[pulseaudio-discuss] Software volume: linear vs. logarithmic

[Colin Guthrie]

'Twas brillig, and Jaska Uimonen at 24/08/12 09:13 did gyre and gimble:
> I don't know if I have understood everything correctly in the
> pulseaudio volume handling, but almost all operations seem to
> boil down to pa_sw_volume_to/from_linear - function, which has
> inherent cubic mapping. So (if I got this correct) if you
> do linear fade with pa_volume_t, you get cubic mapping.

Yup. I've not looked at the code for a while, but I remember going
through the cubic code a while ago.

The comments in the file point to several posts to the lad mailing list
where Lennart discusses the possible volume representations and
ultimately decided on the cubic mapping we have now.

I vaguely remember doing something related to the cubic handling when I
implemented volume controls in phonon.

Col


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Colin Guthrie
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http://colin.guthr.ie/

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