Methods and systems for identifying content in a data stream are provided. In one example, a client device receives a continuous data stream and substantially continuously performs a content identification of content in the data stream based on content patterns stored on the client device. The content patterns stored on the client device may include information associated with extracted features of a media file, or a temporally mapped collection of features describing a media file. The client device may determine whether the continuous data stream includes media content, and based on the determination, continuously perform the content identification of content in the data stream at the client device. The client device may query a server to determine an identity of content in the data stream based on receiving an instruction.