Unlike live-action films, where the dialogue is simultaneously recorded with the action, in animation it must be recorded beforehand so that the movement can be fitted to it precisely. It is an essential pre-production operation, which cannot be left until after the completion of animation. Once the soundtrack is available (either on tape or digital file), the type and character of the voice can be analyzed through the use of a synchronizer (16 mm or 35 mm) and a frame-by-frame timing guide for the animation can be made. This can be done either on the exposure chart, where there is a special column for it, or on a separate chart. In either case, it must be done in terms of frame analysis. No two dialogue performances are the same. In animation, the meaning of dialogue should be somewhat overemphasized, especially in an entertainment film.