[FFmpeg-devel] [PATCH 0/2] ARIB STD-B24 caption decoding using libaribb24

Jan Ekström jeebjp at gmail.com
Sat Feb 2 15:31:34 EET 2019

A decoder wrapper for the libaribb24 library found in various
distributions and currently utilized by VLC.

Requires GPLv3 with the current most recent release, but as the
current library master is LGPLv3, any newer releases will require
only LGPLv3.

If the library is not found in your distribution, it is available at:

A test sample can be found at:

An example of how the decoded output currently looks can be found at:

I will proceed to making a FATE test as soon as I figure out the simplest
way to limit an MPEG-TS stream to some PIDs without doing full remuxing.
(I think dvblast has something like this so I might take a look at that)

The decoded subtitles might or might not have durations set, so with
ffmpeg.c `-fix_sub_duration` is required.

Regarding positioning:

I have an initial version of positioning implemented, but unfortunately
it requires multiple subtitle lines per AVSubtitle, and many applications
seem to fail at handling them, including the encoding portions of
libavformat/libavcodec (all lines end up concatenated into a single line, even
though that is 100% invalid as there is a header included).

Thus I have decided to post the first version out now, as when the ruby
blocks are not included as a distraction, single-line output seems to be
fine and readable/enjoyable.

Best regards,

Jan Ekström (2):
  add libaribb24 ARIB STD-B24 caption decoder
  lavf/mpegts: add reading of ARIB data coding descriptor

 Changelog               |   1 +
 configure               |   7 +
 doc/decoders.texi       |  25 +++
 libavcodec/Makefile     |   1 +
 libavcodec/allcodecs.c  |   1 +
 libavcodec/avcodec.h    |   4 +
 libavcodec/codec_desc.c |   9 +-
 libavcodec/libaribb24.c | 378 ++++++++++++++++++++++++++++++++++++++++
 libavcodec/profiles.c   |   6 +
 libavcodec/profiles.h   |   1 +
 libavcodec/version.h    |   2 +-
 libavformat/mpegts.c    |  47 +++++
 libavformat/version.h   |   2 +-
 13 files changed, 481 insertions(+), 3 deletions(-)
 create mode 100644 libavcodec/libaribb24.c


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