Play audio file from the assets directory

Question

I have the following code:

AssetFileDescriptor afd = getAssets().openFd("AudioFile.mp3");
player = new MediaPlayer();
player.setDataSource(afd.getFileDescriptor());
player.prepare();
player.start();

The problem is that, when I run this code, it starts playing all the audio files in the assets directory, in alphabetical order instead of just playing the audio file I requested. What am I doing wrong? Is there a better way to play audio files from the assets directory?

Follow-up question: Is there a difference between keeping audio files in the assets directory and keeping them in the res/raw directory? Besides the fact that they don't get ids if they are in the assets directory. If I move the audio files to the res/raw folder then I have a problem with reusing MediaPlayers because there is no id parameter for setDataSource(). I can't find a good guideline for handling this kind of problem.

score 251 · Accepted Answer · edited Jan 18 '13 at 19:05

251

player.setDataSource(afd.getFileDescriptor(),afd.getStartOffset(),afd.getLength());

Your version would work if you had only one file in the assets directory. The asset directory contents are not actually 'real files' on disk. All of them are put together one after another. So, if you do not specify where to start and how many bytes to read, the player will read up to the end (that is, will keep playing all the files in assets directory)

edited Jan 18 '13 at 19:05

Dheeraj Bhaskar

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answered Aug 02 '10 at 16:56

Sarwar Erfan

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It worked. Thanks. But I think my version SHOULD have also worked. – Catalin Morosan Aug 05 '10 at 16:17
61

Your version would work if you had only one file in the assets directory. The asset directory contents are not actually 'real files' on disk. All of them are put together one after another. So, if you do not specify where to start and how many bytes to read, the player will read up to the end (that is, will keep playing all the files in assets directory) – Sarwar Erfan Aug 09 '10 at 04:46
1

This is the code path that I am using but it doesn't work: http://stackoverflow.com/questions/9124378/mp3-audio-in-the-android-assets-folder-fails-to-play-from-a-signed-and-zip-align – Timothy Lee Russell Feb 16 '12 at 05:54
1

+1 for answering a completely unrelated question I had about asset files! – jjm Nov 10 '12 at 09:54
@SarwarErfan mind blown by the implementation of assets directory >_ – Warpzit Aug 13 '13 at 07:37
@SarwarErfan, when I try to use this method, I get a "java.io.FileNotFoundException: This file can not be opened as a file descriptor; it is probably compressed", is there any way I might be able to get around that problem? – seaders Feb 26 '14 at 14:54
I have total 10 files in assets folder and i want to read each file as per request.Like i want to play first audio from assets,what to do for that? – Chris Alan Nov 11 '14 at 09:00

score 81 · Answer 2 · edited Sep 17 '16 at 21:34

81

This function will work properly :)

// MediaPlayer m; /*assume, somewhere in the global scope...*/

public void playBeep() {
    try {
        if (m.isPlaying()) {
            m.stop();
            m.release();
            m = new MediaPlayer();
        }

        AssetFileDescriptor descriptor = getAssets().openFd("beepbeep.mp3");
        m.setDataSource(descriptor.getFileDescriptor(), descriptor.getStartOffset(), descriptor.getLength());
        descriptor.close();

        m.prepare();
        m.setVolume(1f, 1f);
        m.setLooping(true);
        m.start();
    } catch (Exception e) {
        e.printStackTrace();
    }
}

edited Sep 17 '16 at 21:34

JWL

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answered Nov 20 '12 at 07:24

Siddhpura Amit

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what is m? you are initializing m = new MediaPlayer(); after and used it before? – Umer Jan 29 '15 at 07:33
Hi @Umar, I have take Global variable MediaPlayer m = null; then I have assigned in playBeep() function – Siddhpura Amit Jan 29 '15 at 09:22
Keep in mind `MediaPlayer m` must be `static` or have another **reference**. If you have `m` in a function without any reference, `GC` will "collect" it – Menelaos Kotsollaris Mar 20 '15 at 20:40
sometimes audio does not play to the end – Roman Soviak Dec 20 '18 at 12:18
looping to true is that forever playing? – gumuruh May 18 '20 at 00:09

score 8 · Answer 3 · answered Mar 26 '19 at 12:44

start sound

startSound("mp3/ba.mp3");

method

private void startSound(String filename) {
    AssetFileDescriptor afd = null;
    try {
        afd = getResources().getAssets().openFd(filename);
    } catch (IOException e) {
        e.printStackTrace();
    }
    MediaPlayer player = new MediaPlayer();
    try {
        assert afd != null;
        player.setDataSource(afd.getFileDescriptor(), afd.getStartOffset(), afd.getLength());
    } catch (IOException e) {
        e.printStackTrace();
    }
    try {
        player.prepare();
    } catch (IOException e) {
        e.printStackTrace();
    }
    player.start();
}

