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我混合了兩個wav文件。在輸出文件中，這兩個文件都是混合的，但有很多噪音。如何避免噪音並獲得清晰的輸出？我的標題是否已損壞或是其他內容？任何建議/幫助將不勝感激。如何在沒有噪音的情況下混合兩個wav文件？
這是代碼。 （在MainActivity中，只需調用mixSound（）。rawToWave（）函數爲wav文件寫入標題，我在創建混合文件後編寫標題）。
private void mixSound() throws IOException {
AudioTrack audioTrack = new AudioTrack(AudioManager.STREAM_MUSIC, 44100, AudioFormat.CHANNEL_OUT_STEREO, AudioFormat.ENCODING_PCM_16BIT, 44100, AudioTrack.MODE_STREAM);
InputStream in1 = getResources().openRawResource(R.raw.bird_caw1);
InputStream in2 = getResources().openRawResource(R.raw.bird_caw2);
byte[] arrayMusic1 = null;
arrayMusic1 = new byte[in1.available()];
arrayMusic1 = createMusicArray(in1);
in1.close();
byte[] arrayMusic2 = null;
arrayMusic2 = new byte[in2.available()];
arrayMusic2 = createMusicArray(in2);
in2.close();
byte[] output = new byte[arrayMusic1.length];
audioTrack.play();
for (int i = 0; i < output.length; i++) {
float samplef1 = arrayMusic1[i]/128.0f;
float samplef2 = arrayMusic2[i]/128.0f;
float mixed = samplef1 + samplef2;
// reduce the volume a bit:
mixed *= 0.8;
// hard clipping
if (mixed > 1.0f) mixed = 1.0f;
if (mixed < -1.0f) mixed = -1.0f;
byte outputSample = (byte) (mixed * 128.0f);
output[i] = outputSample;
}
audioTrack.write(output, 0, output.length);
convertByteToFile(output);
File file = new File(Environment.getExternalStorageDirectory().getPath() + "/mixed.wav");
rawToWave(file, file);
}
private void writeInt(final DataOutputStream output, final int value) throws IOException {
output.write(value >> 0);
output.write(value >> 8);
output.write(value >> 16);
output.write(value >> 24);
}
private void writeShort(final DataOutputStream output, final short value) throws IOException {
output.write(value >> 0);
output.write(value >> 8);
}
private void writeString(final DataOutputStream output, final String value) throws IOException {
for (int i = 0; i < value.length(); i++) {
output.write(value.charAt(i));
}
}
private void rawToWave(final File rawFile, final File waveFile) throws IOException {
byte[] rawData = new byte[(int) rawFile.length()];
DataInputStream input = null;
try {
input = new DataInputStream(new FileInputStream(rawFile));
input.read(rawData);
} finally {
if (input != null) {
input.close();
}
}
DataOutputStream output = null;
try {
output = new DataOutputStream(new FileOutputStream(waveFile));
// WAVE header
// see http://ccrma.stanford.edu/courses/422/projects/WaveFormat/
writeString(output, "RIFF"); // chunk id
writeInt(output, 36 + rawData.length); // chunk size
writeString(output, "WAVE"); // format
writeString(output, "fmt "); // subchunk 1 id
writeInt(output, 16); // subchunk 1 size
writeShort(output, (short) 1); // audio format (1 = PCM)
writeShort(output, (short) 1); // number of channels
writeInt(output, 8000); // sample rate
writeInt(output, 8000 * 2); // byte rate
writeShort(output, (short) 2); // block align
writeShort(output, (short) 16); // bits per sample
writeString(output, "data"); // subchunk 2 id
writeInt(output, rawData.length); // subchunk 2 size
// Audio data (conversion big endian -> little endian)
short[] shorts = new short[rawData.length/2];
ByteBuffer.wrap(rawData).order(ByteOrder.LITTLE_ENDIAN).asShortBuffer().get(shorts);
ByteBuffer bytes = ByteBuffer.allocate(shorts.length * 2);
for (short s : shorts) {
bytes.putShort(s);
}
output.write(bytes.array());
} finally {
if (output != null) {
output.close();
}
}
}