Tag Archives: sonification

Kinectofon: Performing with shapes in planes

2013-05-28-DSCN7184Yesterday, Ståle presented a paper on mocap filtering at the NIME conference in Daejeon. Today I presented a demo on using Kinect images as input to my sonomotiongram technique.

Title
Kinectofon: Performing with shapes in planes

Links

Abstract
The paper presents the Kinectofon, an instrument for creating sounds through free-hand interaction in a 3D space. The instrument is based on the RGB and depth image streams retrieved from a Microsoft Kinect sensor device. These two image streams are used to create different types of motiongrams, which, again, are used as the source material for a sonification process based on inverse FFT. The instrument is intuitive to play, allowing the performer to create sound by “touching’’ a virtual sound wall.

Reference
Jensenius, A. R. (2013). Kinectofon: Performing with shapes in planes. In Proceedings of the International Conference on New Interfaces For Musical Expression, pages 196–197, Daejeon, Korea.

BibTeX

@inproceedings{Jensenius:2013e,
   Address = {Daejeon, Korea},
   Author = {Jensenius, Alexander Refsum},
   Booktitle = {Proceedings of the International Conference on New Interfaces For Musical Expression},
   Pages = {196--197},
   Title = {Kinectofon: Performing with Shapes in Planes},
   Year = {2013}
}

kinectofon_poster

ImageSonifyer

ImageSonifyer

Earlier this year, before I started as head of department, I was working on a non-realtime implementation of my sonomotiongram technique (a sonomotiongram is a sonic display of motion from a video recording, created by sonifying a motiongram). Now I finally found some time to wrap it up and make it available as an OSX application called ImageSonifyer.  The Max patch is also available, for those that want to look at what is going on.

I am working on a paper that will describe everything in more detail, but the main point can hopefully be understood by looking at some of the videos I have posted in the sonomotiongram playlist on YouTube. In its most basic form, the ImageSonifyer will work more or less like Metasynth, sonifying an image. Here is a basic example showing how an image is sonified by being “played” from left to right.

But my main idea is to use motiongrams as the source material for the sonification. Here is a sonification of the high-speed guitar recordings I have written about earlier, first played at a rate of 10 seconds:

and then played at a rate of 1 second, which is about the original recording speed.

Record videos of sonification

I got a question the other day about how it is possible to record a sonifyed video file based on my sonification module for Jamoma for Max. I wrote about my first experiments with the sonifyer module here, and also published a paper at this year’s ACHI conference about the technique.

It is quite straightforward to record a video file with the original video + audio using the jit.vcr object in Max. Below is a screenshot from a patch (sonifyer-recorder.maxpat) doing this:

The most important part here is to remember to input a 4 plane matrix to jit.vcr, otherwise it will complain. For this I use the little jcom.luma2rgb% component, which will automagically convert the video stream from 1 to 4 matrices, if needed. Here I have also combined the original video, motion image as well as motiongram into one image that I record, alongside the sonification of the motion. The output from this patch looks something like this:

Sonification of motiongrams

A couple of days ago I presented the paper “Motion-sound Interaction Using Sonification based on Motiongrams” at the ACHI 2012 conference in Valencia, Spain. The paper is actually based on a Jamoma module that I developed more than a year ago, but due to other activities it took a while before I managed to write it up as a paper.

See below for the full paper and video examples.

The Paper

Abstract: The paper presents a method for sonification of human body motion based on motiongrams. Motiongrams show the spatiotemporal development of body motion by plotting average matrices of motion images over time. The resultant visual representation resembles spectrograms, and is treated as such by the new sonifyer module for Jamoma for Max, which turns motiongrams into sound by reading a part of the matrix and passing it on to an oscillator bank. The method is surprisingly simple, and has proven to be useful for analytical applications and in interactive music systems.

Full reference: A. R. Jensenius. Motion-sound interaction using sonification based on motiongrams. In ACHI 2012: The Fifth International Conference on Advances in Computer-Human Interactions, pages 170–175. IARIA, 2012.

@inproceedings{Jensenius:2012d,
    Author = {Jensenius, Alexander Refsum},
    Booktitle = {ACHI 2012: The Fifth International Conference on Advances in Computer-Human Interactions},
    Pages = {170--175},
    Publisher = {IARIA},
    Title = {Motion-sound Interaction Using Sonification based on Motiongrams},
    Year = {2012}}

Video examples

Video 1: A screencast demonstrating the jmod.sonifyer~ module.

Video 2: Examples of sonification of some basic movement patterns: up-down, sideways, diagonal and circular.

Video 3: One attempt at sonifying the two axes at the same time. Here both horizontal and vertical motiongrams are created from the same video recording, and the sonifications of the two motiongrams have been mapped to the left and right audio channel respectively.

Video 4: Examples of the importance of filtering and thresholding of the motion image for the final sounding result. The recordings were done at high-speed (200 fps) and played back at 25 fps.

Video 5: Sonification of a short violin improvisation (courtesy of Victoria Johnson).

Video 6: Sonification of a piece by a French-Canadian fiddler (courtesy of Erwin Schoonderwaldt).

Video 7: Sonification of free dance to music.

Video 8: Soniperforma: Performing with the sonifyer at Biermannsgården in Oslo on 18 December 2010. The performance was improvised and based on applying only video effects to change the sonic quality.