[Speex-dev] having trouble building on Mac OS X 10.5

Erik de Castro Lopo mle+la at mega-nerd.com
Fri Feb 27 23:57:29 PST 2009


Stephen Bannasch wrote:

> I have a collection of audio speech mp3s and I wanted to try 
> converting them to speex to see if I could get smaller sizes and 
> reasonable quality.

It is always a bad idea to convert audio from one lossy compressed
format to another. Every time you compress audio with a lossy
compressor (mp3 and speex are both lossy), you lose audio quality.
That quality can never be regained.

If you uncompress the mp3 and then compress that with speex, the
speex file will always be of poorer quality than the mp3 because
you have all the mp3 artifacts and all the speex artifacts.

However, if you start with an original un-compressed source 
speech file and then compress it with mp3 and speex, speex may
well give you  better quality than mp3. 

Erik
-- 
-----------------------------------------------------------------
Erik de Castro Lopo
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"I believe C++ instills fear in programmers, fear that the
interaction of some details causes unpredictable results. Its
unmanageable complexity has spawned more fear-preventing tools
than any other language, but the solution _should_ have been
to create and use a language that does not overload the
whole goddamn human brain with irrelevant details."
-- Erik Naggum


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