[FFmpeg-devel] [RFC] native MMS as URLProtocol

[Björn Axelsson]

On Tue, 2007-08-28 at 10:18 -0400, Ronald S. Bultje wrote:
> Hi,
> 
> On 8/28/07, Bj?rn Axelsson <bjorn.axelsson at intinor.se> wrote:
> >
> > here's my take on modifying Ryan Martell's native_mms.c as a protocol
> > rather than as a format. In this version there's also quite a few
> > smaller changes for better server compability and code simplicity.
> >
> > It makes much more sense as a protocol, but it will also require
> > extensions to the URLProtocol and ByteIOContext APIs with play, pause
> > and time-seek functionality (the same functionality as read_play,
> > read_pause and read_seek in AVInputFormat).
>
> Not that I disagree, but doesn't it at least make sense to keep mms and rtsp
> at the same level here? Having two interfaces for the two is, well,
> disgustingly ugly for applications wanting to support both.

I agree fully. But the most abstracted interface is still through an
AVInputFormat (av_open_input_file()) for both MMS and RTSP. MMS can be
accessed transparently (well, as much as RTSP at least, considering the
pause issues) through the ASF demuxer, which is how I imagine most
applications will use it. Any av_read_play(), av_read_seek() etc calls
on the AVInputFormat are transparently forwarded to the protocol.

Having it as a protocol additionally lets MMS-aware applications cleanly
use the protocol directly without going through a demuxer. I have to
confess that making this possible is something of a secret agenda for
me, but I can't be the only one who sees the value in it.

I don't know the details of the RTSP implementation, but perhaps it is
more or less trivial to change it into a protocol too?

-- 
Bj?rn Axelsson                    Phone: +46-(0)90-18 98 97
Intinor AB                          Fax: +46-(0)920-757 10
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