Multimedia search enables information search using queries in multiple data types including text and other multimedia formats. Multimedia search can be implemented through multimodal search interfaces, i.e., interfaces that allow to submit search queries not only as textual requests, but also through other media. We can distinguish two methodologies in multimedia search:

Metadata search

Search is made using the layers in metadata which contain information of the content of a multimedia file. Metadata search is easier, faster and effective because instead of working with complex material, such as an audio, a video or an image, it searches using text. There are three processes which should be done in this method:

Query by example

In query by example, the element used to search is a multimedia content (image, audio, video). In other words, the query is a media. Often, it's used audiovisual indexing. It will be necessary to choose the criteria we are going to use for creating metadata. The process of search can be divided in three parts:

Multimedia search engine

There are two big search families, in function of the content:

Visual search engine

Inside this family we can distinguish two topics: image search and video search

Audio search engine

There are different methods of audio searching: