from your code i can see that you just read data from the wav file and just import them to the AudioTrack. Wav files have a small header as you can see here https://ccrma.stanford.edu/courses/422/projects/WaveFormat/ So you have to skip the header and point your file descriptor at the right place where the actual audio data … Read more
OK, I’ve got this figured out. This post was crucial in helping me: http://computermusicblog.com/blog/2008/08/29/reading-and-writing-wav-files-in-java Basically, I used ByteArrayOutputStream to write the raw PCM data from AudioRecord, which then lets me get the byte array and its size when the process is done. I can then use that data in conjunction with the SampleRate, BitRate, and … Read more
The wav container just adds a simple header to the raw PCM data. The header includes the format, sample rate, and number of channels. Since the raw PCM data does not include this information, you will need to specify it on the command line. Options are specified before the file they apply to, so options … Read more
After testing this is what I came up with from modifying your code: package com.example.app; import android.app.Activity; import android.media.AudioManager; import android.media.MediaCodecInfo; import android.media.MediaFormat; import android.os.Bundle; import android.media.AudioFormat; import android.media.AudioRecord; import android.media.AudioTrack; import android.media.MediaCodec; import android.media.MediaRecorder.AudioSource; import android.util.Log; import java.io.IOException; import java.net.DatagramPacket; import java.net.DatagramSocket; import java.net.InetAddress; import java.net.SocketAddress; import java.net.SocketException; import java.nio.ByteBuffer; public class MainActivity extends … Read more
I’ve been wrestling with this exact same question for hours now, and my issue was mostly that when recording in 16 bits you have to be very careful about what you write to the output. The WAV file expects the data in Little Endian format, but using writeShort writes it to the output as Big … Read more
The complex data is interleaved, with real components at even indices and imaginary components at odd indices, i.e. the real components are at index 2*i, the imaginary components are at index 2*i+1. To get the magnitude of the spectrum at index i, you want: re = fft[2*i]; im = fft[2*i+1]; magnitude[i] = sqrt(re*re+im*im); Then you … Read more