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68 lines
2.8 KiB
Text
68 lines
2.8 KiB
Text
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//////////////////////////////////////////////////////////////////////////
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// //
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// INSTRUCTIONS FOR MPLEX - THE MPEG1/SYSTEMS MULTIPLEXER //
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// //
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//////////////////////////////////////////////////////////////////////////
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Please note that I do not have a comprehensive instruction manual for this
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release. I suggest you try the program out with some default values and
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learn something more about ISO/IEC 11172-1 (aka MPEG1/Systems).
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For those of you that can read *German*, you can download a postscript
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paper discussing implementation and problems of this software, with
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introductions to MPEG1/Audio, MPEG1/Video and MPEG1/Systems.
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You should find the paper with the same distribution you got this
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program from.
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If not, you should find the postscript version of this 40-page paper
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on
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ftp.informatik.tu-muenchen.de in /pub/comp/graphics/mpeg/mplex
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(121822 bytes, Jun 30 , 1994 , mpeg_systems_paper_0.99.ps.gz)
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If you have any questions you cannot figure out by running the
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program, feel free to ask me.
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--------------------------------------------------------------------------
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One more thing that might save me many emails:
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when asked about the startup packet delay, try something like
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half the video buffer size divided by your sector size. Say you
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have a 40 kByte video buffer and a 2324 Byte Sector size, then
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a startup delay of 8 sectors will work just fine.
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What does the above parameter mean?
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Normally, the Decoding/Presentation Time Stamp of the first access
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unit is set to the clock value that will happen exactly after the last
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packet containig data from this first unit arrives into the system
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target decoder. This works fine if the video/audio streams are of
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*very perfectly constant* or the packet size are *very* small
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(ideally: the size of one access unit, that would mean variable
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packet length).
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Anyway: this parameter allows you to say that the System Target
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Decoder should start decoding the first access unit after he
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gets (startup_packet_delay + size_of_first_access_units[av])
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packets of data.
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This guarantees that the buffers are conveniently filled up.
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Note that both the video stream offset and audio stream offset (ms)
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add up even more bytes to this startup delay, but you can
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tell conveniently that audio should start so many ms after video,
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for example.
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Sorry for no further doc, enjoy multiplexing A/V :)
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Christoph.
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moar@heaven.zfe.siemens.de
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+---------------------------------------+--------------------------------+
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| http://www.informatik.tu-muenchen.de/ | Christoph Moar |
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| cgi-bin/nph-gateway/hphalle6/~moar/ | Kaulbachstr.29a |
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| index.html | 80539 Munich |
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| email:moar@informatik.tu-muenchen.de | voice: ++49 - 89 - 23862874 |
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+---------------------------------------+--------------------------------+
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