Release 1.2.3 Release Candidate 1 · sandflow/ttconv

Release planned for 2026-08-28.

What's Changed

Fix SCC NDF timecode drift: parse at FPS_29_97, fix add_frames() DF flag by @powelli in #506
Error on zero ttp:cellResolution components by @palemieux in #520
Raise an error on negative tts:lineHeight by @palemieux in #519
Log an error when parsing an empty tts:position by @palemieux in #522
Improve parse_color() error reporting by @palemieux in #521
Improve time expression parsing by @palemieux in #523
Fix style inheritance in VTT and SRT writers by @palemieux in #518
IMSC reader: accept all(...) syntax in ttp:contentProfiles by @Sanjays2402 in #524
imsc_reader: remove the spurious requirement that style element must have an id by @palemieux in #529
imsc_reader: ignore style elements with no id for referential styling resolution by @palemieux in #531
model: allow empty ruby element by @palemieux in #533
srt_reader: handle unbalanced and mismatched tags by @palemieux in #539
srt_reader: handle empty cues by @palemieux in #541
SRT Writer: add a unit test for LWSP-only lines by @palemieux and @youdie006 in #543
VTT Reader: handle WebVTT files with bad signatures by @palemieux and @eeshsaxena in #536
Remove use of dataclasses._MISSING_TYPE by @palemieux and @eamanu in #546

Full Changelog: 1.2.2...1.2.3-rc.1