[MPlayer-users] Re: How to play the raw mpeg4 bitstream (ES)

[swchen]

> [Automatic answer: RTFM (read DOCS, FAQ), also read DOCS/bugreports.html]
> swchen wrote:
> >    I have got a stream encoded with ffmpeg, with file name .m4v,
> > i can sure it is a raw bitstream without any avi header
> > i can decode it using ffmpeg, but how to play it using Mplayer??
> >
> > ./mplayer movie.m4v
> > ========= sorry, this file format is not recognized/supported ====
> >
> > but i can sure it can be understood by libavcodec, how to solve this
> > problem??
>
> It may be understood by libavformat, but AFAIK, libavcodec does encoding
> and decoding of video and audio at the frame or sample level; it doesn't
> know about stream formats. MPlayer doesn't use libavformat, since it has
> its own demuxers.

thank you, i am also sure ffmpeg use libavformat to find the correct codec
to decode it.

Is is possible for Mplayer to support MPEG4-ES decoding, as i know,
mpeg4 is the same mpeg1/mpeg2 bitstream, they don't need globe header,
we can decode mpeg1/2 bitstream start from anywhere in the bitstream, it
will search
next frame start code and start to decode it.

Why Mplayer can play a MPEG2 elementary stream, but can't play a MPEG4
elementary stream?? If at this time, Mplayer can't decode a MPEG4-ES, we can
submit
patches to it. But i must know is it true first??


>  You should be able to use ffmpeg itself to put the
> video in the m4v into an AVI. Then, MPlayer can read it.
>
> Jonathan Rogers

and if i use ffmpeg to convert the mpeg4-ES into avi, ffmpeg will decode it
first then
encode it again with avi header .
(command:--> ffmpeg -i movie.m4v movie.avi) of course, this command works
fine.
But it is waste time and video quallity will be degraded!

someone tell me to use
---> ffmpeg -i movie.m4v -vcodec copy movie.avi
but using this command, it can't played correctly using mplayer, even ffmpeg
itself can't
decode the copyed movie.avi correclty.  It's strange!! I think the avi
header and because
chunk length is fixed to 2048.

I have asked this in ffmpeg, but it seems no one answer.
other command usage ??

swchen