The USB Audio/Video (AV) Device Class Definition describes the methods used to communicate with devices or functions embedded in composite devices that are used to manipulate audio, video, voice, and all image- and sound-related functionality. This includes both AV data (analog and digital) and associated metadata and the functionality that is used to directly control the AV environment, such as Volume and Contrast Controls. Examples range from cameras used for video chat and conferencing to full-fledged TV sets that can be used as displays for mobile devices. The AV Device Class does not include functionality to operate transport mechanisms that are related to the reproduction of AV data, such as tape transport mechanisms or CD-ROM drive control. Handling of MIDI data streams over the USB is directly related to audio but will not be covered in this version of the specification. Future versions may include support for MIDI.
Device Class Specification