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The Timed Text Working Group invites implementations of TTML Profiles for Internet Media Subtitles and Captions 1.0.1 (IMSC1) Candidate Recommendation. This document specifies two profiles of [TTML1]: a text-only profile and an image-only profile. These profiles are intended to be used across subtitle and caption delivery applications worldwide, thereby simplifying interoperability, consistent rendering and conversion to other subtitling and captioning formats.
This revision of the IMSC1 adds two new features (ittp:activeArea and itts:fillLineGap) to the Recommendation dated 21 April 2016.