Refresher Requested on MPEG4 Container and AtomicParsley

Jim web web at
Wed Jul 29 05:47:14 PDT 2015

In article <55B8B8AF.8020702 at>, Budgie
<ajebay at> wrote:

> Hi Jim, Many thanks.  I am going to try Vangelis's suggestions first
> since he has spent hours patiently helping me and see how I get on.  If
> all else fails I shall do your bail out and yes; go to flac.  Not sure
> what I will lose in fidelity through this process but hope it will be
> OK. Since age has tarnished my "golden ears" which I never claimed to
> have anyhow, we should be OK.  Hopefully will post progress in due
> course. Budge.

You should not lose any quality by converting to LPCM (wave) or flac. In
effect, this does what you do anyway to play the file.

What may lose quality is if you convert to a 'lossy' format like mp3, aac,

So going m4a -> wave (or flac) should be fine in quality terms. The main
snag is a bigger file. But one which may be easier for more renderers to

However going wave (or flac) -> m4a or mp3 may well lose some details or
alter the result.

For the same reason, in general going from one 'lossy' codec to another can
lose quality. Hence the value in normal circumstances of doing ffmpeg
recontainering with the 'copy' option. This protects the audio payload.
It's also a lot faster. ;->


Armstrong Audio
Audio Misc

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