.INPUT FILE: PIC001
[Enter the name of the file to be interpolated.]
.OUTPUT FILE: IMG025
[Enter the file where the interpolated image is to be
kept.]
.ENTER DIMENSIONS, NSAM,NROW: 128,128
[Enter the dimensions of the interpolated image.]
NOTES
This operation can be used for either interpolation or
extrapolation.
The output image does not have to have the same
proportions (ratio NSAM/NROW) as the input picture.
For a rectangular input image, only the new side
length (NSAM) of the output image need be entered.
The other side length (NROW) will then be computed
assuming the same proportions as the input image. For
example, let the input image have the size 60x40.
Then the sequence
.ENTER DIMENSIONS, NSAM, NROW: 120
will have the same effect as
.ENTER DIMENSIONS, NSAM, NROW: 120,80
For an output picture with dimensions exactly two times
smaller than those of an input picture addition of
four neighbouring pixels is done. The resulting picture
contains frequencies up to 0.25 (roughly) and has improved
SNR (two times).
For an output picture with dimensions exactly four times
smaller than those of an input picture addition of sixteen
neighbouring pixels is done.
The triangular interpolation scheme is used for any image
sizes.
This operation is for 2-D image only, not for volumes.
