在Android开发中,可以使用MediaPlayer和Equalizer类来实现声音控制。以下是一些代码示例:
设置MediaPlayer的音频均衡器:
MediaPlayer mediaPlayer = new MediaPlayer();
mediaPlayer.setDataSource(context, audioUri);
Equalizer equalizer = new Equalizer(0, mediaPlayer.getAudioSessionId());
equalizer.setEnabled(true);
equalizer.setBandLevel(Equalizer.PARAM_BAND_LEVEL, (short) gain);
其中,gain值可以控制均衡器的增益。
使用SeekBar来控制Equalizer的频带:
Equalizer mEqualizer = new Equalizer(0, mediaPlayer.getAudioSessionId());
short[] bands = mEqualizer.getBandLevelRange();
short minLevel = bands[0];
short maxLevel = bands[1];
int numBands = mEqualizer.getNumberOfBands();
for (short i = 0; i < numBands; i++) {
final short band = i;
TextView freqTextView = new TextView(getContext());
freqTextView.setLayoutParams(new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT));
freqTextView.setText(mEqualizer.getCenterFreq(band) / 1000 + "Hz");
freqLinearLayout.addView(freqTextView);
SeekBar seekBar = new SeekBar(getContext());
seekBar.setLayoutParams(new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT));
seekBar.setMax(maxLevel - minLevel);
seekBar.setProgress(mEqualizer.getBandLevel(band));
seekBar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
@Override
public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
mEqualizer.setBandLevel(band, (short) (progress + minLevel));
}
...
});
gainLinearLayout.addView(seekBar);
}
上述代码将Equalizer的每个频带表示为一个SeekBar,用于控制该频带的增益。