pysubs2 is a Python library for editing subtitle files. It’s based on SubStation Alpha, the native format of Aegisub; it also supports SubRip (SRT), MicroDVD, MPL2, TMP and WebVTT formats and OpenAI Whisper captions.

There is a small CLI tool for batch conversion and retiming.

pip install pysubs2
pysubs2 --shift 0.3s *.srt
pysubs2 --to srt *.ass

import pysubs2
subs = pysubs2.load("my_subtitles.ass", encoding="utf-8")
subs.shift(s=2.5)
for line in subs:
    line.text = "{\\be1}" + line.text
subs.save("my_subtitles_edited.ass")

To learn more, please see the documentation. If you'd like to contribute, see CONTRIBUTING.md.

pysubs2 is licensed under the MIT license (see LICENSE.txt).