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MP3 Files get distorted during read process

I'm currently working on an application that plays back sound. I implemented playback for standard WAV File with the Java Sound API, no problems there, everything working fine. Now I want to add support for MP3 as well, but I'm having a strange problem: the playback gets distorted. I'm trying to figure out what I'm doing wrong, I would appreciate any leads in the right direction.
I'm using the Mp3SPI (http://www.javazoom.net/mp3spi/documents.html) for playing back the Mp3 Files.
I have already tried to take a look at the output and recorded a wav-file with the output I get from the mp3, then I compared the waveforms of the original and the recorded file. As it turns out, in the recorded file there are a lot of samples that are 0, or very close to it. Longer tones get broken up and the waveform returns to 0 all the time, then jumping back to the place the waveform is in the original.
I open the file like this:
private AudioInputStream mp3;
private AudioInputStream rawMp3;
private void openMP3(File file) {
// open the Audio INput Stream
try {
rawMp3 = AudioSystem.getAudioInputStream(file);
AudioFormat baseFormat = rawMp3.getFormat();
AudioFormat decodedFormat = new AudioFormat(AudioFormat.Encoding.PCM_SIGNED,
baseFormat.getSampleRate(),
16,
baseFormat.getChannels(),
baseFormat.getChannels() * 2,
baseFormat.getSampleRate(),
false);
mp3 = AudioSystem.getAudioInputStream(decodedFormat, rawMp3);
} catch (UnsupportedAudioFileException | IOException ex) {
Logger.getLogger(SoundFile.class.getName()).log(Level.SEVERE, null, ex);
}
}
The part where I read the Mp3 File:
byte[] data = new byte[length];
// read the data into the buffer
int nBytesRead = 0;
while (nBytesRead != - 1 && nBytesRead < length) {
nBytesRead = mp3.read(data, 0, data.length - nBytesRead);
}
Also I convert the byte-array to doubles, perhaps I do something wrong here (I'm fairly new to using bitwise operators, so maybe there is the problem
double[][] frameBuffer = new double[2][1024]; // 2 channel stereo buffer
int nFramesRead = 0;
int byteIndex = 0;
// convert the data into double and write it to frameBuffer
for (int i = 0; i < length; ++i) {
for (int c = 0; c < 2; ++c) {
byte a = data[byteIndex++];
byte b = data[byteIndex++];
int val = a | b << 8; // a is the least significant byte. | functions as a + here. b << 8 moves 8 zeroes to the end of b.
frameBuffer[c][i] = (double) val / (double) Short.MAX_VALUE;
nFramesRead++;
}
}
The double-array is then later used to play back the sound. When playing a wav file, I do the exact same thing to the buffer, so I'm pretty sure it has to be something during the read process, not me sending faulty bytes to the ouput.
I would expect this to work out of the box with Mp3SPI, but somehow something breaks the audio along the way.
I am also open to trying other libraries to play back the MP3, if you have any recommendations. Just a Decoder for the raw MP3 Data would actually be enough.

As it turns out, the AudioFormat from the mp3 (input) and the AudioFormat of the output didnt match, obviously resulting in distortion. So with those matched up, playback is fine!

Performance issues with converting mp3 file input stream to byte output stream

I would like to extract byte array from a given mp3 file in order to apply fast fourier transform on the latter. The performed FFT will give me some features for my pet-project musical -- recommendation system.
I have written the following code to extract the bytes from a given mp3 file:
public class TrackSample {
private static byte[] readBytesInPredefinedFormat(TargetDataLine format, InputStream inStream) throws IOException {
ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
byte[] buffer = new byte[8192];
int bytesRead;
while ((bytesRead = inStream.read(buffer)) > 0) {
int count = format.read(buffer, 0, buffer.length);
if (count > 0) {
byteArrayOutputStream.write(buffer, 0, count);
}
byteArrayOutputStream.write(buffer, 0, bytesRead);
}
byte[] bytes = byteArrayOutputStream.toByteArray();
byteArrayOutputStream.close();
inStream.close();
return bytes;
}
public static byte[] getTrackBytes(String pathToTrackSample) throws IOException, LineUnavailableException {
FileInputStream fileInputStream = new FileInputStream(pathToTrackSample);
final AudioFormat format = CurrentAudioFormat.getAudioFormat(); //Fill AudioFormat with the wanted settings
DataLine.Info info = new DataLine.Info(TargetDataLine.class, format);
TargetDataLine line = (TargetDataLine) AudioSystem.getLine(info);
line.open(format);
line.start();
return readBytesInPredefinedFormat(line, fileInputStream);
}
}
And the specified audio format is
public class CurrentAudioFormat {
public static AudioFormat getAudioFormat(){
float sampleRate = 44100;
int sampleSizeInBits = 8;
int channels = 1; //mono
boolean signed = true;
boolean bigEndian = true;
return new AudioFormat(sampleRate, sampleSizeInBits, channels, signed, bigEndian);
}
}
I tried to test this code on the following mp3 file:
File type ID: MPG3
Num Tracks: 1
----
Data format: 2 ch, 44100 Hz, '.mp3' (0x00000000) 0 bits/channel, 0 bytes/packet, 1152 frames/packet, 0 bytes/frame
no channel layout.
estimated duration: 104.176325 sec
audio bytes: 4167053
audio packets: 3988
bit rate: 320000 bits per second
packet size upper bound: 1052
maximum packet size: 1045
audio data file offset: 3169
optimized
audio 4591692 valid frames + 576 priming + 1908 remainder = 4594176
The system characteristics are:
processor: Intel core i5, 1.4 GHz;
RAM: DDR3, 4Gb
OS: Mac OS X El Captain
It took roughly 5 minutes to extract the byte array from this mp3 file.
What are the possible bottlenecks and how can I improve them?

