Guides
Checking subtitle timing and display before handoff
After choosing a format, verify synchronization with the same video edit, timing interpretation and conversion losses, then test in the recipient's player.
Which format should you choose?
Choose by the role each file plays in your workflow.
- Agree on the video edit and time basis
- Compare text and presentation
- Play in the recipient's environment
Agree on the video edit and time basis
Record the video edit, subtitle language and purpose, and timeline origin. For TTML, agree on the timeBase, any frame or tick settings and supported profile. Distinguish a constant offset from drift that grows during playback; a uniform time shift may not fix both.
Compare text and presentation
Keep the original and compare cue text, start and end times, line breaks, positioning and styling after conversion. Use UTF-8 for WebVTT and check the recipient's SRT encoding support. Document TTML presentation features that the destination cannot preserve.
Play in the recipient's environment
Check the beginning, middle, end and edit boundaries, including synchronization after seeking, display duration and readable line breaks. Verify language labels, required speaker or sound descriptions, right-to-left text and fonts in the actual player.
Formats to consider
WebVTT
Good for: Delivering subtitle tracks to compatible web players
Less suitable for: Judging display compatibility from the extension alone
SRT
Good for: Exchanging simple subtitle text and timings
Less suitable for: Expecting precise positioning or styling to survive unconditionally
TTML
Good for: Exchanging timing and presentation under an agreed profile
Less suitable for: Handing off without checking timeBase or profile support
Before you export
- Keep original video and subtitles, conversion settings and change history. Check sharing scope and usage permissions.
- Playback checks do not certify translation accuracy or accessibility conformance. Review language and content separately.