I've got an application where I will be playing 2 audio files simultaneously and the user will be attempting to hear the one (spoken words) over the other (background noise). With successful feedback input that they heard the file correctly, I want to decrease the volume of 1 (words) of the 2 files and play it again and they will attempt to hear it over the noise. I only want to decrease the volume of one file... the other one needs to remain constant (otherwise it defeats the purpose of trying to hear the one over the other). All I've found so far with the MediaManager is the ability to change the global volume of the application and not the specific audio clips within the application.
Any help is greatly appreciated.
My impression that the media player was global was incorrect. You can set the volume for this file and it will keep that volume even when you play a louder or quieter file (even when using the same mp). The oncompletion listener is important to releasing the file when over other wise you'll get exceptions and lose all sound. The logarithmic math function is important to getting the volume to scale appropriately between 0 & 100.
Assuming MAX_VOLUME is 100:
mp = MediaPlayer.create(getApplicationContext(), R.raw.noise);
final float noisevolume = (float) (1 - (Math.log(MAX_VOLUME - 50) / Math.log(MAX_VOLUME)));
mp.setVolume(noisevolume, noisevolume);
mp.start();
mp.setOnCompletionListener(new OnCompletionListener() {
#Override
public void onCompletion(MediaPlayer mp) {
mp.release();
}
});
Related
I have a number of mp3 files that I use with Android MediaPlayer to play from certain offsets.
Using seekTo() seems to stop at correct location. player.getCurrrentPosition() returns the correct offset, but in some cases the real position is off for as much as 200 ms. The files are about 3 minutes worth of recording and the incorrect offsets seem to appear at the end. Of some of the files.
I have the same effect either trying with Android 4.0.3 device or 4.3 emulator.
Anybody has experience with "finetuning" MediaPlayer offsets? Any experience why MediaPlayer might not be working correctly with some files? They are all CBR, stereo, some have sampling frequency 22050, some 44100, different bitrates.
I'm setting the offsets from another program and saving to mp3 tags, then in case of doubt verifying manually using Audacity. Audacity agrees with my estimate of what the correct offset is, MediaPlayer seems to disagree.
I'm aware that I could use AudioTrack with raw sound files and have a better control, however it might be impractical as there are many mp3 files, so using raw sound data will make pretty large application or many large data files.
The code is nothing fancy:
player.seekTo(start);
player.start();
CountDownTimer timer = new CountDownTimer(length, 100) {
#Override
public void onTick(long millisUntilFinished) {
if (player!=null) setInt(R.id.nLocation, player.getCurrentPosition());
}
#Override
public void onFinish() {
if (player!=null) {
if (player.isPlaying()) {
player.pause();
}
setInt(R.id.nLocation, player.getCurrentPosition());
player.stop();
player.release();
player = null;
}
}
};
timer.start();
I did not manage to find the rule why the MediaPlayer interprets offset (seekTo) differently for a group of MP3 files. For example when creating a new MP3 file with the same parameters from Audacity+Lame (MPEG1, Layer III, 44100 Hz, 192 Kb/s) it worked perfectly.
However:
this can be reproduced - rip MP3 file using Windows Media Player, settings: MP3, 192 kb/s [added when edited]
I found the workaround that seems to work for any recording.
The background - in order to tell MediaPlayer to play from certain offset, I store certain data in MP3 tags. I use a separate program to set up the playback (in frames): Label A, start frame=1000, length=100 frames, Label B, start #1500 etc. Now when I need to play it back, I read the MP3 headers, determine the frame length, for example 26.12245 ms/frame and calculate the offset (1000 frames will be 26122 ms).
The workaround is to store in MP3 tag also the frame count and length in ms (or pass through again and count the frames). Then when start MediaPlayer, compare MediaPlayer.getDuration() (MediaPlayer estimate) with the duration stored in MP3 tag. Then adjust the frame size:
adjustedFrameSizeMs = realFrameSizeMs + (player.getDuration()-storedDurationMs)/storedframeCount;
In my case (for the files with incorrect offset) the adjusted frame length always was between 26.08 and 26.09 ms (instead of 26.12245).
I attempted to try see if this is because Android plays the recording quicker (so it estimates the "real time", not the time according to frame size and frame count). It seems that it really does plays quicker. But even quicker than its own estimate. For example a recording of about 1 hour:
my estimate: 2448 s
MediaPlayer: 2444 s (4 sec difference)
Audacity: 2442 s (here we are in disagreement)
Foobar: 2448 s (another witness that agrees with my estimate :-)
MediaPlayer, real play time: 2438 s
The real playtime was 6 s (0.25%) less than MediaPlayer own estimate. Another attempt on a different sample gave the same percentage difference. However the fact that Audacity and Foobar did not always agree with my estimates, does not let me put all the blame on MediaPlayer.
I would like to play an audio file that starts on the left speaker and then switches to the right speaker.
I have tried doing something like this:
MediaPlayer mp = new MediaPlayer();
// Setup audio file
mp.start();
mp.setVolume(1.0F, 0F);
// Delay a second or two (I actually use a Handler and the postDelayed method)
mp.setVolume(0F, 1.0F);
but the sound comes through on both speakers the whole time.
How can I play audio in Android with either the left or right speaker muted (or at reduced volume)?
EDIT:
I got the correct behavior for a while while I was testing my app, but then it returned to what I described above with the exact same code base. Based on this, is there anything else I could check to find out what's going on?
One option would be
Start mediaplayer with setVolume(1.0F, 0F);
When you want to switch to other speaker, get current position of media player by using getCurrentPosition() method.
