Firstly, in the following code what I am trying to do is find the length of a 2D byte array by using 'byteBuffer[0].length', but it is actually not working. When I am printing 'byteBuffer[0].length' it is giving the output as 4 instead of 882000, which (latter) should be the correct output according to the parameters I had passed. So how do I iterate it in my loop?
Secondly, I want to pass 'byteBuffer' in 'ByteArrayInputStream', but in 'ByteArrayInputStream' we cannot pass a 2D array. So is there a way of appending the values and use it there? And I also need to pass the values of 'Frequency1' and 'Frequency2' alternatively and save them in .wav format, so that I can play them accordingly in my media player. For example: an Ambulance's siren.
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.IOException;
import java.util.Scanner;
import javax.sound.sampled.AudioFileFormat;
import javax.sound.sampled.AudioFormat;
import javax.sound.sampled.AudioInputStream;
import javax.sound.sampled.AudioSystem;
public class AudioPlay {
public static void main(String[] args) throws IOException {
Scanner in = new Scanner(System.in);
final double SAMPLING_RATE = 44100; // Audio sampling rate
int time = in.nextInt(); //Time specified by user in seconds
int frequency1 = in.nextInt(); //Frequency specified by the user in hz
int frequency2 = in.nextInt();
//Size of buffer, in case time is 10 seconds it will be [2][441000]
float buffer[][] = new float[2][(int) (time * SAMPLING_RATE)];
for (int sample = 0; sample < buffer[0].length; sample++) {
double cycle = sample / SAMPLING_RATE; //Fraction of cycle between samples
buffer[0][sample] = (float) (Math.sin(2 * Math.PI * frequency1 * cycle)); //Storing value at every index of 1st row
buffer[1][sample] = (float) (Math.sin(2 * Math.PI * frequency2 * cycle)); //Storing value at every index of 2nd row
}
//Size of byteBuffer, in case time is 10sec it will be [2][882000]
byte byteBuffer[][] = new byte[2][(int)(buffer.length * 2)];
System.out.println(byteBuffer[0].length); // Giving wrong output
int count = 0;
for (int j = 0; j < byteBuffer.length; j++) {
for (int i = 0; i < byteBuffer[0].length; i++) {
final int x = (int) ((buffer[j][count++]) * Short.MAX_VALUE);
byteBuffer[j][i++] = (byte) x;
byteBuffer[j][i] = (byte) (x / 256); //Total Value of Byte
}
}
File out = new File("E:/RecordAudio7.wav"); //The path where user want the file data to be written
//Construct an audio format, using 44100hz sampling rate, 16 bit samples, mono, and big
// endian byte ordering
AudioFormat format = new AudioFormat((float) SAMPLING_RATE, 16, 1, true, false);
// It uses bytebuffer as its buffer array that contains bytes that may be read from the stream.
ByteArrayInputStream bais = new ByteArrayInputStream(byteBuffer[0]);
//Constructs an audio input stream that has the requested format and length in sample frames, using audio data
//from the specified input stream.
AudioInputStream audioInputStream = new AudioInputStream(bais, format, buffer.length);
//Writes a stream of bytes representing an audio file of the specified file type to the external file provided.
AudioSystem.write(audioInputStream, AudioFileFormat.Type.WAVE, out);
audioInputStream.close(); //Closes this audio input stream
}
}
I figured out the answer for the first part of my question. There was just a minor change in the code:
byte byteBuffer[][] = new byte[2][(int)(buffer[0].length * 2)];
instead of
byte byteBuffer[][] = new byte[2][(int)(buffer.length * 2)];