To read the bytes you just need
while ((bytesRead = inStream.read(buffer)) > -1) {
byteArrayOutputStream.write(buffer, 0, bytesRead);
}
I dont know why you are reading twice.
To make sure that what you got is right try to resave it to a new audio file.
--
The standard way to read the audio file is
AudioInputStream audioInputStream=null;
try {
audioInputStream=AudioSystem.getAudioInputStream(new File(file));
}
catch(UnsupportedAudioFileException auf) { auf.printStackTrace(); }
then you pass this audioInputStream to your reading method.

converting pcm file to mp3 using liblame in android

I am using SimpleLameLibForAndroid to convert a pcm file that created using AudioRecord class in android,to mp3. I read the pcm file and encoded it into mp3 and then I write it in the file. the result mp3 file but is not correct and it has a lot of noise on it and really hard to understand that it was recorded pcm file.
these are recorded audio specifications(pcm file):
private static final int RECORDER_SAMPLERATE = 8000;
private static final int RECORDER_CHANNELS = AudioFormat.CHANNEL_IN_MONO;
private static final int RECORDER_AUDIO_ENCODING = AudioFormat.ENCODING_PCM_16BIT;
int BufferElements2Rec = 1024; // want to play 2048 (2K) since 2 bytes we use only 1024
int BytesPerElement = 2; // 2 bytes in 16bit format
recorder = new AudioRecord(MediaRecorder.AudioSource.MIC,
RECORDER_SAMPLERATE, RECORDER_CHANNELS,
RECORDER_AUDIO_ENCODING, BufferElements2Rec * BytesPerElement);
and this is my code that uses liblame for encode mp3 and write it to file:
//Encoder.Builder(int inSamplerate,int outChannel,int outSampleRate,int outBitrate)
Encoder en = new Encoder.Builder(8000, 1,8000,128).quality(7).create();
private int PCM_BUF_SIZE = 8192;
private int MP3_SIZE = 8192;
private void readFile() {
File pcm = new File("/sdcard/voice8K16bitmono.pcm");
File mp3 = new File("/sdcard/BOOOB.mp3");
pcm.setReadable(true);
mp3.setWritable(true);
try {
InputStream is = new FileInputStream(pcm);
BufferedInputStream bis = new BufferedInputStream(is);
bis.skip(44);//skip pcm header
OutputStream os = new FileOutputStream(mp3);
FileOutputStream fos = new FileOutputStream(mp3);
int n_bytes_read ;
int n_bytes_write;
int i;
byte mp3_buffer[] = new byte[MP3_SIZE];
byte pcm_buffer1[] = new byte[PCM_BUF_SIZE * 2];
do {
n_bytes_read = bis.read(pcm_buffer1 , 0 , PCM_BUF_SIZE);
if (n_bytes_read == 0){
n_bytes_write = en.flush(mp3_buffer);
}
else{
n_bytes_write = en.encodeBufferInterleaved(byte2short(pcm_buffer1) ,n_bytes_read , mp3_buffer);
}
bof.write(mp3_buffer, 0, PCM_BUF_SIZE);
} while (n_bytes_read > 0);
bis.close();
fos.close();
is.close();
en.close();
}catch (IOException e) {
e.printStackTrace();
}
}
private short[] byte2short(byte[] pcm_buffer1) {
short[] shorts = new short[pcm_buffer1.length/2];
ByteBuffer.wrap(pcm_buffer1).order(ByteOrder.LITTLE_ENDIAN).asShortBuffer().get(shorts);
return shorts;
}
how can i fix this code, is the bufferSizes true? using BufferedInputStream is correct? and...

