[FFmpeg-user] Closed Captions for zone 1 DVD

[Carl Eugen Hoyos]

Am Di., 5. Mai 2020 um 17:41 Uhr schrieb PPRJ01 <pprj01 at orange.fr>:

> I don't understand why neither ffmpeg nor ffprobe detect presence of closed captions within MP4/H.264 in some video streams when VLC does.
>
> Let me explain this... In the past 20 years, I have been working in several countries over the world and I bought official DVDs. Not duplicates ;-) I ripped them first to VOB and recently converted them to MP4/H.264 with ffmpeg without using the "-a53cc" option.
>
> Reminder : when running ffmpeg and ffprobe, a few lines are written first to stderr. The words "Closed Captions", when present, indicate that the video stream contains closed captions.
>
> ==> The point is that ffmpeg/ffprobe do not show closed captions existence for MP4/H.264 files that come from ZONE 1 DVDs but VLC does and displays them.
>
> ==> Conversely, for zone 2 DVD, ffmpeg/ffprobe work properly.
>
> ==> Do you know why this happens ???
>
> I am currently using a Windows 10 version of ffmpeg/ffprobe. Please see the details below with a DVD, bought in zone 1, that contains closed captions.

> ________________________________________
>
> ffprobe version 4.1 Copyright (c) 2007-2018 the FFmpeg developers

Please test current FFmpeg git head before reporting issues on this
mailing list.

For future questions: Please understand that your subject is maximally
misleading, please try to improve...

Finally: Please confirm that this happens for files where the first closed
captions appear later in the stream and retry with (very) large values
for -analyzeduration and -probesize.

Carl Eugen