Visual music has a history of more than 100 years and was defined by Roger Fry in 1912 as a translation of music into painting. It also refers to converting sound or music into visual language like films, computer graphics or video. The reverse is also possible or to convert visual forms into sound or music.
Visual music has also been defined as a visually created composition that can have sound or not. Fine arts have defined it as intermedia. A more profound definition of the genre can be seen here or here.