(原创)speex与wav格式音频文件的互相转换(二)

之前写过了如何将speex与wav格式的音频互相转换，如果没有看过的请看一下连接
http://www.cnblogs.com/dongweiq/p/4515186.html
虽然自己实现了相关的压缩算法，但是发现还是与gauss的压缩比例差了一些，一部分是参数设置的问题，另外一部分是没有使用ogg的问题。

本来想研究一下gauss的ogg算法，然后将他录制的音频转为wav格式，再继续进行后面的频谱绘制之类的。

在后续的研究gauss的解码过程，他是先解了ogg的格式，然后分段，然后去掉speex的头，然后把一段段的speex数据再解码成pcm的原数据，最后使用audiotrack一段段播放出来了。audiotrack播放的时候是阻塞的，所以播了多久就解了多久。

既然他得到了一段段pcm的原数据，那我就可以去将这一段段的原数据拼起来，最后得到解码完成的整个的pcm数据，最后加上wav的头不就可以直接转换成wav格式的音频了么？？？

前天的时候想到这里，立马就去改了。

SpeexDecoder是gauss的demo里主要的解码类，我们复制一份，改名为SpeexFileDecoder

去掉里面跟播放相关的audiotrack变量，因为我们要得到的是解码数据，跟播放无关。

修改后代码如下

package com.sixin.speex;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.RandomAccessFile;
import java.util.ArrayList;
import java.util.List;

import android.media.AudioFormat;
import android.media.AudioManager;
import android.media.AudioTrack;
import android.os.RecoverySystem.ProgressListener;
import android.util.Log;

/**
* 采用Jspeex方案，首先解包，从ogg里面接出来，然后使用speex decode将speex转为wav数据并进行播放
*
* @author Honghe
*/
public class SpeexFileDecoder {

protected Speex speexDecoder;
private String errmsg = null;
private List<ProgressListener> listenerList = new ArrayList<ProgressListener>();
private File srcPath;
private File dstPath;

public SpeexFileDecoder(File srcPath, File dstPath) throws Exception {
this.srcPath = srcPath;
this.dstPath = dstPath;
}

private void initializeAndroidAudio(int sampleRate) throws Exception {
int minBufferSize = AudioTrack.getMinBufferSize(sampleRate, AudioFormat.CHANNEL_OUT_MONO, AudioFormat.ENCODING_PCM_16BIT);

if (minBufferSize < 0) {
throw new Exception("Failed to get minimum buffer size: " + Integer.toString(minBufferSize));
}
}

public void addOnMetadataListener(ProgressListener l) {
listenerList.add(l);
}

public String getErrmsg() {
return errmsg;
}

public void decode() throws Exception {
errmsg = null;
byte[] header = new byte[2048];
byte[] payload = new byte[65536];
final int OGG_HEADERSIZE = 27;
final int OGG_SEGOFFSET = 26;
final String OGGID = "OggS";
int segments = 0;
int curseg = 0;
int bodybytes = 0;
int decsize = 0;
int packetNo = 0;
// construct a new decoder
speexDecoder = new Speex();
speexDecoder.init();
// open the input stream
RandomAccessFile dis = new RandomAccessFile(srcPath, "r");
FileOutputStream fos = new FileOutputStream(dstPath);

int origchksum;
int chksum;
try {

// read until we get to EOF
while (true) {
if (Thread.interrupted()) {
dis.close();
return;
}

// read the OGG header
dis.readFully(header, 0, OGG_HEADERSIZE);
origchksum = readInt(header, 22);
readLong(header, 6);
header[22] = 0;
header[23] = 0;
header[24] = 0;
header[25] = 0;
chksum = OggCrc.checksum(0, header, 0, OGG_HEADERSIZE);

// make sure its a OGG header
if (!OGGID.equals(new String(header, 0, 4))) {
System.err.println("missing ogg id!");
errmsg = "missing ogg id!";
return;
}

/* how many segments are there? */
segments = header[OGG_SEGOFFSET] & 0xFF;
dis.readFully(header, OGG_HEADERSIZE, segments);
chksum = OggCrc.checksum(chksum, header, OGG_HEADERSIZE, segments);

/* decode each segment, writing output to wav */
for (curseg = 0; curseg < segments; curseg++) {

if (Thread.interrupted()) {
dis.close();
return;
}

/* get the number of bytes in the segment */
bodybytes = header[OGG_HEADERSIZE + curseg] & 0xFF;
if (bodybytes == 255) {
System.err.println("sorry, don't handle 255 sizes!");
return;
}
dis.readFully(payload, 0, bodybytes);
chksum = OggCrc.checksum(chksum, payload, 0, bodybytes);

/* decode the segment */
/* if first packet, read the Speex header */
if (packetNo == 0) {
if (readSpeexHeader(payload, 0, bodybytes, true)) {

packetNo++;
} else {
packetNo = 0;
}
} else if (packetNo == 1) { // Ogg Comment packet
packetNo++;
} else {

