[vorbis-dev] lossless ogg encoding with good compression rate

[Sebastian Gesemann]

On Thu, 26 Jun 2003, Lourens Veen wrote:

> There's another problem though. The difference of two signed 16-bit 
> numbers is somewhere between 32767 - (-32768) = 65535 and (-32768) 
> - 32767 = -65535. That is, you need 17 bits to specify the 
> difference in the most general case.

you don't need 17 bit for the difference.
32767 - (-32768) = 1 (in 16-bit-arithmetic)
and
32767 + 1 = -32768 (in 16-bit-arithmetic)

Though this works perfectly, it won't be optimal
for entropy coding.
Check the floor-1-specification. I _really_ like
the way, Monty stores the prediction errors of
the floor's Y-values.

However... losslesly coding a signal as a sum of
2 others (the vorbis-file and the error) isn't a
good idea and far from optimal.

bye,
Sebastian

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