In Roland Barthes ‘Photographic message’ he talks of how the structure of the photograph is not singular, but in direct correlation with the structure of text, be it captions or accompanying words. Both structures are separate from each other and only once both structures are fully understood i.e. the text and the image can the whole story be understood.
Bathes talks of how other messages cease to also have a code, such as paintings and theatre. They do however have a supplementary message, as Barthes puts it the denoted and connoted message.
In Barthes opinion all the arts have these two parts of a message with in them The denoted message is one of description, with the connoted part being that which is more difficult to interpret, the meaning of the art itself to the viewer.