ATSC Picture User Data in Closed Captioning

Question

In Adobe Media Server 5.0.1,Closed captioning workflows supported Streaming captioning data stored in ATSC Picture User Data. What is ATSC Picture User Data?

Answer 1

MPEG2 transport streams allows user data to be inserted in the elementary stream. One type is picture user data, and that is what's used in ATSC for close captioning videos.

The relevant US/Canadian standards are EIA-608(deprecated) or CEA-708. You can read more about it on wikipedia: