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Re: [ARSCLIST] Lossy compression losing quality (was Re: [ARSCLIST] Pristine Audio and the Milllennials . . .)
Howard Friedman wrote:
Mike,
Excuse my ignorance, but regarding the following,
In this sort of discussion, I believe we'd do well to keep track of the
different meanings of "quality". There is the abstract sense in which
MP3 and other lossy compressors always lose information, as shown by the
inabiilty to reconstruct the original PCM signal from the compressed
file. In that sense, Don is correct in suggesting staying with lossless
formats if file size is unimportant. For example, if one is ripping
tracks from multiple CDs to make a compilation CD, there is no reason to
spend the time and accept the penalty in quality of using lossy compression.
by what means would one make a "lossless transfer," and what exactly is a "lossless format"?
One of my aphorisms is: Unlike stupidity, ignorance is a curable disease.
Herewith, a partial cure for your very limited ignorance.
MP3 is the best known scheme for "perceptual encoding" - compression in
which losses of the least perceptibility to the human ear are accepted.
Lossless compression in other sorts of file are well known and include
ZIP, RAR and TAR. Of course, they are of almost no value with audio
since those general compressors find little to squeeze out of audio.
Several compressors have been developed which are lossless. Using that
process to encode, then decode results in the original file at the bit
level. The one I use routinely is APE ( http://www.monkeysaudio.com/ ),
though FLAC is a more common selection. Depending on the properties of
the original file, either will compress by about a factor of two. Oddly,
the Monkey's Audio page acknowledges the existence of a Mac version but
does not link to it.
Mike
--
mrichter@xxxxxxx
http://www.mrichter.com/