Synesthesia, or synaesthesia, is a condition where the brain mixes up the senses. People who have synesthesia are called synesthetes. There are lots of types of synesthesia but what I will be focusing on is sound synesthesia which is hearing sounds in response to seeing motion.
The phenomenon of synesthesia has influenced and inspired numerous artists and musicians to create cross-modal works that attempt to illustrate correspondences between senses. Examples of such visual music include abstract art, color organs, experimental abstract film, and music visualizers. Digital technology now makes it possible to break down rudimentary information into discrete packets of numbers and/or electrical signals. This enables computers to automate mappings of various analogous structural characteristics from one type of media to another. This is a technique used by many modern music visualizers. In most examples of visual music, the visuals are informed by and created in response to the music. However, the majority of these works were not created in real- time. Visual music artists listened to a piece of music, then created images based on their personal interpretations and responses to the expression of the music. They had the opportunity to scrutinize the overall emotion of the music, and to mark musical events of importance such as beats, rhythms, and phrases changes. They could then reference this data in the creation of images. Non-real-time generation of visual music allows for more careful and nuanced analysis of the technical and expressive elements of the music. It also results in more carefully considered visuals. However, non-real-time visual music lacks the performance aspect of real-time visualization. The problem is that real-time digital visualizers are supplied with insufficient information to effectively inform their visuals.