scope:

This standard includes mechanisms to allow a source of MPEG service, such as a cable or terrestrial set-top box, digital VCR, or DTV to utilize the MPEG decoding and display capabilities in a DTV. A method is included to allow the OSD Producer to supply bitmap graphic overlays for blending and composition in the DTV over decoded video.

This standard supports an optional baseband analog audio/video connection between an audio/video source device and the DTV. Mechanisms are provided to allow the source device to control the selection of the audio/video source for display in the DTV between an MPEG service decoded in the DTV and incoming analog audio/video supplied to it via an external input.

Nothing in this standard is intended to constrain the use of other 1394 based protocols.