Visual music, sometimes called colour music, refers to the use of musical structures in visual imagery, which can also include silent films or silent Lumia work. It also refers to methods or devices which can translate sounds or music into a related visual presentation. An expanded definition may include the translation of music to painting; this was the original definition of the term, as coined by Roger Fry in 1912 to describe the work of Wassily Kandinsky. There are a variety of definitions of visual music, particularly as the field continues to expand. In some recent writing, usually in the fine art world, visual music is often confused with or defined as synaesthesia, though historically this has never been a definition of visual music. Visual music has also been defined as a form of intermedia.
Visual music also refers to systems which convert music or sound directly into visual forms, such as film, video, computer graphics, installations or performances by means of a mechanical instrument, an artist's interpretation, or a computer. The reverse is applicable also, literally converting images to sound by drawn objects and figures on a film's soundtrack, in a technique known as drawn or graphical sound. Famous visual music artists include Jordan Belson, Oskar Fischinger, Norman McLaren, John Whitney Sr., and Thomas Wilfred, plus a number contemporary artists.
Since ancient times artists have longed to create with moving lights a music for the eye comparable to the effects of sound for the ear.
– Dr. William Moritz, the best-known historian of visual music writing in English, his speciality being the work of Oskar Fischinger.
Sometimes also called "color music", the history of this tradition includes many experiments with color organs. Artist or inventors "built instruments, usually called 'color organs,' that would display modulated colored light in some kind of fluid fashion comparable to music". For example, the Farblichtspiele ('coloured-light-plays') of former Bauhaus student Ludwig Hirschfeld Mack. Several different definitions of color music exist; one is that color music is generally formless projections of colored light. Some scholars and writers have used the term color music interchangeably with visual music.
The construction of instruments to perform visual music live, as with sonic music, has been a continuous concern of this art. Color organs, while related, form an earlier tradition extending as early as the eighteenth century with the Jesuit Louis Bertrand Castel building an ocular harpsichord in the 1730s (visited by Georg Philipp Telemann, who composed for it). Other prominent color organ artist-inventors include: Alexander Wallace Rimington, Bainbridge Bishop, Thomas Wilfred, Charles Dockum, Mary Hallock-Greenewalt and Kurt Laurenz Theinert.
Visual music and abstract film or video often coincide. Some of the earliest known films of these two genres were hand-painted works produced by the Futurists Bruno Corra and Arnaldo Ginna between 1911 and 1912 (as they report in the Futurist Manifesto of Cinema), which are now lost. Mary Hallock-Greenewalt produced several reels of hand-painted films (although not traditional motion pictures) that are held by the Historical Society of Philadelphia. Like the Futurist films, and many other visual music films, her 'films' were meant to be a visualization of musical form.
Notable visual music filmmakers include: Walter Ruttmann, Hans Richter, Viking Eggeling, Oskar Fischinger, Len Lye, Jordan Belson, Norman McLaren, Mary Ellen Bute (who made a series of films she called Seeing Sound films), Harry Smith, Hy Hirsh, John and James Whitney, Steven Woloshen and many others up to present day.
In 2005, a US exhibition called "Visual Music" at the Los Angeles Museum of Contemporary Art and The Hirshhorn Museum and Sculpture Garden in Washington DC included documentation of color organs and featured many visual music films and videos as well as paintings and some color organs.
The Center for Visual Music  in Los Angeles has the world's largest collection of visual music resources. CVM owns the papers, films and much animation artwork of Oskar Fischinger; the original research collection of visual music historian Dr. William Moritz; numerous restored films by Jordan Belson; and an extensive collection of restored films by Mary Ellen Bute, John and James Whitney, Jules Engel, Charles Dockum and others. CVM consulted for and provided films, stills and research for the above-mentioned blockbuster Visual Music exhibition; CVM now provides visual music films, programs, events and talks to museums, archives, festivals and cultural centres worldwide, in addition to curating and developing its own museum exhibitions (recently, Oskar Fischinger: Experiments in Cinematic Abstraction, in Amsterdam). The Fischinger three-projector reconstruction, Raumlichtkunst, was restored and curated by CVM, and has been exhibited at the Whitney Museum NY, Tate Modern London, Len Lye Centre New Zealand, and other museums and galleries worldwide. CVM recently released the second Oskar Fischinger DVD, as well as a compilation Visual Music from CVM Archive DVD with films by Jordan Belson, Bute, Dockum, Engel and Barry Spinello. A summer 2018 CVM Visual Music symposium in California is being organized.
Artist Larry Cuba, founded the iota Fund in 1994, which was later called iotaCenter. They currently own the films of such artists as Sara Petty, Adam Beckett, some of the films of Jules Engel, Sky David, Robert Darroll and others. They hosted the renowned Kinetica programs (1999-2003) touring the world introducing new audiences to the wonders of visual music.
The cathode ray tube made possible the oscilloscope, an early electronic device that can produce images that are easily associated with sounds from microphones. The modern Laser lighting display displays wave patterns produced by similar circuitry. The imagery used to represent audio in digital audio workstations is largely based on familiar oscilloscope patterns.
The Animusic company (originally called 'Visual Music') has repeatedly demonstrated the use of computers to convert music — principally pop-rock based and composed as MIDI events — to animations. Graphic artist-designed virtual instruments which either play themselves or are played by virtual objects are all, along with the sounds, controlled by MIDI instructions.
In the image-to-sound sphere, MetaSynth includes a feature which converts images to sounds. The tool uses drawn or imported bitmap images, which can be manipulated with graphic tools, to generate new sounds or process existing audio. A reverse function allows the creation of images from sounds.
Some media player software generates animated imagery or music visualization based on a piece of recorded music:
With the increasing popularity of head mounted displays for virtual reality  there is an emerging new platform for visual music. While some developers have been focused on the impact of virtual reality on live music  or on the possibilities for music videos, virtual reality is also an emerging field for music visualization and visual music.
Many composers have applied graphic notation to write compositions. Pioneering examples are the graphical scores of John Cage and Morton Feldman. Also known is the graphical score of György Ligetis Artikulation designed by Rainer Wehinger.
Musical theorists such as Harry Partch, Erv Wilson, Ivor Darreg, Glenn Branca, and Yuri Landman applied geometry in detailed visual musical diagrams explaining microtonal structures and musical scales.