If you’ve ever tried to grab captions from a streaming service like HBO Max, Paramount+, or even some corporate video platforms, you’ve likely run into a file format that isn’t .srt or .vtt . Instead, you saw .xml or .ttml . Welcome to the world of Timed Text Markup Language (TTML)—a powerful, verbose, and often misunderstood standard.
print(f"Converted {len(cues)} cues.") download_ttml("https://example.com/closedcaptions.ttml")
import glob from lxml import etree combined = etree.Element("tt", nsmap={None: "http://www.w3.org/ns/ttml"}) body = etree.SubElement(combined, "body") div = etree.SubElement(body, "div") ttml download
But respect the source. Don’t hammer APIs. And always test your converted output—TTML’s richness is both its strength and its curse.
if not convert_to_srt: return
import requests from lxml import etree def download_ttml(url, headers=None, convert_to_srt=True): resp = requests.get(url, headers=headers) resp.raise_for_status()
yt-dlp --write-subs --sub-format ttml https://example.com/video This downloads TTML if available. Use --list-subs first to check. Larger platforms serve TTML via JSON APIs. Example from a corporate LMS: If you’ve ever tried to grab captions from
ffmpeg -i input.ttml output.vtt If you have seg_1.ttml , seg_2.ttml , etc.: