Workaround for broken(?) m4a files from ffmpeg, was Re: [PATCH] Output AAC as M4A for iTunes with metadata tags

[Simon Nash]

richard wrote:
> On Sun Apr 10 02 Simon Nash wrote:
> 
>> I would be interested in trying these on my Linn DS.
> 
> I will send you three m4a files off list of Bells on Sunday (2.8Mb each)
> downloaded with get_iplayer for you to try. The 3 files are:
> 
> Bells1_noscript.m4a
> This file does not use Jon's script. The file does not play.
> 
> Bells1_noscript_mp4creator.m4a 
> This file does not use Jon's script, but has been optimized with
> mp4creator using:
> mp4creator -optimize Bells1_noscript_mp4creator.m4a
> The file does not play.
> 
> Bells1_script.m4a 
> This file uses Jon's script. The file plays OK.
> 
> I also ran the files with AtomicParsley. The results were:
> 
> :~/audio$ AtomicParsley Bells1_noscript.m4a -t + 
> free atom space: 2056
> padding available: 2048 bytes
> user data space: 5700
> media data space: 2880808
> 
> :~/audio$ AtomicParsley Bells1_noscript_mp4creator.m4a -t +
> free atom space: 0
> padding available: 0 bytes
> user data space: 5700
> media data space: 2880808
> 
> :~/audio$ AtomicParsley Bells1_script.m4a -t +
> free atom space: 0
> padding available: 0 bytes
> user data space: 5700
> media data space: 2880808
> 
Thanks for sending these.  I tried them on the Linn DS and they all
played OK.  It seems that there is some other issue with the Marantz
that doesn't affect the Linn DS.  I'll look at the three files in
more detail to see if I can get any clues from that.

> I'd be interested to know how you managed to get a m4a file to play on
> my Marantz using only mp4creator. I cannot replicate that. It seems to
> need mp4tags to rewrite the metadata atoms to make the file playable.
> Unless you know otherwise.
>  
The test files that I sent you were actually created using iTunes and then
patched to remove the iTunes-specific header information.  I have verified
that files produced by mp4creator with the -optimize option play OK on the
Linn DS, but it seems that for some reason they don't play on the Marantz.

   Simon