According to the New Oxford American Dictionary, “To transcode" means "to convert (a language or information) from one form of coded representation to another". In the musical context, transcoding refers to a series of techniques that either call upon extra-musical elements, or seek a certain unity of musical content by sharing the same structure between several parameters of the musical discourse.Transcoding can also be concerned with the relationships between subfields of the same artistic expression. For example, one of the most important paradigms of modern music is the relationship between acoustics and music. The techniques of the spectral school can be seen as a desire to transcode the internal structures and properties of sound into orchestration. This relationship is even more evident today with the tools of computer-assisted orchestration, where computers mediate between acoustic model and orchestration. If in the past the links between music, alphabetic code and literature have shaped most transcoding approaches, in the contemporary period, composers are going to look in other domains for structural sources. In the case of the music made to accompany contemporary experimental movies, a transcoding approach can allow investigations associating parameters of musical composition and computer analysis of data extracted from film frames (data such as the relative percentage of black and white dots per frame, the difference between the position of the dots from one frame to another). The history of musical practices indicates that music and transcoding form an important binomial, inviting us to a deeper and more scientific look at the subject. This presentation will focus on one of the authors compositions, conceived using transcoding techniques associating music and experimental film.