Last.fm – the Blog

Edit: we’ve updated the image of the Audio Flower to give you a better idea of what it visualises.

We’ve been thrilled with the all support we’ve been getting from users who are helping us rate the tempo of music tracks in our Speedo experiment, thanks! Now we’d like to ask you to help us with another fun music experiment for a new project called Audio Flowers.

We are currently doing some research into new techniques to measure structural change (or “complexity”) in rhythm, harmony and timbre directly from mp3 files. The measurements we take from a song are then summarised to produce a little image: an Audio Flower like the one below.

Here’s a description of what the ‘flower’ above is showing us.

We can tell straight away that Mr. Roboto by Styx has strong long term changes: the end of the red rhythm petal is quite thick – as are ends of the harmony and timbre petals. In fact, this suggests that the song is organised in distinctive parts.
Let’s have a closer look at the red rhythm petal then: towards the middle of the petal, its main, opaque part is much thinner then at the tip. This indicates that for most of the song there is little mid-term rhythmic change. However, you can see from the translucent part that there must be some sections of the song with atypically many rhythmic changes … find out if you agree here (link to YouTube).

Find more examples here.

We think this visualisation could be used by other people who’d like to find out about the complexity of music, and that’s why we want to publish the technique at an international scientific conference later this year.

But here’s the problem: although we’re quite happy with our signal processing magic (which automatically guesses the amount of structural change going on in the music), we don’t know yet if human beings like yourself feel the same way as the computers… and we need to know that in order to convince the scientists to publish our results.

The new Audio Flowers demo is similar to the Speedo demo; just listen to short excerpts of tracks on screen and answer a couple of simple questions.

We really hope you can help us again by listening and voting! If you like the Audio Flowers, please tell us, and we’ll see if we can make more of them available for your favourite songs.