DF - Density Foldover

(1/14/90)

PURPOSE

Expands display density by re-mapping the density range, yielding multiple output density assignments. The result contains equal-density contours along which the foldover occurs ("equidensitometry").   Example.

USAGE

.OPERATION: DF
FC FC E

.INPUT FILE: PIC001
[Enter the name of the image file to be remapped.]

.OUTPUT FILE: OUT001
[Enter name of output file where result is to be put.] SPIDER will output the image range (FMIN ... FMAX) and the offset used for normal display (=FMIN).]

.SCALING FACTOR: 3.5
[Density scaling factor by which each pixel will be multiplied according to

TEMPPIXEL = (OLDPIXEL-OFFSET) * SCALE.

From this, the output is computed according to

NEWPIXEL = MOD(TEMPPIXEL,DIFF)

where DIFF is FMAX-FMIN for the image before re-scaling.]

.OFFSET: 0.15
[Enter offset constant, to be subtracted from the image before rescaling. Unless you want to truncate part of the density range, use 0.0]

SUBROUTINES

DENOV

CALLER

UTIL2