(Note: I wrote this as something to tell to the clam-devel mailing list about some of my source-code commits)

About eight months ago, there was a foundation of something like an “audio club” in my university [1]. As soon i learned about that, i quickly got in touch with them and noticed that there was a major interest in analog issues (the only audio area with at least elective, courses in the university). So i told them about all the cool things that are available and ready to do with digital audio, mostly signal processing related. I talked in general, but of course i also talked about clam, with all its prototyping, real-time and easy development of plugins features. Even many of them ended installing and using it, and some even developing with more or less help. One thing to notice is that most of them are students from first years and most (but not all) are students with a basic programming level (because they are from electronics) but strong dsp knowledge (behind this is an university with more emphasis in theory than practice)
We started specifying plugins from a more abstract level (inputs/outputs/controls) and generating the source code base using
CLAM’s Templated Plugins Code Generator [2] and prototyping some simple applications. But one of the things we ended up doing was to take advantage of clam as platform to prototype medic related applications like filter ECG signal from noise in realtime, and some like _vice-versa_, i mean applying some processing knowledge from that area to audio.

Some of that work (one hour per week average) it’s now in the repo, most remarkable i think are filters work, by above the adaptative notch one (which even was used as a demo of a talk of one of the members about the steepest descent algorithm and its application to filter ECG signals)

Some development screenshots:
http://clam-project.org/wiki/Image:FilterByCoefExample.jpg
http://clam-project.org/wiki/Image:FilterExample-LP-HP.jpg
http://clam-project.org/wiki/Image:ThreeBandFilterOutputWithWhiteNoiseAsInput.jpg
http://clam-project.org/wiki/Image:GaussianWhiteNoiseHistogram.jpg
http://clam-project.org/wiki/Image:UniformWhiteNoiseHistogram.jpg

[0] FIUBA: Engineering Faculty of Buenos Aires University
[1] Group: http://code.google.com/p/club-audio-fiuba
Source code repo: http://groups.google.com/group/club_de_audio_fiuba
[2] http://audiores.uint8.com.ar/blog/2009/08/17/showing-a-little-about-clam-as-a-prototyping-tool-at-the-audio-club-of-fiuba/

algorithms , audio , blog , c++ , CLAM , ClubAudioFiuba , effects , english , free software , GPL , ideas , math , matlab , news , noise , plugins , programming , projects , python , signal processing

Share This/Compártelo

De casualidad (buscando otra cosa) me topé con esto: Audio Player Wordpress plugin. Parece bastante bien logrado y lo instalé en este blog… (además en este último tiempo venia averiguando sobre estos temas, ver: “Streaming audio from your website (mp3 and ogg!)” y “Many files to stream with cortado in the same page“). Al estar basado en flash, solo soporta mp3, pero es bastante configurable y tiene cosas copadas como la posibilidad de agregar audios por defecto al inicio o al final de cada track (útil por ejemplo para anuncios comerciales en podcasts o instrucciones de uso), distintas alternativas de mostrado de los audios en el feed, configuración de colores y otras cosas más.

También se puede usar en sitios no basados en wordpress (ver tutorial) y por ejemplo es el que usa digg.com para los podcasts (ver).

Ejemplo:

audio , blog , Castellano , flash , music , open source , podcast , web

Share This/Compártelo

If you noticed, in my last post I had added ready to play demos through del.icio.us streaming script, which it’s really simple, you only have to copy the code below and place it in anywhere you want in your HTML and your mp3 links will automatically become playable.

<script type="text/javascript" src="http://del.icio.us/js/playtagger"></script>

Then you have something like this: Elvis harmonized

 
There are many other options like odeo players with different sizes and also ready to embed where you want… Indeed, this google player (flash based) should work too:

<iframe style="border: 1px solid rgb(170, 170, 170); width: 500px; height: 25px;" id="musicPlayer"
src="http://mail.google.com/mail/html/audio.swf?audioUrl=URLMP3FILE MP3"></iframe>

 
But all those implementations only work with mp3 files and aren’t free software…, and that was annoying me a little (check this) so I was looking for ogg vorbis alternatives… and luckily I found one: Cortado.

It’s a Java applet from Fluendo which is able to play Ogg Theora, Ogg Vorbis, Mulaw audio, MJPEG and his own Smoke codec. It’s also free software and it’s released under GPL. As I read only works with SUN’s jre version… so isn’t completely free either… but I think is closer and I can choose ogg files again… btw, SUN java version should (or at least they say that) be GPL compatible very soon…

The bad thing: has poorly documentation (and not clear)… anyway I managed to get it working. I’ve downloaded the ogg vorbis last pre-compiled jar file and with an applet code like below, I get it working more or less quickly.

<applet archive="cortado-ovt.jar" code="com.fluendo.player.Cortado.class" width="320" height="20">
<param name="url" value="http://audiores.uint8.com.ar/files/audios/elvis-harmonized.ogg" />
<param name="local" value="false" />
<param name="framerate" value="5.0" />
<param name="keepaspect" value="true" />
<param name="video" value="false" />
<param name="audio" value="true" />
<param name="seekable" value="true" />
<param name="autoPlay" value="false" />
<param name="duration" value="203" /></applet>

Then you have something like this:

enjoy!

Update: For many applets in the same page check this post: “Many files to stream with cortado in the same page”

audio , blog , english , flash , free software , GPL , java , music , podcast , programming , web

Share This/Compártelo

Siguiendo la iniciativa de Avelino Herrera Morales, hecha en su muy buen blog he agregado el siguiente link a mi blogroll:

Acusmática: Con varios textos interesantes sobre acústica y síntesis de sonido. También vi que habia una fuerte orientación a programas y plataformas libres, hecho que también me agrado [1]. Cabe aclarar que no es un blog, sino un CMS integramente programado por ellos, felicitaciones por el esfuerzo! quedó muy bien!

Algunos links:

• INTRODUCCION A LA SINTESIS DE SONIDO
• ACÚSTICA BÁSICA Y AVANZADA

—

Otro sitio que parece interesante: RMS audio profesional

Se plantean como objetivo recopilar utilidades, informaciones, direcciones así como todo lo que sea de utilidad en el ámbito del audio profesional. Nace con el propósito de ser un referente en los recursos de internet en el ámbito del audio profesional.

Algunos links:

• INTRODUCCIÓN. EL SONIDO Y LAS ONDAS
  
• Cableado de conectores XLR y JACK
• El Decibelio

—

Seguiré agregando blogs a medida que conozca (tal vez actualizando este post o en otros nuevos si vale la pena) o me hagan saber.

Gracias Avelino Herrera Morales!

[1] Aunque los contenidos que vi, si bien son de libre distribución, no son “tan libres”, por ej. no se permite la creación de obras derivadas .

acoustics , audio , blog , Blogroll , Castellano , español , GNU/Linux , GPL , music

Share This/Compártelo