This is useful when the file is in a subfolder of assets directory. Thank you. — Abdulwehab, Oct 25 '21 at 07:09

score 7 · Answer 4 · answered Nov 27 '18 at 09:48

Here my static version:

public static void playAssetSound(Context context, String soundFileName) {
    try {
        MediaPlayer mediaPlayer = new MediaPlayer();

        AssetFileDescriptor descriptor = context.getAssets().openFd(soundFileName);
        mediaPlayer.setDataSource(descriptor.getFileDescriptor(), descriptor.getStartOffset(), descriptor.getLength());
        descriptor.close();

        mediaPlayer.prepare();
        mediaPlayer.setVolume(1f, 1f);
        mediaPlayer.setLooping(false);
        mediaPlayer.start();
    } catch (Exception e) {
        e.printStackTrace();
    }
}

Mohammad Zaer · Answer 5 · 2018-08-15T22:00:43.253

Fix of above function for play and pause

  public void playBeep ( String word )
{
    try
    {
        if ( ( m == null ) )
        {

            m = new MediaPlayer ();
        }
        else if( m != null&&lastPlayed.equalsIgnoreCase (word)){
            m.stop();
            m.release ();
            m=null;
            lastPlayed="";
            return;
        }else if(m != null){
            m.release ();
            m = new MediaPlayer ();
        }
        lastPlayed=word;

        AssetFileDescriptor descriptor = context.getAssets ().openFd ( "rings/" + word + ".mp3" );
        long                start      = descriptor.getStartOffset ();
        long                end        = descriptor.getLength ();

        // get title
        // songTitle=songsList.get(songIndex).get("songTitle");
        // set the data source
        try
        {
            m.setDataSource ( descriptor.getFileDescriptor (), start, end );
        }
        catch ( Exception e )
        {
            Log.e ( "MUSIC SERVICE", "Error setting data source", e );
        }

        m.prepare ();
        m.setVolume ( 1f, 1f );
        // m.setLooping(true);
        m.start ();
    }
    catch ( Exception e )
    {
        e.printStackTrace ();
    }
}

Altivo · Answer 6 · 2020-04-22T21:45:10.527

this works for me:

public static class eSound_Def
{
  private static Android.Media.MediaPlayer mpBeep;

  public static void InitSounds( Android.Content.Res.AssetManager Assets )
  {
    mpBeep = new Android.Media.MediaPlayer();

    InitSound_Beep( Assets );
  }

  private static void InitSound_Beep( Android.Content.Res.AssetManager Assets )
  {
    Android.Content.Res.AssetFileDescriptor AFD;

    AFD = Assets.OpenFd( "Sounds/beep-06.mp3" );
    mpBeep.SetDataSource( AFD.FileDescriptor, AFD.StartOffset, AFD.Length );
    AFD.Close();

    mpBeep.Prepare();
    mpBeep.SetVolume( 1f, 1f );
    mpBeep.Looping = false;
  }

  public static void PlaySound_Beep()
  {
    if (mpBeep.IsPlaying == true) 
    {
      mpBeep.Stop();
      mpBeep.Reset();
      InitSound_Beep(); 
    }
    mpBeep.Start();
  }
}

In main activity, on create:

protected override void OnCreate( Bundle savedInstanceState )
{
  base.OnCreate( savedInstanceState );
  SetContentView( Resource.Layout.lmain_activity );
  ...
  eSound_Def.InitSounds( Assets );
  ...
}

how to use in code (on button click):

private void bButton_Click( object sender, EventArgs e )
{
  eSound_Def.PlaySound_Beep();
}

eUNIS is custom static class with variable Assets, that is reference to application assets. — Altivo, Apr 22 '20 at 21:47

Play audio file from the assets directory

6 Answers6

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