我正在尝试将采样率为8000，单通道的PCM 16位转换为wav文件。
下面是代码：
private void rawToWaveafterUpload(final File rawFile, final File waveFile) throws IOException {
byte[] rawData = new byte[(int) rawFile.length()];
DataInputStream input = null;
if(rawFile.exists()) {
try {
FileInputStream rawFileInputStream = new FileInputStream(rawFile);
input = new DataInputStream(rawFileInputStream);
input.read(rawData);
} catch (Exception e) {
} finally {
if (input != null) {
input.close();
}
}
DataOutputStream output = null;
try {
output = new DataOutputStream(new FileOutputStream(waveFile));
// WAVE header
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();
//rawFile.delete();
}
}
}}
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));
}
}
当我播放PCM player App中的pcm时，音频播放正常。但我无法将此音频转换为WAV文件。音频没有播放。下面是PCM file which i need to convert to wave
答案 0 :(得分：0)
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
public class PCmTowav {
public static void main(String[] args) {
// TODO Auto-generated method stub
File read = new File("left_1.pcm");
File out = new File("left.wav");
try {
PCMToWAV(read, out, 1, 8000, 16);
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
/*
* static public void PCMToWAV(File input, File output, AudioFormat format)
* throws IOException { int bitsPerSample; switch (format.getEncoding()) { case
* AudioFormat.ENCODING_PCM_8BIT: bitsPerSample = 8; break; case
* AudioFormat.ENCODING_PCM_FLOAT: bitsPerSample = 32; break; case
* AudioFormat.ENCODING_PCM_16BIT: default: bitsPerSample = 16;
*
* } }
*/
/**
* @param input raw PCM data
* limit of file size for wave file: < 2^(2*4) - 36 bytes (~4GB)
* @param output file to encode to in wav format
* @param channelCount number of channels: 1 for mono, 2 for stereo, etc.
* @param sampleRate sample rate of PCM audio
* @param bitsPerSample bits per sample, i.e. 16 for PCM16
* @throws IOException in event of an error between input/output files
* @see <a href="http://soundfile.sapp.org/doc/WaveFormat/">soundfile.sapp.org/doc/WaveFormat</a>
*/
static public void PCMToWAV(File input, File output, int channelCount, int sampleRate, int bitsPerSample) throws IOException {
final int inputSize = (int) input.length();
try {
OutputStream encoded = new FileOutputStream(output);
// WAVE RIFF header
writeToOutput(encoded, "RIFF"); // chunk id
writeToOutput(encoded, 36 + inputSize); // chunk size
writeToOutput(encoded, "WAVE"); // format
// SUB CHUNK 1 (FORMAT)
writeToOutput(encoded, "fmt "); // subchunk 1 id
writeToOutput(encoded, 16); // subchunk 1 size
writeToOutput(encoded, (short) 1); // audio format (1 = PCM)
writeToOutput(encoded, (short) channelCount); // number of channelCount
writeToOutput(encoded, sampleRate); // sample rate
writeToOutput(encoded, sampleRate * channelCount * bitsPerSample / 8); // byte rate
writeToOutput(encoded, (short) (channelCount * bitsPerSample / 8)); // block align
writeToOutput(encoded, (short) bitsPerSample); // bits per sample
// SUB CHUNK 2 (AUDIO DATA)
writeToOutput(encoded, "data"); // subchunk 2 id
writeToOutput(encoded, inputSize); // subchunk 2 size
copy(new FileInputStream(input), encoded);
}catch(Exception e) {
}
}
/**
* Size of buffer used for transfer, by default
*/
private static final int TRANSFER_BUFFER_SIZE = 10 * 1024;
/**
* Writes string in big endian form to an output stream
*
* @param output stream
* @param data string
* @throws IOException
*/
public static void writeToOutput(OutputStream output, String data) throws IOException {
for (int i = 0; i < data.length(); i++)
output.write(data.charAt(i));
}
public static void writeToOutput(OutputStream output, int data) throws IOException {
output.write(data >> 0);
output.write(data >> 8);
output.write(data >> 16);
output.write(data >> 24);
}
public static void writeToOutput(OutputStream output, short data) throws IOException {
output.write(data >> 0);
output.write(data >> 8);
}
public static long copy(InputStream source, OutputStream output)
throws IOException {
return copy(source, output, TRANSFER_BUFFER_SIZE);
}
public static long copy(InputStream source, OutputStream output, int bufferSize) throws IOException {
long read = 0L;
byte[] buffer = new byte[bufferSize];
for (int n; (n = source.read(buffer)) != -1; read += n) {
output.write(buffer, 0, n);
}
return read;
}
}