> From: Robert Hegemann <[EMAIL PROTECTED]>
> Date: Fri, 7 Jan 2000 08:27:05 +0100
>
> Mark wrote:
> > and also will use the same amount of bits for both mid and side channels!
>
> But, that's not always bad doing so.
>
> > Another quick fix: the '-m s' option :-)
>
> yes, at the cost of twice the file size :) (at least in my example)
>
> A+B.wav as VBR in stereo 95 kbits
> j-stereo 32 kbits - underwater sounding warblings
> *j-stereo 55 kbits - sounds the same as in stereo
>
> *j-stereo: is joint stereo without the side channel extra.
>
> >
> > How about this: To allocate bits between mid and side channel, go
> > back to using the ratio of mid_channel_energy / side_channel_energy?
>
> How would this work in VBR? In my example the mid channel gets 0 Bits.
> How many bits will the side channel getting? 0 * xyRatio = 0
>
It would not work in your example, but I think your example is quite
pathological! mid/side stereo is a trick suitable for the very common
case when the L & R channels are very similar.
To develop another trick for the *extremely rare* case where the L
and R channels are 180 degrees out of phase is probably not worth
the effort? In that case I think mid/side stereo should just
not be used.
Mark
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