Audification is an

auditory display Auditory display is the use of sound to communicate information from a computer to the user. The primary forum for exploring these techniques is the International Community for Auditory Display (ICAD), which was founded by Gregory Kramer in 1992 ...

technique for representing a sequence of data values as sound. By definition, it is described as a "direct translation of a data waveform to the audible domain." Audification interprets a data sequence and usually a

time series In mathematics, a time series is a series of data points indexed (or listed or graphed) in time order. Most commonly, a time series is a sequence taken at successive equally spaced points in time. Thus it is a sequence of discrete-time data. Exa ...

, as an audio

waveform In electronics, acoustics, and related fields, the waveform of a signal is the shape of its graph as a function of time, independent of its time and magnitude scales and of any displacement in time.David Crecraft, David Gorham, ''Electronic ...

where input data are mapped to

sound pressure Sound pressure or acoustic pressure is the local pressure deviation from the ambient (average or equilibrium) atmospheric pressure, caused by a sound wave. In air, sound pressure can be measured using a microphone, and in water with a hydrophone ...

levels. Various

signal processing Signal processing is an electrical engineering subfield that focuses on analyzing, modifying and synthesizing ''signals'', such as audio signal processing, sound, image processing, images, and scientific measurements. Signal processing techniq ...

techniques are used to assess data features. The technique allows the listener to hear periodic components as frequencies. Audification typically requires large data sets with periodic components. Audification is most commonly applied to get the most direct and simple representation of data from sound and to convert it into a visual. In most cases it will always be used for taking sounds and breaking it down in a way that we can visually understand it and construct more data from it.

History

The idea of audification was introduced in 1992 by Greg Kramer, initially as a sonification technique. This was the beginning of audification, but is also why most people to this day still consider audification a type of sonification. The goal of audification is to allow the listener to audibly experience the results of scientific measurements or simulations. A 2007 study by Sandra Pauletto and Andy Hunt at the

University of York , mottoeng = On the threshold of wisdom , established = , type = Public research university , endowment = £8.0 million , budget = £403.6 million , chancellor = Heather Melville , vice_chancellor = Charlie Jeffery , students ...

suggested that users were able to detect attributes such as noise, repetitive elements, regular oscillations, discontinuities, and signal power in audification of time-series data to a degree comparable with visual inspection of

spectrograms A spectrogram is a visual representation of the spectrum of frequencies of a signal as it varies with time. When applied to an audio signal, spectrograms are sometimes called sonographs, voiceprints, or voicegrams. When the data are represen ...

Applications

Applications include audification of seismic data and of human neurophysiological signals. An example is the esophageal

stethoscope The stethoscope is a medical device for auscultation, or listening to internal sounds of an animal or human body. It typically has a small disc-shaped resonator that is placed against the skin, and one or two tubes connected to two earpieces. ...

, which amplifies naturally occurring sound without conveying inherently noiseless variables such as the result of gas analysis.

Medicine

Converting

ultrasound Ultrasound is sound waves with frequency, frequencies higher than the upper audible limit of human hearing range, hearing. Ultrasound is not different from "normal" (audible) sound in its physical properties, except that humans cannot hea ...

to audible sound is a form of audification that provides a form of echolocation. Other uses in the medical field include the

and the audification of an

EEG Electroencephalography (EEG) is a method to record an electrogram of the spontaneous electrical activity of the brain. The biosignals detected by EEG have been shown to represent the postsynaptic potentials of pyramidal neurons in the neocortex ...

Music

The development of

electronic music Electronic music is a genre of music that employs electronic musical instruments, digital instruments, or circuitry-based music technology in its creation. It includes both music made using electronic and electromechanical means ( electroac ...

can also be considered the history of audification. This is because all electronic instruments involve electric process audified using a loudspeaker.

Seismology

Audification is of interest for research into Auditory Seismology. It is used in earthquake prediction. Applications include using seismic data to differentiate bomb blasts from

earthquakes An earthquake (also known as a quake, tremor or temblor) is the shaking of the surface of the Earth resulting from a sudden release of energy in the Earth's lithosphere that creates seismic waves. Earthquakes can range in intensity, from ...

. The technique presents sound waves of earthquakes alongside a visual representation. The addition of audio allows both the eye and ears to contribute to better understanding.

NASA

NASA has used audification to represent radio and plasma wave measurements.

Sonification

Both sonification and audification are representational techniques in which data sets or its selected features are mapped into audio signals. However, audification is a kind of sonification, a term which encompasses all techniques for representing data in non-speech audio. Their relationship can be demonstrated in the way data values in some sonifications that directly define audio signals are called audification.

References

{{Reflist Multimodal interaction Display technology Auditory displays User interface techniques