pysubs2 is a Python library for editing subtitle files. It’s based on SubStation Alpha, the native format of Aegisub; it also supports SubRip, MicroDVD and MPL2 formats. 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.
pysubs2 is licensed under the MIT license (see LICENSE.txt).