2D Convolution and Down Sampling Operator

DESCRIPTION:

Horizontal or vertical convolution and down sampling operator.

USAGE:

hor.convdown(x, filter, boundary="periodic", fast=F) 
ver.convdown(x, filter, boundary="periodic", fast=F) 

REQUIRED ARGUMENTS:

x
an image or a matrix.
filter
a vector of filter coefficients.

OPTIONAL ARGUMENTS:

boundary
a character string or a character vector of length two giving the name(s) of the boundary rule. All the boundary rules listed for convdown are available except for "infinite". See convdown for the definitions of these rules.
fast
logical flag indicating if fast algorithm should be used.

VALUE:

If nrow(x) is even, hor.convdown returns an nrow(x)/2 by ncol(x) matrix. If nrow(x) is odd, see convdown for details on the number of rows of output. If ncol(x) is even, ver.convdown returns a nrow(x) by ncol(x)/2 matrix. If ncol(x) is odd, see convdown for details on the number of columns of output.

SEE ALSO:

, , , , .