我一直在使用一些代码,并且在复数转换中将转换转换为双精度而不是字节,现在所有数组在过去有数字时都返回零。想法?
代码:
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.util.ArrayList;
import java.util.LinkedList;
import java.util.List;
import javax.sound.sampled.AudioFormat;
import javax.sound.sampled.AudioInputStream;
import javax.sound.sampled.AudioSystem;
public class Decoder implements Runnable {
public AudioInputStream din;
public File decoding;
BufferedWriter write = new BufferedWriter(new FileWriter("STDOUT.txt"));
public Decoder(File f) throws Exception {
AudioInputStream in = AudioSystem.getAudioInputStream(f);
AudioFormat baseFormat = in.getFormat();
AudioFormat decodedFormat = new AudioFormat(
AudioFormat.Encoding.PCM_SIGNED, baseFormat.getSampleRate(),
16, baseFormat.getChannels(), baseFormat.getChannels() * 2,
baseFormat.getSampleRate(), false);
din = AudioSystem.getAudioInputStream(decodedFormat, in);
decoding = f;
}
@Override
public void run() {
byte[] buf = new byte[2048];
ArrayList<byte[]> bytes = new ArrayList<byte[]>();
int numBytesRead;
int total = 0;
try {
while ((numBytesRead = din.read(buf)) != -1) {
if (Converter.abort)
break;
System.out.println("Read " + numBytesRead);
total += numBytesRead;
bytes.add(buf);
buf = new byte[2048];
}
for (byte b : buf)
System.out.print(b + "-"); //No matter how I choose the array, all the bytes are zeros.
System.out.println("Total read: " + total + ". Amt of arrays: "
+ bytes.size());
ArrayList<double[]> fft_out = doFFT(bytes);
System.out.println("Writing bytes to FFTOut.txt");
BufferedWriter write = new BufferedWriter(new FileWriter(
"FFTOut.txt"));
for (double[] ba : fft_out) {
String bout = "";
for (double b : ba) {
bout += b + "";
}
bout += "\n";
write.write(bout);
}
write.close();
System.out.println("Done writing");
// TODO do more
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
din.close();
} catch (IOException e) {
System.exit(1);
}
Converter.done(decoding.getName());
}
}
private ArrayList<double[]> doFFT(List<byte[]> bytes) throws Exception {
for (byte b : bytes.get(6))
System.out.print(b + "-");
ArrayList<double[]> dout = new ArrayList<double[]>();
System.out.println("Amt of arrays: " + bytes.size());
for (int j = 0; j < bytes.size(); j++) {
byte[] arr = bytes.get(j);
Complex[] in = new Complex[arr.length];
for (int i = 0; i < arr.length; i++) {
in[i] = new Complex(arr[i], 0);
}
Complex[] out = FFT.fft(in);
double[] rep = new double[out.length];
for (int i = 0; i < out.length; i++) {
rep[i] = out[i].re();
}
dout.add(rep);
}
write.write("Processed " + bytes.size() + " arrays of bytes.");
return dout;
}
}
复杂类:
public class Complex {
private final double re; // the real part
private final double im; // the imaginary part
// create a new object with the given real and imaginary parts
public Complex(double real, double imag) {
re = real;
im = imag;
}
// return a string representation of the invoking Complex object
public String toString() {
if (im == 0)
return re + "";
if (re == 0)
return im + "i";
if (im < 0)
return re + " - " + (-im) + "i";
return re + " + " + im + "i";
}
// return abs/modulus/magnitude and angle/phase/argument
public double abs() {
return Math.hypot(re, im);
} // Math.sqrt(re*re + im*im)
public double phase() {
return Math.atan2(im, re);
} // between -pi and pi
// return a new Complex object whose value is (this + b)
public Complex plus(Complex b) {
Complex a = this; // invoking object
double real = a.re + b.re;
double imag = a.im + b.im;
return new Complex(real, imag);
}
// return a new Complex object whose value is (this - b)
public Complex minus(Complex b) {
Complex a = this;
double real = a.re - b.re;
double imag = a.im - b.im;
return new Complex(real, imag);
}
// return a new Complex object whose value is (this * b)
public Complex times(Complex b) {
Complex a = this;
double real = a.re * b.re - a.im * b.im;
double imag = a.re * b.im + a.im * b.re;
return new Complex(real, imag);
}
// scalar multiplication
// return a new object whose value is (this * alpha)
public Complex times(double alpha) {
return new Complex(alpha * re, alpha * im);
}
// return a new Complex object whose value is the conjugate of this
public Complex conjugate() {
return new Complex(re, -im);
}
// return a new Complex object whose value is the reciprocal of this
public Complex reciprocal() {
double scale = re * re + im * im;
return new Complex(re / scale, -im / scale);
}
// return the real or imaginary part
public double re() {
return re;
}
public double im() {
return im;
}
// return a / b
public Complex divides(Complex b) {
Complex a = this;
return a.times(b.reciprocal());
}
// return a new Complex object whose value is the complex exponential of
// this
public Complex exp() {
return new Complex(Math.exp(re) * Math.cos(im), Math.exp(re)
* Math.sin(im));
}
// return a new Complex object whose value is the complex sine of this
public Complex sin() {
return new Complex(Math.sin(re) * Math.cosh(im), Math.cos(re)
* Math.sinh(im));
}
// return a new Complex object whose value is the complex cosine of this
public Complex cos() {
return new Complex(Math.cos(re) * Math.cosh(im), -Math.sin(re)
* Math.sinh(im));
}
// return a new Complex object whose value is the complex tangent of this
public Complex tan() {
return sin().divides(cos());
}
// a static version of plus
public static Complex plus(Complex a, Complex b) {
double real = a.re + b.re;
double imag = a.im + b.im;
Complex sum = new Complex(real, imag);
return sum;
}
}