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Are there any docs, papers or list dwellers that can answer the following (maybe very dumb but nevertheless interesting) questions: "The MP4 file format ... design is based on the QuickTime. format from Apple Computer Inc" (from http://mpeg.telecomitalialab.com/standards/mpeg-4/mpeg-4.htm) Does that mean that a QuickTime movie is a standards-compliant MPEG-4 file if it uses only codecs from the MPEG-4 standard? If yes, then is it an invalid MPEG-4 file if it uses other media codecs such as GIF or Sorenson? What about if the movie has refs to other files (the Alias Manager is probably not in the MPEG-4 spec) or has a compressed header (is zlib in the MPEG-4 spec?)? Vice versa, is an MPEG-4 media file automatically a QuickTime movie, or are there additions (it says "based on") that aren't supported by QuickTime? Envivio's streaming MPEG-4 server is based on DSS, but their client (Real/QT plugin) does not route its data through QuickTime's RTP/reassembler - they use their own homerolled UDP connections (and a local file can't be exported since they seem to do drawing directly in DirectDraw and not by decompressing frames for QT to render). Based on the license for DSS, one could assume that the MPEG-4 streaming capabilities in DSS 4 comes partly from Envivio's work (or the other way around if Apple supplied Envivio with a prerelease DSS before it became publically available). Does an MPEG-4 file need to be hinted to be streamed or does DSS include real-time packetizers for the MPEG-4 data formats? And now for the big question: Where are the affordable MPEG-4 content creation tools? Per Bergland Carmenta AB - www.carmenta.se
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