[FFmpeg-devel] Stream with Closed caption does not set appropriate flag

anshul anshul.ffmpeg at gmail.com
Mon Mar 10 12:12:53 CET 2014

On 03/10/2014 02:28 PM, Nicolas George wrote:
> (I believe I do not have the privileges to do it, but I suggest someone adds
> it to the sample collection with a clear file name to show it contains
> CEA-708 subcc.
Its CEA-608 not 708
> Thanks for that too, of course. Per any chance, do you also have code 
> that turns the contents of that file into useful information: timing 
> and text?
here is link 
of ccextractor
The source code is very big and does not use ffmpeg at all.

For timing we can look at packet pts if you want it to do with ffmpeg.

I am interested in adding this feature myself for ffmpeg ,I would 
appreciate if you give direction rather then solving.

This issue has been disscussed already in #1778, for quick reference 
adding those comments

      Changed 17 months ago
      by reimar

The situation is not quite as simple.
The problem in this specific case is that it does not have CC data in a 
separate stream but embedded in the video frame data.
FFmpeg currently has no way of handling this mess where one stream 
(video) contains another one (subtitles/CC).
CC in e.g. wtv, mxf and even mov as in ticket #846 
<http://trac.ffmpeg.org/ticket/846> is actually supported in so far as 
extracting it is possible, we just can't decode it into plain text or 
such and we can't mux it either.

      Changed 17 months ago
      by mikecheat04

I see. Could any of the code from the libzvbi project maybe help with 
this? It seems they've found a way to gather that information from the 
video stream and then mux it into a TS. There is also another project 
called OB-Encoder, they use libav, libx264, and libzvbi with a third 
party mpegts muxer to produce the desired output. I could use their 
program but they don't currently support mpeg2 and some of the more 
advance features of ffmepg that I've accustomed to.

libzvbi - http://zapping.sourceforge.net/ZVBI/Download.html
obencoder - http://code.google.com/p/open-broadcast-encoder/downloads/list


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