[FFmpeg-devel] [PATCH] avcodec: add minimal teletext subtitle decoder

Carl Eugen Hoyos ceffmpeg at gmail.com
Sun Jun 14 18:03:16 EEST 2020


Am So., 14. Juni 2020 um 16:26 Uhr schrieb Marton Balint <cus at passwd.hu>:
>
>
>
> On Sun, 14 Jun 2020, Carl Eugen Hoyos wrote:
>
> > Am So., 14. Juni 2020 um 12:05 Uhr schrieb Paul B Mahol <onemda at gmail.com>:
> >>
> >> [...] this patch should be merged.
> >
> > I still believe this is one of the most important missing
> > features
>
> Which one? As far as I remember I integrated all the features (including
> colorized ass output) to libzvbi-teletextdec, so I am curious what is the
> feature that you still miss from that.

You mean apart from the fact that this project was always about
re-inventing the wheel (like it or not)?

Since this morning, I (very seriously) wonder if you have ever used
the existing teletext decoder (and how): Both "ffplay file.ts" and
"ffmpeg -i file.ts out.mkv" do not work as expected, and even if you
know that you have to specify "-txt_format ass" the output is still
completely unusable.

I believe the external library makes sense if you want "correct"
display of the ugly original teletext subtitles as overlay (which is
a 100% valid usecase) but there is no reason whatsoever for
the need of an external library to decode the text subtitles to
something that a subtitle encoder can use, even more so if a
patch exists.

It is likely that the patch needs a little more work but I find
the fact that you are blocking it very difficult to understand,
actually a little appalling.

Carl Eugen


More information about the ffmpeg-devel mailing list