Christophe Gisquet <[email protected]> writes:

> Are you sure it's not just a convenience to output the more practical,
> aligned 24bits? Like something in the bitstream actually indicating
> "shift left 4 bits", and the audio is *actually* 20 bits?

My inderstanding is that it really is 20 bit samples, shifted left to
fill 24-bits. From page 142 of the spec (close to the end of the section
on the XLL lossless extension):

  To obtain the output words, the resulting samples still need to be
  shifted left by NumEmptyLSBs places.

I haven't really digested the spec yet, but I think the least
significant bits are transmitted without compression. Which makes sense,
since they ought to be pretty close to white noise, which is
uncompressible by any lossless algorithm.

Regards,
/Niels

-- 
Niels Möller. PGP-encrypted email is preferred. Keyid C0B98E26.
Internet email is subject to wholesale government surveillance.
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