/* get the amount of decoded data */
short[] decoded = new short[160];
if ((decsize = speexDecoder.decode(payload, decoded, 160)) > 0) {
//把边解边播改为写文件
fos.write(ShortAndByte.shortArray2ByteArray(decoded), 0, decsize * 2);
}
packetNo++;
}
}
if (chksum != origchksum)
throw new IOException("Ogg CheckSums do not match");
}
} catch (Exception e) {
e.printStackTrace();
}
fos.close();
dis.close();
}

/**
* Reads the header packet.
*
* <pre>
*  0 -  7: speex_string: "Speex   "
*  8 - 27: speex_version: "speex-1.0"
* 28 - 31: speex_version_id: 1
* 32 - 35: header_size: 80
* 36 - 39: rate
* 40 - 43: mode: 0=narrowband, 1=wb, 2=uwb
* 44 - 47: mode_bitstream_version: 4
* 48 - 51: nb_channels
* 52 - 55: bitrate: -1
* 56 - 59: frame_size: 160
* 60 - 63: vbr
* 64 - 67: frames_per_packet
* 68 - 71: extra_headers: 0
* 72 - 75: reserved1
* 76 - 79: reserved2
* </pre>
*
* @param packet
* @param offset
* @param bytes
* @return
* @throws Exception
*/
private boolean readSpeexHeader(final byte[] packet, final int offset, final int bytes, boolean init) throws Exception {
if (bytes != 80) {
return false;
}
if (!"Speex   ".equals(new String(packet, offset, 8))) {
return false;
}
//        int mode = packet[40 + offset] & 0xFF;
int sampleRate = readInt(packet, offset + 36);
//        int channels = readInt(packet, offset + 48);
//        int nframes = readInt(packet, offset + 64);
//        int frameSize = readInt(packet, offset + 56);
//        RongXinLog.SystemOut("mode=" + mode + " sampleRate==" + sampleRate + " channels=" + channels
//                + "nframes=" + nframes + "framesize=" + frameSize);
initializeAndroidAudio(sampleRate);

if (init) {
// return speexDecoder.init(mode, sampleRate, channels, enhanced);
return true;
} else {
return true;
}
}

protected static int readInt(final byte[] data, final int offset) {
/*
* no 0xff on the last one to keep the sign
*/
return (data[offset] & 0xff) | ((data[offset + 1] & 0xff) << 8) | ((data[offset + 2] & 0xff) << 16) | (data[offset + 3] << 24);
}

protected static long readLong(final byte[] data, final int offset) {
/*
* no 0xff on the last one to keep the sign
*/
return (data[offset] & 0xff) | ((data[offset + 1] & 0xff) << 8) | ((data[offset + 2] & 0xff) << 16) | ((data[offset + 3] & 0xff) << 24) | ((data[offset + 4] & 0xff) << 32)
| ((data[offset + 5] & 0xff) << 40) | ((data[offset + 6] & 0xff) << 48) | (data[offset + 7] << 56);
}

protected static int readShort(final byte[] data, final int offset) {
/*
* no 0xff on the last one to keep the sign
*/
return (data[offset] & 0xff) | (data[offset + 1] << 8);
}

}

注意上面因为speex解码出来的是160个short类型的数组，而java写文件要求写入的是byte数组，所以我们还是用到了short转byte数组的方法shortArray2ByteArray，我封装了一个类。也贴在下边

package com.sixin.speex;

public class ShortAndByte {
/**
* @功能 短整型与字节的转换
* @param 短整型
* @return 两位的字节数组
*/
public static byte[] shortToByte(short number) {
int temp = number;
byte[] b = new byte[2];
for (int i = 0; i < b.length; i++) {
b[i] = new Integer(temp & 0xff).byteValue();// 将最低位保存在最低位
temp = temp >> 8; // 向右移8位
}
return b;
}

/**
* @功能 字节的转换与短整型
* @param 两位的字节数组
* @return 短整型
*/
public static short byteToShort(byte[] b) {
short s = 0;
short s0 = (short) (b[0] & 0xff);// 最低位
short s1 = (short) (b[1] & 0xff);
s1 <<= 8;
s = (short) (s0 | s1);
return s;
}

/**
* @说明 主要是为解析静态数据包，将一个字节数组转换为short数组
* @param b
*/
public static short[] byteArray2ShortArray(byte[] b) {
int len = b.length / 2;
int index = 0;
short[] re = new short[len];
byte[] buf = new byte[2];
for (int i = 0; i < b.length;) {
buf[0] = b[i];
buf[1] = b[i + 1];
short st = byteToShort(buf);
re[index] = st;
index++;
i += 2;
}
return re;
}

/**
* @说明 主要是为解析静态数据包，将一个short数组反转为字节数组
* @param b
*/
public static byte[] shortArray2ByteArray(short[] b) {
byte[] rebt = new byte[b.length * 2];
int index = 0;
for (int i = 0; i < b.length; i++) {
short st = b[i];
byte[] bt = shortToByte(st);
rebt[index] = bt[0];
rebt[index + 1] = bt[1];
index += 2;
}
return rebt;
}
}

