Usage Example - Operation: 'FQ NP'

Filter - Quick Fourier Filter, No Padding

Procedure used: fqnp.spi

.OPERATION: FQ NP ;   Quick Fourier Filter - No Padding
.INPUT FILE: sav_pp ;   Image (input)
.OUTPUT FILE: fqnp ;   Filtered image (output)
.FILTER TYPE (1-10): 2 ;   High pass filter
.FILTER RADIUS (IN FREQUENCY OR PIXEL UNITS): 10 ;   Radius in pixels


INPUT IMAGE HIGH PASS OUTPUT IMAGE
sav_pp fqnp


Further Examples of Filtration (Note: 0.5 = Nyquist frequency)

LOW-PASS Radius (Freq.): 0.09
HIGH-PASS Radius (Freq.): 0.45
GAUSSIAN LOW-PASS Radius (Freq.): 0.06
GAUSSIAN HIGH-PASS Radius (Freq.): 0.45
FERMI Radius (Freq.): 0.09
BUTTERWORTH LOW-PASS Lower Freq.: 0.06 Upper Freq.: 0.12
BUTTERWORTH HIGH-PASS Lower Freq.: 0.4 Upper Freq.: 0.5
RAISED COSINE LOW-PASS Lower Freq.: 0.06 Upper Freq.: 0.12
RAISED COSINE HIGH-PASSLower Freq.: 0.4 Upper Freq.: 0.5

Image Filtration

Volume Filtration