A method and apparatus for authoring an architecture for transforming a single-core based embedded software application to a multi-core based embedded software application, and a method of determining an architectural pattern in a multimedia system. It is possible to perform an architecture authoring operation by using an architectural decision supporter, without prior knowledge and accumulated knowledge regarding a software architecture. Additionally, it is possible to prevent an error from occurring during authoring of an architecture, by using a concurrency-related software architectural pattern that is already evaluated. Thus, it is possible to improve overall quality of software, and to reduce a development time.