I implemented a PCM to MP3 encoder just yesterday for my application using lame. I suggest not using SimpleLameLibForAndroid and instead adding lame to your project yourself. If you are using Android Studio, here is a good guide to get you started on that if you haven't done NDK before.
http://www.shaneenishry.com/blog/2014/08/17/ndk-with-android-studio/
As for implementing lame itself, below is a really good guide that I followed to get my application up and running. Use the wrapper.c from the .zip at the top of the page. This exposes useful methods so that you can avoid all the nasty Stream and Buffer stuff.
http://developer.samsung.com/technical-doc/view.do?v=T000000090
When all is said and done, the actual calls to the lame encoder are super simple as follows.
For initializing (use whatever settings you like):
public static final int NUM_CHANNELS = 1;
public static final int SAMPLE_RATE = 16000;
public static final int BITRATE = 64;
public static final int MODE = 1;
public static final int QUALITY = 7;
...
initEncoder(NUM_CHANNELS, SAMPLE_RATE, BITRATE, MODE, QUALITY);
For encoding (very easy):
int result = encodeFile(pcm.getPath(), mp3.getPath());
if (result == 0) {
//success
}
And of course destroy the encoder when done with destroyEncoder().

How to create a TargetDataLine using a binary array WebSocket?

I've created a byte array WebSocket that receives audio chunks in real time from the client's mic (navigator.getUserMedia). I'm already recording this stream to a WAV file in the server, after some time that the WebSocket stops to receive new byte arrays. The following code represents the current situation.
WebSocket
#OnMessage
public void message(byte[] b) throws IOException{
if(byteOutputStream == null) {
byteOutputStream = new ByteArrayOutputStream();
byteOutputStream.write(b);
} else {
byteOutputStream.write(b);
}
}
Thread that stores the WAV file
public void store(){
byte b[] = byteOutputStream.toByteArray();
try {
AudioFormat audioFormat = new AudioFormat(44100, 16, 1, true, true);
ByteArrayInputStream byteStream = new ByteArrayInputStream(b);
AudioInputStream audioStream = new AudioInputStream(byteStream, audioFormat, b.length);
DateTime date = new DateTime();
File file = new File("/tmp/"+date.getMillis()+ ".wav");
AudioSystem.write(audioStream, AudioFileFormat.Type.WAVE, file);
audioStream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
But instead of record a WAV file, my goal with this WebSocket is to process audio in real time using YIN pitch detection algorithm implemented on TarsosDSP library. In other words, this is basically execute the PitchDetectorExample, but using the data from the WebSocket instead of the Default Audio Device (OS mic). The following code represents how PitchDetectorExample is currently initializing live audio processing using the mic line provided by the OS.
private void setNewMixer(Mixer mixer) throws LineUnavailableException, UnsupportedAudioFileException {
if(dispatcher!= null){
dispatcher.stop();
}
currentMixer = mixer;
float sampleRate = 44100;
int bufferSize = 1024;
int overlap = 0;
final AudioFormat format = new AudioFormat(sampleRate, 16, 1, true, true);
final DataLine.Info dataLineInfo = new DataLine.Info(TargetDataLine.class, format);
TargetDataLine line;
line = (TargetDataLine) mixer.getLine(dataLineInfo);
final int numberOfSamples = bufferSize;
line.open(format, numberOfSamples);
line.start();
final AudioInputStream stream = new AudioInputStream(line);
JVMAudioInputStream audioStream = new JVMAudioInputStream(stream);
// create a new dispatcher
dispatcher = new AudioDispatcher(audioStream, bufferSize, overlap);
// add a processor
dispatcher.addAudioProcessor(new PitchProcessor(algo, sampleRate, bufferSize, this));
new Thread(dispatcher,"Audio dispatching").start();
}
There is a way to deal with WebSocket data as a TargetDataLine, so it will be possible to hook it up with AudioDispatcher and PitchProcessor? Somehow, i need to send the byte arrays received from the WebSocket to the audio processing Thread.
Another ideas on how reach this objective are welcome. Thanks!

I'm not sure you need an audioDispatcher. If you know how the bytes are encoded (PCM, 16bits le mono?) then you can convert them to floating points real-time and feed them to the pitchdetector algorithm, in your websocket you can do something like this (and forget about the inputstreams and audiodispatcher):
int index;
byte[] buffer = new byte[2048];
float[] floatBuffer = new float[1024];
FastYin detector = new FastYin(44100,1024);
public void message(byte[] b){
for(int i = 0 ; i < b.length; i++){
buffer[index] = b[i];
index++
if(index==2048){
AudioFloatConverter converter = AudioFloatConverter.getConverter(new Format(16bits, little endian, mono,...));
//converts the byte buffer to float
converter.toFloatArray(buffer,floatBuffer);
float pitch = detector.getPitch(floatBuffer);
//here you have your pitch info that you can use
index = 0;
}
}
You do need to watch the number of bytes that have passed: since two bytes represent one float (if 16bits pcm encoding is used) you need to start on even bytes. The endianness and samplerate are also important.
Regards
Joren

