HydrogenAudio

Lossy Audio Compression => AAC => AAC - General => Topic started by: frank8297 on 2012-12-20 16:52:16

Title: This AAC file plays in iTunes but not on iOS
Post by: frank8297 on 2012-12-20 16:52:16
There are a couple of AAC LC files (.aac, 128k) I would like to put on my iOS 6 devices (iPad, iPhone). I put them in M4A containers (.m4a) using MP4Box ('-add'), imported them into iTunes 11, and transferred them to my iPad. They play fine in iTunes, but they don't play on the iPad (screen switches to Play view and returns to Playlist view in a second).

HERE (http://home.arcor.de/frank9743/test20.m4a) is an example M4A that plays on iTunes but not on iOS.

I can convert the M4A files in iTunes to AAC and then they work on iOS, but I am afraid that this lossy to lossy conversion will impact quality. Is there anything I can try besides conversion?

Any suggestion or explanation is much appreciated.

Frank
Title: This AAC file plays in iTunes but not on iOS
Post by: nu774 on 2012-12-20 18:01:57
Looks like MPEG2 AAC inside of m4a, and AudioFileOpen() on that file fais with kAudioFileUnspecifiedError. I don't know why iTunes can play it. Try something like the following:
Code: [Select]
mp4box -raw 1 test20.m4a && mp4box -add test20_track1.aac:mpeg4 -new test20_mpeg4.m4a && del test20_track1.aac
Title: This AAC file plays in iTunes but not on iOS
Post by: frank8297 on 2012-12-20 20:07:19
Perfect, nu774 !
Title: This AAC file plays in iTunes but not on iOS
Post by: googlebot on 2013-03-26 20:50:23
Excellent info, thank you! I couldn't listen to some streamripper collections anymore on my iPad, that had exactly the same problem. The ":mpeg4" postfix saved my day!

For future reference, this is the correct Batchenc command for SomaFM rips (.aac):

Code: [Select]
"C:\Program Files (x86)\GPAC\Mp4box.exe" -tmp "c:\windows\temp" -add <infile>:mpeg4 <outfile.m4a> && del <infile>