[ecasound] Re: [linux-audio-user] 24 bit replacement for SOX

Eric Dantan Rzewnicki rzewnickie at rfa.org
Tue Dec 21 14:26:29 EST 2004

On Tue, Dec 21, 2004 at 08:27:17PM +0200, Kai Vehmanen wrote:
> On Tue, 21 Dec 2004, Eric Dantan Rzewnicki wrote:
> >> thank you for pointing this out to me -- this was indeed causing problems.
> >> If anyone wants to help in testing, please try the snapshot at:
> >> http://ecasound.seul.org/download/snapshots/ecasound-2.3.6-cvs-20041221.tar.gz
> > Will this also affect the -ei pitch shifter effect?
> Yes, if enabled at build time, libsamplerate is always used by the '-ei' 
> pitchshifter. I've not received any bugreports, but if you've 
> encountered audioble clicks in -ei output, the 20041221 snapshot should 
> fix these problems, too.

Great. Thanks Kai. I had some sort of issue with -ei being limitted to
less than the full 256 times shift supported by libsamplerate. I found
the limit somewhere in ecasound code (or was this inside libsamplerate
itself? <scratches_head> ) and changed it in my copy. Sorry to be so
vague. There was a comment somewhere in there about the shift being
limitted due to glitches in the output when extreme values were used.
Raising the limit accomplished my goals, but I do recall getting some
lack of smoothness in the results.  

I haven't updated any audio stuff on my audiobox in several months and
I'm at work at the moment. So, I'm not exactly sure what versions of 
everything i'm currently using. I've been preoccupied with building a
studio space in my basement for the past month. Once I get the room in
shape I'll update to the latest versions of everything and let you know
if I still have any issues.

On another ecasound note, but unrelated to the Subject: of this thread:
I've been recording the studio construcion sounds with a python-ecasound
script that randomly mixes the input of 4 microphones down to mono. I've
recorded so much that I've almost maxed out my audio drive. So, the
upshot of this is that I'll have to convert my pool of audio and also 
all of my ecasound python eci scripts to flac. According to some rough
calculations doing this will let me put off buying larger drives for
another 6-8 months.

I know you added flac support earlier this year and I did some
preliminary tests at that time. But, I ran into some issues and didn't
have time to work them out so I stuck with wav files. Have you had many
reports of success or problems with ecasound's flac support? Do you use
it yourself?

Anyway, I will necessarily need to have solid flac support in the next
few months. So, that stuff will be receiving some testing on my system

-Eric Rz.

More information about the Linux-audio-user mailing list