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java實現pcm轉wav

import java.io.FileInputStream; import java.io.FileOutputStream; import java.io.IOException; public class PcmToWav {

public static void testPcmWav() throws IOException{
   String src = "d://synth.pcm";
   FileInputStream fis = new FileInputStream(src);
   FileOutputStream fos = new FileOutputStream("D://synth.wav");

   //計算長度
   int PCMSize = 0;
   byte[] buf = new byte[1024 * 4];
   int size = fis.read(buf);

   while (size != -1) {
      PCMSize += size;
      size = fis.read(buf);
    }
   fis.close();

   //填入引數,位元率等等。這裡用的是16位單聲道 8000 hz
   WaveHeader header = new WaveHeader(100);
   //長度欄位 = 內容的大小(PCMSize) + 頭部欄位的大小(不包括前面4位元組的識別符號RIFF以及fileLength本身的4位元組)
   header.fileLength = PCMSize + (44 - 8);
   header.fmtHdrLeth = 16;
   header.bitsPerSample = 16;
   header.channels = 1;
   header.formatTag = 0x0001;
   header.avgBytesPerSec = 8000;
   header.blockAlign = (short)(header.channels * header.bitsPerSample / 8);
   header.avgBytesPerSec = header.blockAlign * header.avgBytesPerSec;
   header.dataHdrLeth = PCMSize;

   byte[] h = header.getHeader();

   assert h.length == 44; //WAV標準,頭部應該是44位元組
   //write header
   fos.write(h, 0, h.length);
   //write data stream
   fis = new FileInputStream(src);
   size = fis.read(buf);
   while (size != -1) {
      fos.write(buf, 0, size);
      size = fis.read(buf);
   }
   fis.close();
   fos.close();
   System.out.println("Convert OK!");

} public static void main(String[] args) { try { testPcmWav(); } catch (IOException e) { e.printStackTrace(); } } }

所需WaveHeader類程式碼如下: import java.io.ByteArrayOutputStream;

import java.io.IOException;

public class WaveHeader {

public char fileID[] = { ‘R’, ‘I’, ‘F’, ‘F’ };

public int fileLength;

public char wavTag[] = { ‘W’, ‘A’, ‘V’, ‘E’ };

public char fmtHdrID[] = { ‘f’, ‘m’, ‘t’, ’ ’ };

public int fmtHdrLeth = 16;

public short formatTag = 1;

public short channels = 1;

public short sampleRate = 16000;

public short bitsPerSample = 16;

public short blockAlign = (short)(channels * bitsPerSample / 8);

public int avgBytesPerSec = blockAlign * sampleRate;

private char dataHdrID[] = { ‘d’, ‘a’, ‘t’, ‘a’ };

public int dataHdrLeth;

public WaveHeader (int fileLength){

this.fileLength = fileLength + (44 - 8);

dataHdrLeth = fileLength;

}

public WaveHeader (int fileLength, short channels, short sampleRate, short bitsPerSample){

this.fileLength = fileLength + (44 - 8);

dataHdrLeth = fileLength;

this.channels = channels;

this.sampleRate = sampleRate;

this.bitsPerSample = bitsPerSample;

blockAlign = (short)(channels * bitsPerSample / 8);

avgBytesPerSec = blockAlign * sampleRate;

}

public byte[] getHeader() throws IOException {

ByteArrayOutputStream bos = new ByteArrayOutputStream();

WriteChar(bos, fileID);

WriteInt(bos, fileLength);

WriteChar(bos, wavTag);

WriteChar(bos, fmtHdrID);

WriteInt(bos, fmtHdrLeth);

WriteShort(bos, formatTag);

WriteShort(bos, channels);

WriteInt(bos, sampleRate);

WriteInt(bos, avgBytesPerSec);

WriteShort(bos, blockAlign);

WriteShort(bos, bitsPerSample);

WriteChar(bos, dataHdrID);

WriteInt(bos, dataHdrLeth);

bos.flush();

byte[] r = bos.toByteArray();

bos.close();

return r;

}

private void WriteShort(ByteArrayOutputStream bos, int s)

throws IOException {

byte[] mybyte = new byte[2];

mybyte[1] = (byte) ((s << 16) >> 24);

mybyte[0] = (byte) ((s << 24) >> 24);

bos.write(mybyte);

}

private void WriteInt(ByteArrayOutputStream bos, int n) throws IOException {

byte[] buf = new byte[4];

buf[3] = (byte) (n >> 24);

buf[2] = (byte) ((n << 8) >> 24);

buf[1] = (byte) ((n << 16) >> 24);

buf[0] = (byte) ((n << 24) >> 24);

bos.write(buf);

}

private void WriteChar(ByteArrayOutputStream bos, char[] id) {

for (int i = 0; i < id.length; i++) {

char c = id[i];

bos.write©;

}

}

}