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     Charles P. Peterson  (


     GFFT is an audio spectrum analysis program with many features.  By
     operating from stored sound sample files, it can provide high
     resolution and accuracy, and has no specific CPU performance

     Audio spectrum analysis allows you to see the frequency content of a
     sound file and how it varies over time.  This can be used to help
     understand sounds such as acoustical instruments and speech,
     and also to evaluate and adjust loudspeakers and other sound
     reproducing equipment.  

     GFFT accepts 8, 12, or 16-bit data in in IFF 8SVX, AIFF, and AVR
     formats, or in unformatted files.  It can also accept data points
     entered through a console in floating-point.  The number of frequency
     bins and smoothing points is limited only by available memory; there
     is no limit to the length of the sound data which can be analyzed and

     Both a Workbench GUI and a CLI interface are provided.  There is
     built-in help for both interfaces using a help file that can also be
     read as a user manual.

     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 to a console or file.
     GFFT can perform a 2D (Amplitude vs Frequency) or 3D (Amplitude vs
     Frequency vs Time) analysis.  It allows the selection of logarithmic X
     and/or Y axes, the dB scaling of X, and arbitrary 3D rotation.  It can
     show multiple spectra in the same plot, or append spectral data bands
     from earlier sessions.

     There are 8 selectable data window types, including Blackman-Harris 92
     dB, which has very low sidelobe artifacts.  A special weighting can be
     applied for pink noise testing.  Smoothing, calibration, ranging, and
     quantization are also available.


     GFFT is available for anonymous FTP on Aminet sites such as (




     gfft-1.12.lha         (302760 bytes)
     gfft-1.12.readme      (1869 bytes)


     Workbench 1.3 (V34) or higher and 1.5M total RAM.  Will run on some
     systems with 1M RAM with reduced capabilities.  Recommended: Workbench
     2.0 (V37) or higher, 3M or more RAM, and harddrive or second floppy.
     Larger amounts of memory will enable you to analyze using more
     frequency bins.

     Gnuplot 3.0 or higher is required; Gnuplot 3.4 or higher is required
     for the Hidden3D feature (only).  Gnuplot is available on Aminet (see
     below for an example) and on some Fish disks and CD-ROMs.

          Aminet (e.g.

               pub/aminet/util/gnu/gnufit12gp35.lha   (Gnuplot 3.5)

               pub/aminet/util/gnu/gnuplot-3.5.lha    (Gnuplot 3.5)

          AmigaLibDisk (also GoldFish and FrozenFish CD-ROMs)
               AmigaLibDisk 701                        (Gnuplot 3.2)


     GFFT itself is free; you do not have to pay for using it.

     Donations are encouraged to help support future development.

     An e-mail message or postcard sent to the author will provide moral
     support and will be appreciated even in the absence of a monetary

     Additional support services are also available, including packaged
     'Deluxe' distributions:

     Copy of latest GFFT 1.x Deluxe Distribution (with additional documents,
          screen shots, and extras--1 disk)............$15 ($20 outside USA)

     Copy of latest GFFT 1.x Expanded Deluxe Distribution (with
          Gnuplot, POST, notes & more--5 disks)........$25 ($40 outside USA)

     Purchasing either Deluxe Distribution or making a minimum $15 donation
     will entitle user to 1 hour of support from the author within one year
     and notification when the next release becomes available.  Additional
     support is available for $15/hour.  It is also possible to make a
     contingent donation to encourage the development of a specific
     enhancement.  See the README file in the program archive for further


     GFFT is Copyright (C) 1994 Charles P. Peterson and is distributed
     under a GNU General Public License.  Full SAS/C source code for GFFT
     is included in all distributions.  The 'Network' distribution of GFFT
     available on Aminet contains only GFFT and freely distributable

     The 'Deluxe' distributions (available only on disk from the author)
     include additional material which is not freely distributable.


     Two binaries are provided; one for 68000 and one for 68020 w/68881 or

     GNUPLOT is invoked and controlled by GFFT.  You do not have to learn
     how to use GNUPLOT except to fully utilize the Postscript and TeX
     output options.

     GFFT is not currently a part of project GNU and the Free Software
     Foundation does not necessarily know anything about it.

     At this time, GFFT is only available for Amiga.

     Other programmers are encouraged to read and learn from the GFFT
     source code and contribute enhancements or ports if they are able to
     do so.  Income from GFFT donations may be shared with program

     The GFFT Network Distribution may be included with other freeware and
     commercial products under the terms of the GNU General Public License.
     There is no stated limit as to what may be charged for transferring a
     copy of GFFT either by itself or in combination with other works,
     products, or services.