[imsc] tts:position should be allowed on region only

palemieux has just created a new issue for https://github.com/w3c/imsc:

== tts:position should be allowed on region only ==
To be consistent with `tts:origin`, `tts:position` should be
- allowed only on `region` only
- use px units or "percentage" only

See also https://github.com/w3c/ttml2/issues/710

Please view or discuss this issue at https://github.com/w3c/imsc/issues/366 using your GitHub account

Received on Wednesday, 4 April 2018 21:59:09 UTC