any tips on how i would modify this code to add a gain argument to the biquad filter? I've looked at the documentation, but cant see any gain in the listed biquad constructor summary..would appreciate some help in implementing it into an example.
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- // Filter_03.pde
- // in this example, we apply a band-pass filter to a drum loop
- import beads.*;
- AudioContext ac;
- String sourceFile; // this will hold the path to our audio file
- SamplePlayer sp; // the SamplePlayer class will be used to play the audio file
- // standard gain objects
- Gain g;
- Glide gainValue;
- BiquadFilter filter1; // this is our filter unit generator
- void setup()
- {
- size(800, 600);
-
- ac = new AudioContext(); // create our AudioContext
- sourceFile = sketchPath("") + "Drum_Loop_01.wav";
- // Try/Catch blocks will inform us if the file can't be found
- try {
- // initialize our SamplePlayer, loading the file indicated by the sourceFile string
- sp = new SamplePlayer(ac, new Sample(sourceFile));
- }
- catch(Exception e)
- {
- // if there is an error, show an error message (at the bottom of the processing window)
- println("Exception while attempting to load sample!");
- e.printStackTrace(); // then print a technical description of the error
- exit(); // and exit the program
- }
-
- // we would like to play the sample multiple times, so we set KillOnEnd to false
- sp.setKillOnEnd(false);
- filter1 = new BiquadFilter(ac, BiquadFilter.BP_SKIRT, 5000.0f, 0.5f);
- filter1.addInput(sp); // connect the SamplePlayer to the filter
- // as usual, we create a gain that will control the volume of our sample player
- gainValue = new Glide(ac, 0.0, 20);
- g = new Gain(ac, 1, gainValue);
- g.addInput(filter1); // connect the filter to the gain
- ac.out.addInput(g); // connect the Gain to the AudioContext
- ac.start(); // begin audio processing
-
- background(0); // draw a black background
- text("Click to hear a band pass filter with cutoff set to 5000Hz.", 50, 50); // tell the user what to do
- }
- // although we're not drawing to the screen, we need to have a draw function
- // in order to wait for mousePressed events
- void draw(){}
- // this routine is called whenever a mouse button is pressed on the Processing sketch
- void mousePressed()
- {
- gainValue.setValue(0.9);
- sp.setToLoopStart(); // move the playback pointer to the first loop point (0.0)
- sp.start(); // play the audio file
- }
