NAME

audim - Auditory images.

CONTENTS

Syntax
Description
Options
Examples
Copyright

audim [options] [file]

This program providesmethods of constructing time-varying auditory images from the output of thecochlear model which are alternatives to the gensai (stabilized auditoryimage) program. Correlograms (ie. row-wise autocorrelation) and row-wiseFourier transform are provided.

The program reads an AIMheader and the output from the genbmm (basilar membrane motion) or gennap(neural activity pattern) programs. This is divided into contiguoustime frames and written on the stdout with an appropriate header as if outputfrom the gensai program. This enables genbmm or gennap output to be divided into timeframes and replayed as a time-varying cartoon by gensai using the "useprevious" option.

Additional processing to each frame is optionally available to computealternative forms of auditory image according to the "image" option.

The options "start" and "length" specify the size of the input.The options "width" and "frstep" specify the frames which are output.The input is divided into frames according to the width option and thefrstep option.

Special option values are:

  length=max      Read all the input from the given start to its end.  width=max       Output framewidth is set equal to the given input                  length, and if this is also "max", then the                  framewidth is the remainder of the input.  frames=1-max    Select the 1st to the last frame inclusively.  frame=4         Select the 4th frame only.
  image=off       Divide the input into frames for replay as a cartoon.  image=acgram    Compute correlogram of each frame.  image=ftgram    Compute power spectrum of each channel of each frame.  image=phgram    Compute phase spectrum of each channel of each frame.

Most options in the input header are copied to the output header.This enables options which are needed for the eventual displayto pass straight through. Some options are set so that they can overridethe input header. For example, the display option is set on to enabledisplay even when input has display=off. The animate option can be set oneven when the input has animate=off.Parts of the header are changed for the new sai format:(frames, frameshift, framewidth, frameheight, framebytes).

Certain display parameters have different default values for differentapplications. The gensai display parameters should be set to the appropriatevalues, in order to plot the cartoon on the same scale. For example:when the source application is gennap, set gensai top=1000,when the source application is genbmm, set gensai bottom=-100.

1. To convert gennap output to multiple animated frames:
gennap len=16ms display=off output=stdout file |     audim image=off width=8ms frstep=0.2ms anim=on > file.saigensai useprev=on file             -(for landscape plot)genspl useprev=on pensize=2 file   -(for spiral plot)
(Note: spirals look better in a square box, so you might use options:    dencf=1 width=500 height=500 )
2. An animated normalized correlogram from gennap output:
gennap len=64ms output=stdout display=off file |     audim norm=on anim=on > file.saigensai useprev=on top=1000 file             -(for landscape plot)genspl useprev=on top=1000 pensize=2 file   -(for spiral plot)

acgram ftgram edframe naptosai

Copyright (c) Applied Psychology Unit, Medical Research Council, 1995

Permission to use, copy, modify, and distribute this software without feeis hereby granted for research purposes, provided that this copyrightnotice appears in all copies and in all supporting documentation, and thatthe software is not redistributed for any fee (except for a nominalshipping charge). Anyone wanting to incorporate all or part of thissoftware in a commercial product must obtain a license from the MedicalResearch Council.

The MRC makes no representations about the suitability of thissoftware for any purpose. It is provided "as is" without express orimplied warranty.

THE MRC DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDINGALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALLTHE A.P.U. BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGESOR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THISSOFTWARE.