audio_codec_con -ct aac_enc -br 128 -aac_o MP4 -aac_p AAC_LC -aac_s lr -aac_ns 0 Sample.wav Sample.m4a
Now the problem happens when I try to play the file in iTunes or QuickTime. QuickTime outputs no sound and iTunes plays the file but with lots of audible static.
Other software like Winamp and Windows Media Player are able to playback the file correctly. AAC files encoded by iTunes or Nero Digital Audio+ command line tool playback fine on all software as well including iTunes and QuickTime player.
So the question is whether anyone is aware of a discrepancy in either the UMC::AACEncoder or in the apple Quicktime decoder with respect to the AAC format specification that could explain why Apple software cannot playback the files I generated using UMC?
Thanks.Link Copied
Hello,
there is ISO spec for MP4 container which I believe IPP AAC muxer do support. If you find it is not a case please submit your issue report through Intel Premier Support
Regards,
Vladimir
Hello,
I have linked the aac_enc.lib and mp3_enc.lib to audio_codec_con, but when I run it theaudio_codec_con complains codec not found like below:
intel/ipp/5.3.1.062/ipp-samples/audio-video-codecs
/_bin/linuxem64t_gcc3> ./audio_codec_con -ct aac_enc -aac_p AAC_LC -br 64 test.wav test.adts
The codec 'aac_enc'is not found.
/intel/ipp/5.3.1.062/ipp-samples/audio-video-codecs
/_bin/linuxem64t_gcc3> ./audio_codec_con -ct mp3_enc test.wav test.mp3
The codec 'mp3_enc'is not found.
How do I fix it? THanks.
Just to keep everyone on sync with that: IPP audio_codec_con sample relies on shared libraries for codecs, so appropriate shared libraries should be available at run time.
Vladimir
Hello!
Concerning playback on Apple software. It's a known bug which will be fixed in ver.6.0.
The problem is in MP4Muxer. It sets one wrong bit which is responsible for frame length. Some decoders ignore it and play such streams without problem. Even iPod nano plays it OK. But iTune and QuickTime use it. It seems that they support both 960 and 1024 frame length.
Regards
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