读出来的原数据我们放入到了dstPath的文件，再来看看是怎么操作的呢？其中我还是修改了gauss的speexplayer方法。

我们复制speexPlayer方法，改名为SpeexFileDecoderHelper，按照如下方法修改

/**
*
*/
package com.sixin.speex;

import java.io.File;

import android.os.Handler;

/**
* @author honghe
*
*/
public class SpeexFileDecoderHelper {
private String srcName = null;
private String dstName = null;
private SpeexFileDecoder speexdec = null;
private OnSpeexFileCompletionListener speexListener = null;
private static final int speexdecode_completion = 1001;
private static final int speexdecode_error = 1002;

public Handler handler = new Handler() {
public void handleMessage(android.os.Message msg) {
int what = msg.what;
switch (what) {
case speexdecode_completion:
if (speexListener != null) {
speexListener.onCompletion(speexdec);
} else {
System.out.println("司信---------null===speexListener");
}
break;
case speexdecode_error:
if (speexListener != null) {
File file = new File(SpeexFileDecoderHelper.this.srcName);
if (null != file && file.exists()) {
file.delete();
}
speexListener.onError(null);
}
break;
default:
break;
}
};
};

public SpeexFileDecoderHelper(String fileName,String dstName, OnSpeexFileCompletionListener splistener) {
this.speexListener = splistener;
this.srcName = fileName;
this.dstName = dstName;
try {
speexdec = new SpeexFileDecoder(new File(this.srcName),new File(this.dstName));
} catch (Exception e) {
e.printStackTrace();
File file = new File(SpeexFileDecoderHelper.this.srcName);
if (null != file && file.exists()) {
file.delete();
}
}
}

public void startDecode() {
RecordDecodeThread rpt = new RecordDecodeThread();
Thread th = new Thread(rpt);
th.start();
}

public boolean isDecoding = false;

class RecordDecodeThread extends Thread {

public void run() {
try {
if (speexdec != null) {
isDecoding = true;
speexdec.decode();
if (null != speexdec.getErrmsg()) {
throw new Exception(speexdec.getErrmsg());
}
}
System.out.println("RecordPlayThread   文件转换完成");
if (isDecoding) {
handler.sendEmptyMessage(speexdecode_completion);
}
isDecoding = false;
} catch (Exception t) {
t.printStackTrace();
System.out.println("RecordPlayThread   文件转换出错");
handler.sendEmptyMessage(speexdecode_error);
isDecoding = false;
}
}
}

/**
* 结束播放
*/
public void stopDecode() {
isDecoding = false;
}

public String getSpxFileName() {
return this.srcName;
};
}

这个方法是开启了一个现成去解码，然后解码完成后会发送handler，调用回调方法，通知解码失败还是成功。OnSpeexFileCompletionListener这个很简单，我需要贴吗？还是贴上吧，省的被骂娘。

package com.sixin.speex;

/**
* Speex音频解码完成监听
* @author honghe
*
*/
public interface OnSpeexFileCompletionListener {
void onCompletion(SpeexFileDecoder speexdecoder);
void onError(Exception ex);
}

到此代码都贴出来了。什么？！还不会用？哦，我还没写怎么加wav头呢，那再写个方法吧

/**
* 语音转换
*
* @param name
* @param srcFileName spx文件名
* @param dstFileName 转换后得到文件的文件名
*/
public static void decodeSpx(Context context, String srcFileName, final String dstFileName) {
final String temppath = AudioFileFunc.getFilePathByName("temp.raw");
try {
// 如果是speex录音
if (srcFileName != null && srcFileName.endsWith(".spx")) {
if (mSpeexFileDecoderHelper != null && mSpeexFileDecoderHelper.isDecoding) {
stopMusic(context);
} else {
muteAudioFocus(context, true);
mSpeexFileDecoderHelper = new SpeexFileDecoderHelper(srcFileName, temppath, new OnSpeexFileCompletionListener() {

@Override
public void onError(Exception ex) {
System.out.println("转换错误");
}

@Override
public void onCompletion(SpeexFileDecoder speexdecoder) {
System.out.println("转换完成");
WaveJoin.copyWaveFile(temppath, dstFileName);
}
});
mSpeexFileDecoderHelper.startDecode();
}
} else {
System.out.println("音频文件格式不正确");
}

} catch (Exception e) {
e.printStackTrace();
}
}

copyWaveFile这个方法在哪里？去看开头的那个链接吧，上面有。不过在加wav头的时候要注意，加的头要和你录制音频的时候设置的参数一致，比如samplerate，声道数，framesize这些，我就设置错了一次，gauss录制音频的时候使用的是单声道，我加入的wav头的channel设置成了2，结果放出来的声音老搞笑了，就跟快放一样。有兴趣你可以试试。

代码已更新

代码链接如下：
https://github.com/dongweiq/study/tree/master/Record
我的github地址：https://github.com/dongweiq/study

欢迎关注，欢迎star o(∩_∩)o 。有什么问题请邮箱联系 dongweiqmail@gmail.com qq714094450