[FFmpeg-devel] Stream with Closed caption does not set appropriate flag
anshul.ffmpeg at gmail.com
Sun Mar 9 05:38:59 CET 2014
"Reimar Döffinger" <Reimar.Doeffinger at gmx.de> wrote:
>On 09.03.2014, at 00:18, Nicolas George <george at nsup.org> wrote:
>> Le sextidi 16 ventôse, an CCXXII, Reimar Döffinger a écrit :
>>> Because we cannot currently extract it, and in general extracting CC
>>> data as a separate stream is problematic since it is designed to be
>>> reordered by the video decoder along with the image.
>>> It's of course solvable but a bit of an effort.
>> It was discussed during the last VDD: if the extraction is done by
>> decoder and the resulting captions attached to the frame as meta- or
>> side-data, then the reordering is automatically done by the video
Its even implement by Michael for mpeg1-2 and h263, I am able to extract the cc using frame- side database
>But that doesn't help any with the problem here: we have no way to
>signal that a subtitle track is available from the demuxer, nor any of
>its parameters, or?
>> Of course, that does not fit well in the protocol/demuxer/decoder
>> model, but it is better than nothing, and I can see ways of making it
>> actually useful for common tasks.
>Better than nothing, sure. It's still crap, and it does not just "not
>fit well", but rather "it's barely usable". Can you even use it at all
>from command-line ffmpeg? ffplay? How about VDPAU (I guess it should
>still work, but not sure anyone tested)?
What is vdpau?
Just now ffprobe does not parse enough frames,
but if I am able to parse more info, then we can add some flag at AvStream structure.
showing that there is closed_caption inside that video stream.
My question is that, do we have any problem if we increase number of packets read at time av_find_ stream info?
Sent from my Android device with K-9 Mail. Please excuse my brevity.
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