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Q: floating-point, losslessness from http://www.wavpack.com/technical.
Porcus
post Feb 17 2012, 17:00
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I quote:
QUOTE
I have decided to not use any floating-point arithmetic in WavPack's data path because I believe that integer operations are less susceptible to subtle chip to chip variations that could corrupt the lossless nature of the compression, the recent Pentium floating point bug being a blatant example of this.


Is this obsoleted, in the sense that Bryant has found that one can now trust floating-point arithmetic, or does it mean that even floating-point .WV files are created using fixed-point arithmetic, without any use of the processor's floating-point internals?


(Edited for clarification.)

This post has been edited by Porcus: Feb 17 2012, 17:37


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bryant
post Feb 17 2012, 19:18
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That document is very outdated, but that part is true. WavPack does not use floating-point for encoding or decoding, and that applies even to the floating-point audio support (the values are disassembled into integers first thing).

FLAC does not use floating-point for decoding either. However, it does use it for encoding but is done in such a way that variations in implementations cannot cause problems. There was a generally civil discussion of it here.
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