Hi Jim,
A nice demo! I agree that listening to the results is going to be the best
option for measuring the bit sensitivities. But if there's lots of bits,
over different samples, perhaps tested with different channel codes, then
that's a lot of listening!
So it might be interesting to test a quantitative measure of the effect of
different bit errors and see how that compares to the subjective test.
Spectral distance measures can be used in this situation eg see
http://en.wikipedia.org/wiki/Log-spectral_distance The aim would be to
measure the average distortion, in terms of power spectral differences,
over time periods that match the variations in typical speech. Errors could
be introduced randomly and used to rank bit sensitivities, for a given BER.
There's various code around eg
http://www.mathworks.com.au/matlabcentral/fileexchange/9998-log-spectral-distance.
I've used other spectral distance measures but not this one. Not sure how
well it would work, but could be useful for coarse tuning of the error
correction ...
Cheers, Bill
On 26 October 2012 19:14, David Rowe <[email protected]> wrote:
> Hi Jimmy,
>
> Very good work .... nice to be able to hear the effect f each bit
> getting messed up.
>
> Cheers,
>
> David
>
> On Fri, 2012-10-26 at 03:58 -0400, Jimmy Carter wrote:
> > Hello again,
> >
> > I went ahead and tried to make it a little easier for others to help
> > with the subjective measurements.
> >
> > A small write-up can be found at http://kg4sgp.com/codec2-bit-study.html
> > . This page has links to audio with corresponding bit corruptions. From
> > the listening I've done there is definitely a difference in the
> > sensitivity of the different bit types.
> >
> > Please excuse the simple site. As you can probably tell it's not a
> > priority of mine.
> >
> > KG4SGP - Jim
> >
>
------------------------------------------------------------------------------
Everyone hates slow websites. So do we.
Make your web apps faster with AppDynamics
Download AppDynamics Lite for free today:
http://p.sf.net/sfu/appdyn_sfd2d_oct
_______________________________________________
Freetel-codec2 mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/freetel-codec2
