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I'm not sure that its proprietary and its codec independent i.e. it supports tracks encoded with h263 mp4 etc.! There's a working document from Ericsson at the 3gpp site. http://www.3gpp.org/ftp/tsg_sa/WG4_CODEC/ Tdoc S4 03 0417 which is version 0.2.0 of the 3gp file format. http://www.3gpp.org/ftp/tsg_sa/WG4_CODEC/TSGS4_26/Docs/ My understanding was that its a file format that is targeting wired/wireless media delivery. It allows for multi-tracked content and delivery using alternate groups for tracks and switch groups. You know if you use say, the mpeg4ip project and you dump an mp4 file, you get a hierarchy of various tracks and atoms. What Im interested in or rather curious about, is what is the difference in terms of atoms and meta-info between the mp4 file format and the 3gp file format! Thanks, rgds, Nikki ----- Original Message ----- From: "Richard, John" <email@hidden> To: "Nikki Cranley" <email@hidden> Sent: Tuesday, June 10, 2003 2:18 PM Subject: RE: Whats the diffrerence between 3GP and MP4 file format? 3GP is a proprietary format the nokia phones use. The video codec is 3GP specified h.263 base line. You can play H.263 video with AMR audio. I don't know much about 3GP, so I cant compare diffences. My guess would be that 3GP is only ment for low bit rate streams, and MP4 is meant for both high and low bit rate streams. It also sounds like 3GP is only one audio and video track, where MP4 can have many elements beside audio and video, such as sprites and text....MP4 is more multimedia than audio/video only. -----Original Message----- From: Nikki Cranley [mailto:email@hidden] Sent: Tuesday, June 10, 2003 8:51 AM To: email@hidden Subject: Whats the diffrerence between 3GP and MP4 file format? Hi All, I'm just wondering what the difference is between 3GP file format and the MP4 file format? Rgds, Nikki Nikki Cranley, Performance Engineering Lab, Mobile Multimedia, DCU School of Engineering, S220 UCD Dept. of Computer Science, A006 ************************************************* PEL LAB: http://www.eeng.dcu.ie/~pel/ RESEARCH: http://www.eeng.dcu.ie/~cranleyn/ ART: http://www.eeng.dcu.ie/~cranleyn/art/ ************************************************* ----- Original Message ----- From: "David-Steve DIGEON" <email@hidden> To: "John Michael Zorko" <email@hidden> Cc: <email@hidden> Sent: Tuesday, June 10, 2003 9:13 AM Subject: Re: Adding RTP Headers > Many thanks John. > > I have read the RFC1889 and I know how to build headers but what I > was asking was if there's already some methods implemented to add RTP > headers automaticaly to my payload (currently only text) not linked to > the QuickTime classes. It seems when I use a debugger that the RTP > headers are created and added before a QTSS_Write call but I can't > find where. I suppose they are linked with QT* classes those I don't > use. > > Am I right or do I miss something? > > Regards, > > David-Steve > ------------------- > > > >David-Steve ... > > > >> does anybody know where I can find support to create RTP headers? I > >> don't use QT movies, I just want to stream a text file. Currently > >> I'm able to send some packets but without RTP headers. I haven't > >> found any method that could help to build the rtp > headers. > >> > >> If someone knows where I can find support for this task, it will > help > >> me a lot. > > > >I'm a bit confused as to what you're searching for. RFC1889 > describes > >the RTP headers very well, if you want to know what they look like > and > >/ or how to make one (there is even some source code in RFC1889 for > >packet headers, if I remember correctly). Are you asking for > direction > >into the DSS code to the place where RTP headers are created? If > this > >is the case, look in Server.tproj/RTPStream.h and follow > >RTPStream::ReliableRTPWrite(), RTPStream::InterleavedWrite(). Also, > >you can look at APIModules/QTSSReflectorModule/ReflectorStream.h, > >specifically the ReflectorPacket class. > > > >I hope this helps. Let me know if I can be of further assistance. > > > >Regards, > > > >John > > > >Falling You - exploring the beauty of voice and sound > >New EP, "hope thrown down," available now at > >http://www.mp3.com/fallingyou > _______________________________________________ > streaming-server-developers mailing list | email@hidden > Help/Unsubscribe/Archives: http://www.lists.apple.com/mailman/listinfo/streaming-server-developers > Do not post admin requests to the list. They will be ignored. _______________________________________________ streaming-server-developers mailing list | email@hidden Help/Unsubscribe/Archives: http://www.lists.apple.com/mailman/listinfo/streaming-server-developers Do not post admin requests to the list. They will be ignored. _______________________________________________ streaming-server-developers mailing list | email@hidden Help/Unsubscribe/Archives: http://www.lists.apple.com/mailman/listinfo/streaming-server-developers Do not post admin requests to the list. They will be ignored.
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