1. Export a MIDI marker file from Avid Pro Tools
Under "File -> Export -> Session Info as text" you can export the markers from Pro Tools.
2. Use the "Subtitle Tool & Converter" to convert the MIDI marker file into a TTML subtitle file
Open the free Subtitle Tool & Converter, select "Avid Pro Tools > Midi Markers (.midi)" and set "convert" to "TTML". Generate and download the file. If you have problems converting the file, you can contact the free support.
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