:-(
A former member
I'm not saying it's the case either way but...
Consider the amount of data needed to send the subititles as text versus the amount of data needed to send them as bitmap images. I'd go for the former.
However... http://216.239.51.104/search?q=cache:mk4DaCQOAcUJ:lib.hut.fi/Diss/2002/isbn9512261723/article6.pdf+digital+television+subtitles&hl=en&ie=UTF-8 has more information!
Consider the amount of data needed to send the subititles as text versus the amount of data needed to send them as bitmap images. I'd go for the former.
However... http://216.239.51.104/search?q=cache:mk4DaCQOAcUJ:lib.hut.fi/Diss/2002/isbn9512261723/article6.pdf+digital+television+subtitles&hl=en&ie=UTF-8 has more information!