Codes and Conventions of a film trailer

The codes and conventions of a film trailer consists of themes that are reflective of that film's genre. For example in an action high adrenaline film in the trailer the audience would see scenes like explosions, guns and car chases. In horror films there would be scenes such as people screaming and blood and gore etc..
Another convention of a film trailer is that a film trailer includes graphic captions such as the release date of that film, the directors name, the actors' names starring in the film and any other text that is related to that film.
Another convention of a film trailer is the use of non-diegetic sound. This is used to help reflect the type of genre a film is. Non-diegetic sound is a sound who's source that is not visible on-screen. An example of non-diegetic is the narrator's commentary above the original footage and sound effects such as soundtracks to help create different effects.
Also included within a film trailer is the production company's logo who have made the film/trailer, a couple of examples of companies are 20th Century Fox, Paramount or Warner Bros. The production company's logos are usually show at the beginning or ending of a film trailer.
Narrative Enigma is also another code and convention of a film trailer. A narrative enigma is a question that underpins a story and will or won't be answered in the conclusion of the trailer. To explain the trailer will start and end without the audience coming to a clear conclusion about the conclusion of the film.
Editing is probably one of the most important codes and conventions of a film trailer. A film trailer depends on the edits to make the trailer as entertaining as possible, as you can put any scene in any order as long as it fits together to make the film trailer as entertaining as possible. In an action film trailer the cuts will be quick only showing very short snippets from the film itself and not revealing to much information from the film to keep the audience guessing.
The last code and convention of a film trailer is the camera shots used within the trailer. Any camera shot can be used but when in a trailer they are showing the actors who star in the film a close up shot is used to clearly show who they are.