US Patent 9317486 Synchronizing playback of digital content with captured physical content

A computing device may provide a visual cue to items of content (for example, words in a book) synchronized with the playback of companion content (for example, audio content corresponding to the book). Embodiments of the present disclosure are directed to a content playback synchronization system for use with physical books (or other physical media). In an embodiment, the computing device captures images of the physical book and may display a visual cue (for example, an underline, box, dot, cursor, or the like) to identify a current location in textual content of the captured and displayed images of the physical book corresponding to a current output position of companion audio content. As the audio content is presented (i.e., as it “plays back”), the highlight and/or visual cue may be advanced to maintain synchronization between the output position within the audio content and a corresponding position in the displayed physical textual content.