43 lines
1.2 KiB
Java
43 lines
1.2 KiB
Java
package audio;
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import java.io.IOException;
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import stdlib.StdAudio;
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import stdlib.StdIn;
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/**
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* This is a data-driven program that plays pure tones from
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* the notes on the chromatic scale, specified on standard input
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* by their distance from concert A.
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* % java PlayThatTune < elise.txt
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* @author Daniel Weschke
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*/
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public class PlayThatTune {
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public static void main(String[] args) throws IOException {
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if(args.length == 0) return;
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// repeat as long as there are more integers to read in
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while(!StdIn.isEmpty()) {
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// read in the pitch, where 0 = Concert A (A4)
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int pitch = StdIn.readInt();
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// read in duration in seconds
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double duration = StdIn.readDouble();
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// build sine wave with desired frequency
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double hz = 440 * Math.pow(2, pitch / 12.0);
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int N = (int) (StdAudio.SAMPLE_RATE * duration);
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double[] a = new double[N+1];
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int i;
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for(i=0; i<=N; i++) {
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a[i] = Math.sin(2 * Math.PI * i * hz / StdAudio.SAMPLE_RATE);
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}
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// play it using standard audio
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StdAudio.play(a);
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}
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}
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}
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