pixel (x, y) in each row of each stripe comprises: determining n vertical convolutions such that each vertical convolution is equal to a scalar product of F and v(y) in a kernel space surrounding (x,y), forming an array (V) of dimension n from the n vertical convolutions, and computing C(x,y) as a scalar product of V and a constant horizontal vector (H) formed from h(x); after said transforming, collecting the stripes to form a transformed image; storing and/or displaying the transformed image, wherein a current row of a current stripe of the at least one stripe comprises a contiguous ordered sequence of a selected pixel (S