Re:I'm hearing impaired -- will this harm me? (Score 1)

Closed Captioning is encoded on just one line of VBI (Vertical Blanking Intervals, those "unused data space"(s) ) and is mandated by law to be located on Line 18. There are however other lines that typically go unused. There are some Interactive TV platforms that use this empty VBI, and they could be in trouble if this new HDTV format gets pushed through.