Description

S3L_conv computes the 1D or 2D convolution of a signal represented by a parallel array using a filter contained in a second parallel array. The result is stored in a third parallel array. These parallel arrays are described by the S3L array handles: a (signal), b (filter), and c (result). All three arrays are of the same real or complex type.

For the 1D case, if the signal a is of length ma and the filter b of length mb, the result of the convolution, c, will be of length ma + mb - 1. In the 2D case, if the signal is of size [ma,na] and the filter is of size [mb,nb], the result of the convolution is of size [ma+mb-1,na+nb-1].

Side Effects

Because a and b are used internally for auxiliary storage, they may be destroyed after the convolution calculation is complete. If the contents of a and b must be used after the convolution, they should first be copied to temporary arrays.

S3L_conv is most efficient when all arrays have the same length and when this length can be computed efficiently via S3L_fft, or S3L_rc_fft. See "S3L_fft " and "S3L_rc_fft and S3L_cr_fft " for additional information.

Restriction

The dimensions of the array c must be such that the 1D or 2D complex-to-complex FFT or real-to-complex FFT can be computed.