Then stop media player.
Then again start with setVolume(0F,1.0F);
Seek to the positin you got in 2nd step using seekTo() method
Done.
Overhead:This method may cause you some delay
It looks like you are doing it correctly according to the Android API http://developer.android.com/reference/android/media/MediaPlayer.html
public void setVolume (float leftVolume, float rightVolume)
Sets the volume on this player. This API is recommended for balancing the output of
audio streams within an application. Unless you are writing an application to control
user settings, this API should be used in preference to setStreamVolume(int, int, int)
which sets the volume of ALL streams of a particular type. Note that the passed volume
values are raw scalars in range 0.0 to 1.0. UI controls should be scaled logarithmically.
Parameters
leftVolume left volume scalar
rightVolume right volume scalar
My best advice is to try 0.0F instead of just 0F and then maybe trying to set the volume before you start playing the track then transition while it's playing.
Until now, I was setting my MediaPlayer volume by setting the stream volume. I don't want to do that anymore because it messes with user settings. I now take the value from a SeekBar (0 to 100) and do valueFromSeekBar / 100 to get a float between 0 and 1 to use in MediaPlayer.setVolume(float, float).
The problem is that the volume level doesn't seem to change. Here is how I set up the MediaPlayer:
player.setAudioStreamType(AudioManager.STREAM_ALARM);
player.setLooping(true);
player.prepare();
float alarmVolume = AudioUtils.getMediaPlayerScaledVolume(100, alarm.volume);
if(NetworkUtils.isInCall(context)) {
alarmVolume = IN_CALL_VOLUME;
}
mediaPlayer.setVolume(alarmVolume, alarmVolume); //I've even tried hardcoding 0.1f
No matter what I do, it seems like the value I put in MediaPlayer.setVolume gets ignored, and the volume of the stream (in this case the alarm stream) gets used instead. It's most noticeable when the stream volume is set to max, and I play two audio files, one with MediaPlayer.setVolume(1f, 1f) and the other with MediaPlayer.setVolume(0.01f, 0.01f). They are almost indistinguishable from one another. I need a way for my users to be able to position the SeekBar at 1 and get a barely audible sound, or at 100 and have the max sound. Is this possible or am I gonna have to go back to messing with streams?
Set volume:
it will set maximum value(100) to Alarm Stream.
amanager = (AudioManager)getSystemService(Context.AUDIO_SERVICE);
mediaPlayer.setAudioStreamType(AudioManager.STREAM_ALARM);
amanager.setStreamVolume(AudioManager.STREAM_ALARM, amanager.getStreamMaxVolume(AudioManager.STREAM_ALARM), AudioManager.FLAG_PLAY_SOUND);
Can it be you have two objects "player" and "mediaPlayer"? Here I just used that API, and it works as was to be expected.
I'm having a hard time with media player in android. Basically I try to play a song from my sd card which is downloading (some sort of streaming). So after the song was downloaded (20%) the song starts to play and if I leave it like this it works fine until the end. But if I try to seek at the end (over 20%) obviously it won't work because my seek position is over EOF file so I made this code inside a method
MediaPlayer mp = new MediaPlayer();
mp.setDataSource(sFilePath);
mp.prepare();
int offset = (progress * mp.getDuration()) / 100;
if (sCompleted) return;
sLastSeek = offset;
if (offset > sMediaPlayer.getDuration()) {
sMediaPlayer.reset();
sMediaPlayer.setDataSource(sFilePath);
sMediaPlayer.prepare();
} else {
sMediaPlayer.seekTo(offset);
}
Where sMediaPlayer is my mediaPlayer, and sFilePath is the file path. In theory the case I presented should be covered but when I seek over the file length the player is reseted (as the code says) but is not playing and this is very awkward and is over my powers.
Maybe the mediaPlayer stopt because it reaches the end of the song. Either start it again, refresh the file in steady intervals (say every 5 secs), or just use onCompletionListener. In the last case, when the file ends, you can reload the file and continue playing... mp.getCurrentPosition() to get where it left off playing.
I also noticed you refer to sMediaPlayer, but your MediaPlayer is defined as mp.
I am using the following code to play audio file.
I have tested the audio file on Android phone player & its playing quite loud.
When I am trying to play the same audio file from the following code , its very feeble.
Is there any problem with my code ? Can I increase the volume of the media file by changing any value ?
While testing , the volume of the Android device has been put to maximum value.
Kindly provide your inputs/sample code.
Thanks in advance.
public void playAlertSound() {
MediaPlayer player = MediaPlayer.create(this, R.raw.beep);
player.setLooping(false); // Set looping
player.setVolume(0.90f, 0.90f);
// Begin playing selected media
player.start();
// Release media instance to system
player.release();
}
Try player.setVolume(1.0f, 1.0f); instead; or just leave off that line entirely. You can also try scaling up the value past 1.0, although that's not really recommended.
You shouldn't call player.release() immediately. Try calling that in your onPause() or onDestroy() methods instead.
You might try using AudioManager.getStreamMaxVolume() to get the maximum volume and use it:
AudioManager audio =
(AudioManager) Context.getSystemService(Context.AUDIO_SERVICE);
int max = audio.getStreamMaxVolume(AudioManager.STREAM_MUSIC);
player.setVolume(max, max);
I'm not sure though if setVolume() expects absolute levels or multipliers from 0.0f to 1.0f. It mentions logarithmic adjustment, so you might try something closer to 1.0f like 0.95f or 1.0f itself.