Re: [ecasound] "-ev" vs. ecasignalview

New Message Reply About this list Date view Thread view Subject view Author view Other groups

Subject: Re: [ecasound] "-ev" vs. ecasignalview
From: Kai Vehmanen (
Date: Fri Oct 25 2002 - 12:39:32 EEST

On 24 Oct 2002, Adam Linson wrote:

> hi, thanks for the speedy reply. since your answer, i've installed
> 2.2.0-pre3 and gave your scenario a try. of course, i realize it's a new
> feature, so i'm not complaining(!), just asking, in case i'm doing
> something wrong. basically, the "-evp" worked perfectly, exactly as
> you've described it below, but with "-ev" i get (on RedHat 7.2):
> Exception! [mv]waddstr() returned ERR

Yup, ecamonitor can't handle if there's more info than fits
to one screen. -ev produces many lines of output, so ecamonitor
can't handle it. This should be quite easy to fix. Ecamonitor is actually
just a bit over 100 lines of python code (including all network, parsing,
curses code ;)), so it's more of a demo prototype for the NetECI concept
than a ready tool.

But I think the concept is good. Once the protocol-spec is frozen,
it shouldn't be a big task to write a really usable version of ecamonitor.
And nothing stops from writing more status apps for NetECI.

> on a related note, are there any plans for frequency-measurement tools
> in the same vein as the amplitude measurement ones (like ev/evp)? if
> not, then how may i suggest this? it could be useful, for example, in
> manipulating extreme hi's and low's (to save listeners or equipment!).

Not at the moment, but there's this awesome JACK app:

... that you can use with ecasound. You just output audio data
to a JACK port from ecasound and then you can use freqtweak to both
analyse and modify the frequency spectrum. You can route the audio back to
ecasound, to some other app, or to the soundcard.

Generally speaking, as many of you know, I'm an active member of the
linux-audio-dev community and have been for many years. I've been
personally involved in both LADSPA and JACK projects. What this
means in practise is that instead of extending ecasound in these areas,
I prefer to make sure ecasound has excellent support LADSPA, JACK
and other community-wide standards. This has worked well for effects
(there's no way any single project could develop as many good plugins
as has been developed for LADSPA). This same thing might be
happening with JACK. Another good example is Meterbridge:

... this doesn't totally replace things like "-ev" and "-evp", but
nicely extends the scope of things you can do with ecasound.

Btw; but also, although I like to support these standards, I also
     don't want to make ecasound dependent on any external,
     especially not any bleeding-edge, package.

> and on an unrelated note, i am writing some code for event-based
> "triggers", since it is my understanding that there is nothing like this
> built into ecasound. please correct me if i am wrong about this.

Hmm, what kinds of triggers (ie. what triggers what :))?

> as for a guess to what eca stands for, all i could come up with before i
> asked was either "Ephedrine-Caffeine-Aspirin" (sounds like a potential

This might bring the "War on drugs" on us,

> programming recipe), "Electronics Corporation of America" (they did make

this a lawsuit,

> tube radios), or "Evangelical Christian Association" (highly unlikely).

and this an atheist counter-attack, so I guess we better just stick to
plain 'eca'. :D

 Audio software for Linux!

New Message Reply About this list Date view Thread view Subject view Author view Other groups

This archive was generated by hypermail 2b28 : Fri Oct 25 2002 - 12:37:40 EEST