[Live-devel] RTSP: is random access possible on the server side?

[egf05 at doc.ic.ac.uk]

Dear all,

I am trying to solve a problem for a while and although I read the  
documentation thought I could get some help from the users of that list.

I am trying to provide mpeg files as Video on Demand (VoD) using RTSP  
streaming, leaving to the client the ability to play pause and seek  
the video. I used live555 libraries with VLC and this works pretty  
well from the client side.

However, I would like to be able to provide more control from the  
server side: I would like to be able to start a video file at a  
specific time, for instance in the middle of the file. Is there a way  
to do this? I simply want to provide the same video file as a  
"chaptered" file (like DVDs), where clients can start the file at a  
specific time. This should be an RTSP object itself that could be  
provided through an HTTP link (rtsp://my.server/file_chapter_5, where  
file_chapter_5 is an RTSP instance created at the server level, using  
a starting time option for chapter_5). Since I want people to be able  
to rewind before the starting time, splitting the video is not an  
option for me. Therefore, from the same file, I want to create  
file_chapter_1, file_chapter_2, etc... from the same mpeg video file.  
Then the client would be able to take control of the stream, for  
example by rewinding before the starting point.

Is that possible ? Using VLC, there is a -start-time option that can  
be provided at the creation of the RTSP stream, however, this is very  
buggy and the client cannot rewind the stream. I tried to discuss this  
on the videolan mailing lists but nobody could really help me. So I  
don't know if this is a limitation from the implementation or the  
protocol itself.

I would be very glad if you could help me on this problem.
thank you very much,
Eric