the great mp4box tool from the gpac project is now able (latest cvs) to place "raw" adts he-aac streams into .mp4 with correct signalling of sbr
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Full Version: correct importing of adts he-aac to .mp4 possible
mp4box .aac adts he-aac importing has now been updated and supports three ways of signalling he-aac (as defined in the specs):
enjoy
QUOTE
* do nothing in PL and audioSpecInfo, and let decoder detect
HE-AAC in the bitstream payload ("implicit" signaling)
* backward-compatible explicit signaling: signal regular AAC
main audio object type (and audioPL in IOD), let the decoder
detect HE-AAC if present in decSpecInfo
(extensionAudioObjectType)
*- hierarchical explicit signaling: main audio object type is
AAC-SBR, and audioPL shall be an HE-AAC profile.
in mp4box, this translates to:
-sbr: backward-compatible explicit signaling
-sbrx: hierarchical explicit signaling
the "implicit signaling" as described in audio spec is the
default AAC import (without -sbr or -sbrx option)
If aac is MPEG-2, MP4Box defaults to backward-compatible
explicit signaling since there are no MPEG-2 HE-AAC PLs
defined for MPEG-4 IOD.
HE-AAC in the bitstream payload ("implicit" signaling)
* backward-compatible explicit signaling: signal regular AAC
main audio object type (and audioPL in IOD), let the decoder
detect HE-AAC if present in decSpecInfo
(extensionAudioObjectType)
*- hierarchical explicit signaling: main audio object type is
AAC-SBR, and audioPL shall be an HE-AAC profile.
in mp4box, this translates to:
-sbr: backward-compatible explicit signaling
-sbrx: hierarchical explicit signaling
the "implicit signaling" as described in audio spec is the
default AAC import (without -sbr or -sbrx option)
If aac is MPEG-2, MP4Box defaults to backward-compatible
explicit signaling since there are no MPEG-2 HE-AAC PLs
defined for MPEG-4 IOD.
enjoy
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