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How It Works
If you want to find out how Intrasonics can help you engage with your audience or customers, then we want to hear from you...

How It Works - In Summary

Intrasonics is the leading technology for embedding inaudible codes in audio and recovering it acoustically. Independent tests by our customers have shown that we consistently out-perform the alternative solutions.
Tricking the Human Brain

Intrasonics' technology exploits the way that the human brain processes sensory information. The brain is extremely good at filtering out irrelevant information, so that it has less work to do in telling us what we need to know about our immediate environment.
When we hear sound, what we actually hear is not the same as that which would be picked up by a microphone. In a closed environment, no matter how large, every sound has a direct path to a listening device (whether an ear or microphone) and a very large number of indirect paths. These indirect paths are echoes, starting with single and double reflections off walls and objects but continuing with multiple reflections (reverberations) that taper to zero in intensity over time.
Our brains are able to filter out the vast majority of natural echoes so that we can concentrate only on the direct sound paths. If we could suddenly hear all the single, double and multiple echoes, it would not be very pleasant! Intrasonics exploits the filtering characteristics of the human brain by using a system of artificial echoes to hide data within audio.
Inserting Artificial Echoes into Audio

To create artificial echoes, Intrasonics modifies an audio track in such a way that when played in an open and flat outdoor space, the tracks would sound to a microphone like there were actual single and double reflections of the sound waves present. To the human ear, however, the modified audio sounds just the same as the original because the human brain filters out any extraneous echoes (whether they are real or artificial).

Following many years of research, Intrasonics has devised sophisticated digital signal processing techniques for embedding data bits into audio by adding artificial echoes.
Intrasonics technology embeds the numeric information in N-bit blocks and each of these blocks is called a trigger code. The process of inserting codes through artificial echo modulation is called "encoding".


Although inaudible to humans and animals (due to the brainís natural filtering ability), the artificial echoes inserted into audio during the encoding process can be picked up by microphones such as those on smartphones and tablet devices. Using further digital signal processing algorithms, artificial echoes are detected and decoded back into the corresponding codes on the mobile device.
Step One:
Install our demo app on your iPhone. It's on the Apple App Store:
Click to Open iTunes & Download Euphonium
Step Two:
Run the app on your iPhone.
Step Three:
Turn on your computer speakers and see what happens when you watch one of our Demo Videos
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