Everybody knows that a picture is worth a thousand words. But did you know that a picture can also buy you the frequencies of a thousand oscillators? Using any of several modern music applications, you can convert the data that forms a picture on the computer screen into information that will generate an audio file. In most cases, the program uses the vertical position of each pixel of the image to control frequency and one or more color (RGB) values for parameters such as amplitude and stereo position.

Note that AudioPaint are standalone applications whose only role in life is the conversion of images to sound and, perhaps, vice versa. For Audition is just one of many features. Also, many of the ideas that drive image-to-sound software stem from research by Iannis Xenakis, a Greek composer whose UPIC system was among the first to allow musicians to draw the data used to generate sounds. Xenakis used imagery in creative ways when composing both his acoustic and electronic works.

Audio-Pain let you determine whether the new partials are distributed in a linear or log fashion (linear distributes the frequencies in increments of hertz, while log uses increments of cents). AudioPaint will create a new sound by using the extracted data to control the playback parameters of samples (pitch-shifting and time-stretching, for instance). Keep in mind that in most cases, you won’t automatically get musically useful results from any random image you choose to convert, regardless of which program you’re using. I found that a bit of parameter tweaking, a fair amount of “postprocessing” (reverb, pitch-shifting, and the like), and, above all, a lot of trial and error were often needed for me to get something I could use. Also, the programs that allow you to draw gestures that will control musical parameters tend to be far more useful and, ultimately, satisfying. That’s probably no surprise given the long tradition of using graphic symbols to specify musical parameters in Western music.