Audio DSP with C#

• Download source files - 20 Kb
• Download demo project - 48 Kb

Introduction

Garbe.Sound is a small .NET library for audio processing. The principal idea is to give programmers with a RAD environment for developing audio filters. With the basic classes, it comes with a few filters already implemented, like:

• Gain Filter
• Delay Filter
• LowPass Filter
• Mixer
• Reverberation
• Head Related Transfer Function (HRTF)
• Read and Write Wave Files (just mono yet)

The library is still a Beta 1 Version, but is already functional. Any comments are welcome!! :)

Using the code

One of the ideias of the library is to be easy of programming. Trying to do so, I choose a sistematic view of the classes in the library, where each filter can be perceived like a box with a input and output signal.

Almost all classes in the library inheritance from SoundObj class, that implements this basic sistematic view. This permits that you write code like this:

WaveReader    wr1 = new WaveReader("teste2.wav");
WaveReader    wr2 = new WaveReader("teste.wav");
Gain        ga1 = new Gain(0.5f);
Gain        ga2 = new Gain(0.5f);
Mixer        mx  = new Mixer(2);
WaveWriter    wwl = new WaveWriter("exit.wav", wr1.NumChannels, 
                                 wr1.SampleRate, wr1.BitsPerSamples, 1, true);
            
ga1.Input = wr1;
ga2.Input = wr2;
mx[0] = ga1;
mx[1] = ga2;
wwl.Input = mx;
            
for(int k = 0; k < wwl.Interations; k++)
{
    wr1.DoProcess();
    wr2.DoProcess();
    ga1.DoProcess();
    ga2.DoProcess();
    mx.DoProcess();
    wwl.DoProcess();
}

wr1.Close();
wr2.Close();
wwl.Close();

This is a very simple code that just have 2 signal inputs (teste.wav and teste2.wav), amplify both by 0.5 (ga1 and ga2 objects), mixes both in just one signal that is the output of the signal, wich is saved as exit.wav.

Links

• The SndObj Sound Object Library Page
  The page with the orignal work of Victor Lazzarini.
• Projects of Bill Gardner
  The Virtual Acoustic Room. Master's Thesis.
• Digital Audio Effects Conference
  This is the link for the site of the conferences.
• Image source method for simulating wave motion in rectangular enclosures
  The Master Project Dissertion from Peter Yardley.
• The CIPIC HRTF Database
  The publications from C.P. Brown, R.O. Duda, V.R. Algazi et al about HRTF.

History

• 02.09.2003 - Beta 1

Bugs and Comments

If you have any comments or find some bugs, I would love to hear about it and make it better.