Generating sound with javax.sound.sampled

I'm trying to generate sound with Java. In the end, I'm willing to continuously send sound to the sound card, but for now I would be able to send a unique sound wave.
So, I filled an array with 44100 signed integers representing a simple sine wave, and I would like to send it to my sound card, but I just can't get it to work.
int samples = 44100; // 44100 samples/s
int[] data = new int[samples];
// Generate all samples
for ( int i=0; i<samples; ++i )
{
data[i] = (int) (Math.sin((double)i/(double)samples*2*Math.PI)*(Integer.MAX_VALUE/2));
}
And I send it to a sound line using:
AudioFormat format = new AudioFormat(Encoding.PCM_SIGNED, 44100, 16, 1, 1, 44100, false);
Clip clip = AudioSystem.getClip();
AudioInputStream inputStream = new AudioInputStream(ais,format,44100);
clip.open(inputStream);
clip.start();
My problem resides between these to code snippets. I just can't find a way to convert my int[] to an input stream!

Firstly I think you want short samples rather than int:
short[] data = new short[samples];
because your AudioFormat specifies 16-bit samples. short is 16-bits wide but int is 32 bits.
An easy way to convert it to a stream is:
Allocate a ByteBuffer
Populate it using putShort calls
Wrap the resulting byte[] in a ByteArrayInputStream
Create an AudioInputStream from the ByteArrayInputStream and format
Example:
float frameRate = 44100f; // 44100 samples/s
int channels = 2;
double duration = 1.0;
int sampleBytes = Short.SIZE / 8;
int frameBytes = sampleBytes * channels;
AudioFormat format =
new AudioFormat(Encoding.PCM_SIGNED,
frameRate,
Short.SIZE,
channels,
frameBytes,
frameRate,
true);
int nFrames = (int) Math.ceil(frameRate * duration);
int nSamples = nFrames * channels;
int nBytes = nSamples * sampleBytes;
ByteBuffer data = ByteBuffer.allocate(nBytes);
double freq = 440.0;
// Generate all samples
for ( int i=0; i<nFrames; ++i )
{
double value = Math.sin((double)i/(double)frameRate*freq*2*Math.PI)*(Short.MAX_VALUE);
for (int c=0; c<channels; ++ c) {
int index = (i*channels+c)*sampleBytes;
data.putShort(index, (short) value);
}
}
AudioInputStream stream =
new AudioInputStream(new ByteArrayInputStream(data.array()), format, nFrames*2);
Clip clip = AudioSystem.getClip();
clip.open(stream);
clip.start();
clip.drain();
Note: I changed your AudioFormat to stereo, because it threw an exception when I requested a mono line. I also increased the frequency of your waveform to something in the audible range.
Update - the previous modification (writing directly to the data line) was not necessary - using a Clip works fine. I have also introduced some variables to make the calculations clearer.

If you want to play a simple Sound, you should use a SourceDataLine.
Here's an example:
import javax.sound.sampled.*;
public class Sound implements Runnable {
//Specify the Format as
//44100 samples per second (sample rate)
//16-bit samples,
//Mono sound,
//Signed values,
//Big-Endian byte order
final AudioFormat format=new AudioFormat(44100f,16,2,true,true);
//Your output line that sends the audio to the speakers
SourceDataLine line;
public Sound(){
try{
line=AudioSystem.getSourceDataLine(format);
line.open(format);
}catch(LineUnavailableExcecption oops){
oops.printStackTrace();
}
new Thread(this).start();
}
public void run(){
//a buffer to store the audio samples
byte[] buffer=new byte[1000];
int bufferposition=0;
//a counter to generate the samples
long c=0;
//The pitch of your sine wave (440.0 Hz in this case)
double wavelength=44100.0/440.0;
while(true){
//Generate a sample
short sample=(short) (Math.sin(2*Math.PI*c/wavelength)*32000);
//Split the sample into two bytes and store them in the buffer
buffer[bufferposition]=(byte) (sample>>>8);
bufferposition++;
buffer[bufferposition]=(byte) (sample & 0xff);
bufferposition++;
//if the buffer is full, send it to the speakers
if(bufferposition>=buffer.length){
line.write(buffer,0,buffer.length);
line.start();
//Reset the buffer
bufferposition=0;
}
}
//Increment the counter
c++;
}
public static void main(String[] args){
new Sound();
}
}
In this example you're continuosly generating a sine wave, but you can use this code to play sound from any source you want. You just have to make sure that you format the samples right. In this case, I'm using raw, uncompressed 16-bit samples at a sample rate of 44100 Hz. However, if you want to play audio from a file, you can use a Clip object
public void play(File file){
Clip clip=AudioSystem.getClip();
clip.open(AudioSystem.getAudioInputStream(file));
clip.loop(1);
}