Minim core ugens analysis |
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Name | scaleBand | ||||||
Examples | /** * This sketch demonstrates very simply how you might use the inverse FFT to modify an audio signal.<br /> * Press 'f' to perform the forward FFT, then press 's' to scale the large frequency band.<br /> * Now press 'd' to take the inverse FFT. You will see that the wave form has a smaller amplitude.<br /> * <br /> * You might wonder how we knew which band to scale. You should read * <a href="http://code.compartmental.net/2007/03/21/fft-averages/">this blog post</a> about calculating * FFT averages for the answer to that question. * <p> * For more information about Minim and additional features, visit http://code.compartmental.net/minim/ */ import ddf.minim.analysis.*; import ddf.minim.*; import ddf.minim.signals.*; FFT fft; SineWave sine; float[] buffer; int bsize = 512; void setup() { size(512, 300, P3D); // create an FFT with a time-domain size the same as the size of buffer // it is required that these two values be the same // and also that the value is a power of two fft = new FFT(bsize, 44100); sine = new SineWave(600, 1, 44100); buffer = new float[bsize]; // fill the buffer with a sine wave sine.generate(buffer); } void draw() { background(0); noStroke(); fill(255, 128); // draw the waveform for(int i = 0; i < buffer.length; i++) { ellipse(i, 50 + buffer[i]*10, 2, 2); } noFill(); stroke(255); // draw the spectrum for(int i = 0; i < fft.specSize(); i++) { line(i, height, i, height - fft.getBand(i)); } stroke(255, 0, 0); line(width/2, height, width/2, 0); } void keyReleased() { if ( key == 'f' ) { println("Performing a Forward FFT on buffer."); fft.forward(buffer); } if ( key == 'd' ) { println("Performing an Inverse FFT and putting the result in buffer."); fft.inverse(buffer); } if ( key == 's' ) { println("Scaling frequency band 7 by 0.5."); fft.scaleBand(7, 0.5); } } |
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Description | Scales the amplitude of the ith frequency band
by s . You can use this to shape the spectrum before using
inverse() . |
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Syntax | scaleBand(i, s); |
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Parameters |
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Returns | None | ||||||
Usage | Web & Application | ||||||
Related | FFT |
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