IP FT - Interpolate/Resize - using Fourier Transform ||

(06/02/11)

PURPOSE

Takes input image/volume of any dimension and creates interpolated image/volume of any dimension. Creates enlarged image/volume using zero padding in Fourier Space.   Example.

SEE ALSO

IP FS [Interpolate/resize image/volume - using Fourier based cubic spline ||]
IP [Interpolate/Resize using bilinear/trilinear interpolation]
IP T [Interpolate/Resize - using Triangular interpolation]
DC [Decimate image/volume]

USAGE

.OPERATION: IP FT

.INPUT FILE: PIC001
[Enter name of file containing input image/volume.]

.INTERPOLATED OUTPUT FILE: IMG022
[Enter name of file where output image/volume is to be placed.]

If input file is an image, SPIDER asks:


.OUTPUT DIMENSIONS, NS, NY: 72, 48,
[Enter interpolated X & Y dimensions for the output image]

If input file is a volume, SPIDER asks:


.DIMENSIONS, NS, NY, NZ: 72, 48, 50
[Enter interpolated X, Y and Z dimensions for the output volume.]

NOTES

  1. Interpolation is exact in a sense that the total energy of an image is preserved. Note that the interpolation is not exact on the old grid!

  2. Pixel size in header is updated.

  3. This is a new name for: 'FP' operation, code is the same as that operation.

SUBROUTINES

INTERPS, FINT, FINT3

CALLER

UTIL2