ipod 5g, 60gb, problems with nero aac

[francescob]

hello, i'm trying to encode some cd's for my ipod 5g 60 gb with nero digital aac encoder, because i think sound quality is awesome, but i'm having some strange problems. I'm using eac with user-defined encoder, with this command:
/c C:\path\to\neroaacenc.exe -q 0.55 which gives an average 200kbs bitrate. If i rip the cd to wavs, and the encode the wavs to mp4, i can play the files smoothly with rockbox, but if i go directly from  cd to mp4, the files are not playable, if i select the from the file browser it simply goes to the next track as if the file was not found.
Any hint on this?
thank you
francesco

[Llorean]

My first suggestion would be to compare a file encoded directly to a file encoded from a WAV and see what the differences are.

[francescob]

you mean comparing size or something else?

[Llorean]

Well about all the size will tell you is *maybe* whether the files are different. I was thinking something a little more useful, like trying to figure out whether the metadata is created the same way. I think there's a program called mp4dump (or something like that, I don't really play with that format).

[francescob]

ok thanx, i'll give that a try when i'll be back home

[Lear]

Another thing to try is to add the "-i" option (or -ignorelength, don't remember exactly what it is called). Maybe if you try to encode directly through stdin and "-i" isn't specified, the metadata gets placed at the end of the file, something Rockbox doesn't support.

[francescob]

tried the -ignorelength command, no luck. Filesize is a bit different, working file is a punch of byte smaller.. now i'm going to investigate the differences between the two

ok, there is sure a problem with the file encoded directly from cd, as running mp4dump gives this message:
mp4dump.exe version 1.4.1
ReadAtom: invalid atom size, extends outside parent atom - skipping to end of ""
 "" 1229206275 vs 4915158
MP4ERROR: MP4File::FindIntegerProperty: no such property - moov.mvhd.modificatio
nTime

while with the file encoded from wav, and running in rockbox, mp4dump gives correct output

[bk]

I've found that every AAC file I have that won't play correctly in Rockbox also will bomb out mp4dump with that error (or a similar one). Obviously there's some metadata problem but mp4dump is being less than helpful in determining what it is.

[Llorean]

Actually, MP4dump has actually told you exactly what the error is (I think), that the metadata atom has an invalid size. Which would suggest that your encoder isn't creating the metadata properly.

[francescob]

using foobar for encoding the files directly from cds, using the same command line, gives fully working mp4 files

[bk]

Actually, MP4dump has actually told you exactly what the error is (I think), that the metadata atom has an invalid size. Which would suggest that your encoder isn't creating the metadata properly.

Obviously there are errors in the metadata (that goes without saying), the problem is figuring out exactly what is wrong with the metadata and why the encoder(s) are creating the files this way.

Code: [Select]

$ mp4dump ./download/audio/75minutes_59.m4a 
mp4dump version 1.5.0.1
MP4ERROR: Atom ReadProperties: atom is too small
$

Not very helpful.

[saratoga]

Try duplicating the encoding using the command line nero encoder and see if you get the same error.  Then, once you determine which software is at fault, report the bug to the proper developer.