hans-jürgen
17th May 2003, 03:27
Originally posted by hans-jürgen
By the way, the necessary changes to mp4creator for signaling MPEG-2 while extracting (and MPEG-4 while muxing) have been proposed to the MPEG4IP developer on Friday, so we'll see what comes out of that. The source code of mp4creator v0.9.8.3 has just been fixed successfully by Enrico Palmeri, so it's possible now to change the MPEG-2 flag in the header of an AAC file encoded by PsyTEL AACEnc to MPEG-4 with the new -mpeg-version command line switch while muxing the AAC file into the MP4 container. :cool:
The same switch can be used to change the flag back to MPEG-2 while extracting an AAC file from a MP4 container which is necessary for Philips Expanium owners that prefer to encode their MP4 files with QuickTime 6 Pro or iTunes 4 rather than with PsyTEL AACEnc or Nero AAC that can produce MPEG-2 AAC LC files from the start. This also means that the outdated and non-standard compliant PsyTEL AACEnc_MPEG4 is definitely not needed anymore, so the confusion around these issues should get less now. :)
The new mp4creator version will appear on RareWares soon, probably today or tomorrow. It will not be available from the CVS of the MPEG4IP project, because they don't support this solution. So keep an eye on http://rarewares.hydrogenaudio.org/ and/or this thread:
http://www.audiocoding.com/phorum/read.php?f=1&i=2897&t=2897
Here's the link to the patched version:
http://rarewares.hydrogenaudio.org/files/mp4creator60.EP.zip
Nevertheless PsyTEL AACEnc is only recommended for encoding stereo AAC files, because it suffers from the same M/S matrixing bug with multichannel files as Nero AAC in its current version. So for now you should rather use FAAC v1.16 or newer for multichannel encodings and for the future the bugfixed Nero AAC codec (either in Nero Burning ROM or the new Nero Digital) and/or FAAC.
By the way, the necessary changes to mp4creator for signaling MPEG-2 while extracting (and MPEG-4 while muxing) have been proposed to the MPEG4IP developer on Friday, so we'll see what comes out of that. The source code of mp4creator v0.9.8.3 has just been fixed successfully by Enrico Palmeri, so it's possible now to change the MPEG-2 flag in the header of an AAC file encoded by PsyTEL AACEnc to MPEG-4 with the new -mpeg-version command line switch while muxing the AAC file into the MP4 container. :cool:
The same switch can be used to change the flag back to MPEG-2 while extracting an AAC file from a MP4 container which is necessary for Philips Expanium owners that prefer to encode their MP4 files with QuickTime 6 Pro or iTunes 4 rather than with PsyTEL AACEnc or Nero AAC that can produce MPEG-2 AAC LC files from the start. This also means that the outdated and non-standard compliant PsyTEL AACEnc_MPEG4 is definitely not needed anymore, so the confusion around these issues should get less now. :)
The new mp4creator version will appear on RareWares soon, probably today or tomorrow. It will not be available from the CVS of the MPEG4IP project, because they don't support this solution. So keep an eye on http://rarewares.hydrogenaudio.org/ and/or this thread:
http://www.audiocoding.com/phorum/read.php?f=1&i=2897&t=2897
Here's the link to the patched version:
http://rarewares.hydrogenaudio.org/files/mp4creator60.EP.zip
Nevertheless PsyTEL AACEnc is only recommended for encoding stereo AAC files, because it suffers from the same M/S matrixing bug with multichannel files as Nero AAC in its current version. So for now you should rather use FAAC v1.16 or newer for multichannel encodings and for the future the bugfixed Nero AAC codec (either in Nero Burning ROM or the new Nero Digital) and/or FAAC.