[FFmpeg-devel] [PATCH] Dump info for all streams (not just those known to be in a program)
Sat Nov 10 19:30:30 CET 2007
Wolfram Gloger <wmglo at dent.med.uni-muenchen.de> writes:
>> That's code snippet isn't the problem. The problem is the default
>> case in the switch statement in the new_pes_av_stream() function.
> Well those are sane defaults: if we don't know what it is, try mpeg.
"Sane defaults" are not appropriate here. If it is not MPEG, and
nowadays this is quite likely, your defaults will be completely
> Even when just choosing "stream copy" stream parameters (including
> codec id) are later adjusted by the mpeg parser.
You apparently don't know enough about how FFmpeg works, because this
statement is plain wrong.
> And if the stream really is _not_ mpeg, the chance of this producing
> _wrong_ data, rather than producing an error, are negligble IMHO.
If it is not MPEG, you will get garbage. How is that better than not
getting anything at all?
>> >> It's not user friendly to create unplayable files.
>> > I can't see how that could happen.
>> What???? It *HAS* happened. There are lots of MPEG-TS files missing
>> PSI created by broken DVB tools.
> Oh, but these files are playable just fine.
Only by pure luck. If players hadn't implemented this stupid
guessing, those DVB apps would have been fixed years ago.
> Please be clear what you're criticising -- I thought you meant
> the danger of creating something unplayable in ffmpeg through
> wrong guesswork, which I agree would be a bad thing to do.
> Can't we settle on "be liberal in what you accept, and strict in
> what you generate"?
To a certain degree, yes. I can't imagine anyone suggesting that we
attempt to play AVI files without a header, guessing that they use
MPEG4 video and MP3 audio because that's the most common. The MPEG-TS
situation is no different.
mans at mansr.com
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