[FFmpeg-devel] [PATCH] mpeg12enc: Use Closed Captions if available

[Gyan]

On 08-02-2019 01:39 AM, Carl Eugen Hoyos wrote:
> 2019-02-07 21:07 GMT+01:00, Gyan <ffmpeg at gyani.pro>:
>>
>> On 08-02-2019 01:18 AM, Carl Eugen Hoyos wrote:
>>> 2019-02-07 20:16 GMT+01:00, Mathieu Duponchelle <mathieu at centricular.com>:
>>>> ---
>>>>    doc/encoders.texi      |  3 +++
>>>>    libavcodec/mpeg12enc.c | 31 +++++++++++++++++++++++++++++++
>>>>    libavcodec/mpegvideo.h |  2 ++
>>>>    3 files changed, 36 insertions(+)
>>>>
>>>> diff --git a/doc/encoders.texi b/doc/encoders.texi
>>>> index e86ae69cc5..378a2ca8eb 100644
>>>> --- a/doc/encoders.texi
>>>> +++ b/doc/encoders.texi
>>>> @@ -2574,6 +2574,9 @@ Specifies the video_format written into the
>>>> sequence
>>>> display extension
>>>>    indicating the source of the video pictures. The default is
>>>> @samp{unspecified},
>>>>    can be @samp{component}, @samp{pal}, @samp{ntsc}, @samp{secam} or
>>>> @samp{mac}.
>>>>    For maximum compatibility, use @samp{component}.
>>>> + at item a53cc @var{boolean}
>>>> +Import closed captions (which must be ATSC compatible format) into
>>>> output.
>>>> +Only the mpeg2 and h264 decoders provide these.
>>> Sorry for the late comment:
>>> This is not a helpful sentence imo, many features are not provided
>>> by all parts of FFmpeg and it is (too) difficult to keep such lists
>>> up-to-date.
>>> Which other decoder are you thinking about?
>>>
>> Let it remain. It is informative
> How is it informative?
> Which other decoders are you thinking about?

I don't see other h264 decoders, as used within ffmpeg, exporting CC 
side-data, e.g. OpenH264 or QSV.

(I do see native hevc doing so, as well as the Decklink indev , but not 
mentioned here.)

Full coverage is difficult, but that shouldn't be used as a reason to 
suppress any coverage.

Gyan