GFFT is an FFT-based spectrum analysis program with many options and features
including optional logarithmic axes, calibration, smoothing, 3D (vs time)
analysis, and many FFT window types. By operating from stored sample data
files (8 or 16-bit in many formats), it offers higher resolution and/or
accuracy than real-time analyzers. High quality spectrum plots can be produced
on screen, plotter, or printer, or saved to Postscript or TeX files. Spectral
data can also be output in text form. (GNUPLOT is required and is controlled
automatically.) Several spectra can be shown in the same plot, and spectral
data bands from earlier sessions can be appended. GFFT can be operated from
either a Workbench GUI or from a CLI in interactive or batch modes. It has
built-in help for all operating modes. Version 1.12. C source is included. GNU
Public License. Author: Charles P. Peterson