[FFmpeg-devel] [PATCH v5 1/4] avformat/rcwtdec: add RCWT Closed Captions demuxer

[Stefano Sabatini]

On date Tuesday 2024-03-19 12:39:10 -0500, Marth64 wrote:
> Signed-off-by: Marth64 <marth64 at proxyid.net>
> ---
>  Changelog                |   2 +-
>  doc/demuxers.texi        |  29 ++++++++
>  libavformat/Makefile     |   1 +
>  libavformat/allformats.c |   1 +
>  libavformat/rcwtdec.c    | 148 +++++++++++++++++++++++++++++++++++++++
>  5 files changed, 180 insertions(+), 1 deletion(-)
>  create mode 100644 libavformat/rcwtdec.c
> 
> diff --git a/Changelog b/Changelog
> index e3ca52430c..be871f75cd 100644
> --- a/Changelog
> +++ b/Changelog
> @@ -19,7 +19,7 @@ version <next>:
>  - lavu/eval: introduce randomi() function in expressions
>  - VVC decoder
>  - fsync filter
> -- Raw Captions with Time (RCWT) closed caption muxer
> +- Raw Captions with Time (RCWT) closed caption muxer and demuxer
>  - ffmpeg CLI -bsf option may now be used for input as well as output
>  - ffmpeg CLI options may now be used as -/opt <path>, which is equivalent
>    to -opt <contents of file <path>>
> diff --git a/doc/demuxers.texi b/doc/demuxers.texi
> index b70f3a38d7..26d4ba18a1 100644
> --- a/doc/demuxers.texi
> +++ b/doc/demuxers.texi
> @@ -1038,6 +1038,35 @@ the command:
>  ffplay -f rawvideo -pixel_format rgb24 -video_size 320x240 -framerate 10 input.raw
>  @end example
>  
> + at anchor{rcwtdec}
> + at section rcwt
> +
> +RCWT (Raw Captions With Time) is a format native to ccextractor, a commonly
> +used open source tool for processing 608/708 Closed Captions (CC) sources.
> +It can be used to archive the original, raw CC bitstream and to produce
> +a source file for later CC processing or conversion. This demuxer can process
> +RCWT sources created by ccextractor or FFmpeg. For more information on the format,
> +see @ref{rcwtenc,,,ffmpeg-formats}.
> +
> +This demuxer implements the specification as of March 2024, which has
> +been stable and unchanged since April 2014.
> +
> + at subsection Examples
> +
> + at itemize
> + at item

> +Render Closed Captions to ASSA (using FFmpeg's CC decoder):

ASS ??

> + at example
> +ffmpeg -i CC.rcwt.bin CC.ass
> + at end example
> +
> + at item

> +Convert an RCWT backup to SCC:

for the sake of exclicitness, I'd avoid more acronyms, I'd guess this
is source Closed Caption?

[...]

Looks good to me otherwise, thanks.