Re: [codec] Planning of further codec testing

Gregory Maxwell <> Fri, 05 August 2011 15:20 UTC

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From: Gregory Maxwell <>
To: Christian Hoene <>, "" <>
Date: Fri, 5 Aug 2011 07:26:53 -0700
Thread-Topic: [codec] Planning of further codec testing
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Subject: Re: [codec] Planning of further codec testing
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Christian Hoene [] wrote:
> Does anybody know how to get an AAC-LD encoder and decoder?

I was hoping someone would provide a better answer:

There is an implementation of an AAC-LD encoder and decoder
included with Apple computers.  People with quicktime pro
installed are able to select it and write AAC-LD to mp4 files and
decode from them to wav.

As I recall the encoder's selection is some limited in terms of
supported sample/bitrates, and doesn't present pretty much
any options, I seem to recall it using the larger of the supported
frame sizes, and also having extensive bitres usage (not really
hard CBR).   "Take it or leave it". 

If you use it you will want to be careful to check to see the
the files it wrote were what you wanted and not some other

I'm also not sure if it's a particularly good implementation or
not, but it seemed to work okay.