Patent Document ID: 8582869
Application ID: 13353804
Patent Status: 1

Claim One:
1. A method of processing in a data processor an input multidimensional dataset represented by one dimensional subsets each comprising a block of data of size N stored in a digital memory so as to provide an interpolation of the data stored therein to produce a dataset of size M, the method comprising: providing a data processor; transforming in the data processor, for each of said subsets, the block of data into the frequency domain to obtain a set of direct transform coefficients C={a k } k=0 N for a desired interpolator type; determining in the data processor an appropriate inverse discrete trigonometric transform for using said set of coefficients to calculate an interpolated dataset F n = ∑ k = 0 N ⁢ A ⁡ ( n , k ) ⁢ α k , where n=0, 1, M, and A(n,k) is a non-square matrix of size ˜M×N, said determining including: reducing recursively the calculation of the transform to a chain of smaller transforms of size (M/2)×(N/2) until a size (qm×q) is reached, where m=M/N and q is one of the integers 2, 3 and 4; and calculating each of the smaller transforms directly using a family of interpolators corresponding to the symmetry properties of smaller, non-square transform matrices that result from the recursive reduction process; and computing and assembling in the data processor an output dataset of size M from the results of the calculated smaller transforms to store in a digital memory the interpolated output dataset.