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Originally posted by tiki4
@dillee1:
Just to give some minor corrections to what you poster (sorry). I'm hanging out on HA for quite a while now and follow discussions with Menno (that's his name) Bakker and Ivan Dimkovic, the guys that work for Ahead.
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Maybe it's also a good idea to hang out at the forum (and the Wiki) of Audiocoding.com now and then...
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1) aacenc.exe from RareWares (now rarewares.hydrogenaudio.org ) still produces standard compliant AAC streams as it uses an MPEG2 ADTS header, which hasn't changed.
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That's right, the problem always has been and still is with MPEG-4 software from Apple and others that is not fully standard-compliant, because it does not recognize MPEG-2 AAC LC files (and MP3 within a MP4 container and multichannel audio files etc.).
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2) aacenc_mpeg4.exe from RareWares produced MPEG4 ADTS headers which weren't standard compliant due to some recent changes. Therefore that version was removed. Also recent updates were included in the mp4tools.rar package (version 0.9.8) that is hosted on RareWares.
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Correct, if you want to know more about this, read e.g. some of the recent threads and/or the Wiki pages about MP4 and ADTS on Audiocoding.com. By the way, for Apple users there's a brand new MPEG4IP package on RareWares now with a patched version of mp4creator.
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3) For playback you are absolutely right. 3ivx + ffdshow: this is the combination that I use as well.
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Another possibility would be mplayer that also seems to work well with multichannel MP4 files when compiled with FAAD2 (see the related thread on Audiocoding.com). The 3ivx developer promised to release a new AAC decoder for their DS filter 2 days ago (not based on FAAD anymore), so multichannel audio in a MP4 file should be possible soon with 3ivx.
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4) Some minor hint: Quicktime player still refuses in version 6.1 on Windows to play MP4 files which have an AAC audio track with MPEG2 ADTS header. I still don't know of any way how to change that. Maybe someone knows how to do that (bitstream is identical).
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Well, the problem is simply this MPEG-2 flag instead of the MPEG-4 flag that QuickTime expects in the MP4 file header, so the easiest solution for PsyTEL AACEnc files is to enable mp4creator to change that flag while muxing.
Enrico Palmeri is working on that (and another closely related issue) right now and will send the necessary changes to the mp4creator code to Bill May (the MPEG4IP developer) as soon as he figures out how to implement command line switches in mp4creator. His hardcoded changes already work since several weeks now, so if someone here is willing to help, he might post on the Audiocoding.com forum perhaps. Enrico published the source code of his changes (without the command line switches) some days ago on the Apple QuickTime forum for Windows ("QT 6 not fully standard-compliant..."), so you could have a look at it there.