ccDecoder is a Python Closed Caption Decoder/Extractor
Presented by Max Smith and

Python 2.7+ and Python 3 compatible

Public domain / Unlicense per license section below
But attribution is always appreciated where possible.

My primary goal of this project was to extract subtitles from my
Laserdisc collection (mostly simple pop-on mode). I've tried to cover
as much of the Closed Caption spec as possible, but I am limited by a
shortage of test-cases. I would love to get it working on some more
exotic captions (i.e. roll-up, XDS, ITV) but really need some sample
media to work with. If you have media that has these more exotic
captions - please drop me a line via my website (

Usage somevideofile.mpg >>
Extract subtitles in SRT format --ccformat scc somevideofile.mpg >> somevideofile.scc
Extract subtitles in SCC format --ccformat xds somevideofile.mpg >> somevideofile.txt
Extract XDS information


About 10-20x realtime on my i7 machine. Primarily limited by FFMpeg

A Few Notes

There are two scripts that make up this tool: A command line interface
(cc_decoder) and a library file (lib.cc_decode).

The library makes the assumption that a stream of images are passed to
it that have closed caption data embedded in the top. It also assumes
that the images are wrapped in a object which will provide standardized
access to it. The library has minimal dependencies, and may be useful
for an embedded project.

The command line interface has many dependencies including PIL (Pillow)
and FFmpeg. Excellent builds of FFMpeg are available at

If you use the command line tool - it's worth providing it with access
to a fast temporary area for writing data to, by default it will use
the system default temporary area, which may share space with your OS.