[Speex-dev] Delays estimation in Speex algorithms

[Jean-Marc Valin]

Quoting John Ridges <jridges at masque.com>:
> I also need to know the precise delays from Speex but I used the
> SPEEX_GET_LOOKAHEAD control requests to determine them (plus the
> "speex_resampler_get_output_latency" function from the resampler). The
> returned values from the Speex lookahead request don't seem to match
> with the values you gave Alexander. Am I doing this wrong? Thanks,

What's the difference between what I wrote and what you get from Speex?

   Jean-Marc

> John Ridges
>
>
> speex-dev-request at xiph.org wrote:
> >
> > Alexander Chemeris a ?crit :
> >
> >> I want to do a careful measure of mic-to-net and net-to-spkr delays
> >> in sip media engine and to make it really precise I need to know
> >> delays, introduced by Speex algorithms. In particular, I'm interested
> >> in delays of:
> >> 1) encoder in NB, WB and UWB modes,
> >>
> >
> > NB: 25 ms, WB: ~28 ms, UWB: ~30 ms
> >
> >
> >> 2) decoder (I guess it should be 0?)
> >>
> >
> > 5 ms
> >
> >
> >> 3) resampler. I think it varies depending on input rate to output rate
> >> ratio. Any generic formula or at least values for specific ratios
> available?
> >>
> >
> > The higher the quality, the higher the delay
> >
> >
> >> 4) AEC
> >>
> >
> > 0 ms
> >
> >
> >> 5) preprocessor
> >>
> >
> > 1 frame extra delay (i.e. you get back the last frame you sent the last
> > time)
> >
> > 	Jean-Marc
> >
> >
> > ------------------------------
> >
> >
> >
>
>
>