Historical
CEA 608-E-2008 (ANSI)
Line 21 Data Services
Serves as a technical guide for those providing encoding equipment and/or decoding equipment to produce material with encoded data embedded in Line 21 of the vertical blanking interval of the NTSC video signal. It is also a usage guide for those who will produce material using such equipment. Revision incorporates analog content advisory, TSID, URL and other prior standards and bulletins.
Consumer Electronics Association [cea]