[vorbis-dev] A masking test program

Robert Voigt robert.voigt at gmx.de
Mon Jan 8 12:29:43 PST 2001



>How about we do all four tests at low resolution (like 6 tests across the
>whole spectrum), then compair the results to our current expectations,
>focusing in on the areas that disagree with our current knoweldge the
>most.

You mean getting 6 values, then let the software compare to what we
already have and decide where to go into detail? Otherwise I can't make sense out
of it.

We already have low resolution data for tone-tone masking, and something
worse for noise-tone masking. The purpose of this whole thing is to get
curves that don't have to be interpolated like hell to fit Vorbis's needs. That's
why I started with the resolution used in Vorbis (just to have something):
1/2 octaves for the masker frequency
1/8 octaves for the signal frequency
10 dB for the masker amplitude

>We can't expect too many people to put int 20hours of listening tests,
>but some will. It's much more reasonable to expect an hour or so out of a
>great number of people, we need to find the best way to make that hour >count.

I'd still say better 3-5 hours from less people with the resolution we
need than 1 hour from a lot of people with data that must be interpolated too
much. But let's make assumptions about where no masking can occur and see how
much we can eliminate. This could be done by someone taking the whole test
(perhaps we can eliminate something before that by looking at the Ehmer
curves, so it won't take 160 hours) and then we'll see. I would assume that if
there's no masking in one person's ears with one particular set of sounds,
there won't be in anyone else's ears.

I'm fixing some serious bugs in the code right now. Expect them to be in
CVS by the end of this week.


-- 
Sent through GMX FreeMail - http://www.gmx.net

--- >8 ----
List archives:  http://www.xiph.org/archives/
Ogg project homepage: http://www.xiph.org/ogg/
To unsubscribe from this list, send a message to 'vorbis-dev-request at xiph.org'
containing only the word 'unsubscribe' in the body.  No subject is needed.
Unsubscribe messages sent to the list will be ignored/filtered.




More information about the Vorbis-dev mailing list