2D Down/Up Sampling Operator

DESCRIPTION:

Splits a 2D image into 4 subbands or merge 4 subbands into a 2D image.

USAGE:

quad.down(x, fl.hor, fh.hor, fl.ver, fh.ver, boundary="periodic") 
quad.up(x, fl.hor, fh.hor, fl.ver, fh.ver, boundary="periodic") 

REQUIRED ARGUMENTS:

x
an image or a matrix.
fl.hor
low-pass quadrature mirror filter for horizontal.
fh.hor
high-pass quadrature mirror filter for horizontal.
fl.ver
low-pass quadrature mirror filter for vertical.
fh.ver
high-pass quadrature mirror filter for vertical.

OPTIONAL ARGUMENTS:

boundary
a character string giving the name of the boundary rule. All the boundary rules listed for dwt are available except for "infinite". See dwt for the definitions of these rules.

VALUE:

a matrix of the same dimension as x.

SEE ALSO:

, , .