我有一个 pcm 文件，我想将其转换为 wav 文件。
有没有合适的api或代码？
问问题
10534 次
5 回答
7
这是我的代码
/**
* Write PCM data as WAV file
* @param os Stream to save file to
* @param pcmdata 8 bit PCMData
* @param srate Sample rate - 8000, 16000, etc.
* @param channel Number of channels - Mono = 1, Stereo = 2, etc..
* @param format Number of bits per sample (16 here)
* @throws IOException
*/
public void PCMtoFile(OutputStream os, short[] pcmdata, int srate, int channel, int format) throws IOException {
byte[] header = new byte[44];
byte[] data = get16BitPcm(pcmdata);
long totalDataLen = data.length + 36;
long bitrate = srate * channel * format;
header[0] = 'R';
header[1] = 'I';
header[2] = 'F';
header[3] = 'F';
header[4] = (byte) (totalDataLen & 0xff);
header[5] = (byte) ((totalDataLen >> 8) & 0xff);
header[6] = (byte) ((totalDataLen >> 16) & 0xff);
header[7] = (byte) ((totalDataLen >> 24) & 0xff);
header[8] = 'W';
header[9] = 'A';
header[10] = 'V';
header[11] = 'E';
header[12] = 'f';
header[13] = 'm';
header[14] = 't';
header[15] = ' ';
header[16] = (byte) format;
header[17] = 0;
header[18] = 0;
header[19] = 0;
header[20] = 1;
header[21] = 0;
header[22] = (byte) channel;
header[23] = 0;
header[24] = (byte) (srate & 0xff);
header[25] = (byte) ((srate >> 8) & 0xff);
header[26] = (byte) ((srate >> 16) & 0xff);
header[27] = (byte) ((srate >> 24) & 0xff);
header[28] = (byte) ((bitrate / 8) & 0xff);
header[29] = (byte) (((bitrate / 8) >> 8) & 0xff);
header[30] = (byte) (((bitrate / 8) >> 16) & 0xff);
header[31] = (byte) (((bitrate / 8) >> 24) & 0xff);
header[32] = (byte) ((channel * format) / 8);
header[33] = 0;
header[34] = 16;
header[35] = 0;
header[36] = 'd';
header[37] = 'a';
header[38] = 't';
header[39] = 'a';
header[40] = (byte) (data.length & 0xff);
header[41] = (byte) ((data.length >> 8) & 0xff);
header[42] = (byte) ((data.length >> 16) & 0xff);
header[43] = (byte) ((data.length >> 24) & 0xff);
os.write(header, 0, 44);
os.write(data);
os.close();
}
编辑：2016-01-11
public byte[] get16BitPcm(short[] data) {
byte[] resultData = new byte[2 * data.length];
int iter = 0;
for (double sample : data) {
short maxSample = (short)((sample * Short.MAX_VALUE));
resultData[iter++] = (byte)(maxSample & 0x00ff);
resultData[iter++] = (byte)((maxSample & 0xff00) >>> 8);
}
return resultData;
}
于 2013-08-28T14:03:16.707 回答
4
这应该很简单，因为 WAV = 元数据 + PCM（按此顺序）。这应该有效：
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, 44100); // sample rate
writeInt(output, RECORDER_SAMPLERATE * 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(fullyReadFileToBytes(rawFile));
} finally {
if (output != null) {
output.close();
}
}
}
byte[] fullyReadFileToBytes(File f) throws IOException {
int size = (int) f.length();
byte bytes[] = new byte[size];
byte tmpBuff[] = new byte[size];
FileInputStream fis= new FileInputStream(f);
try {
int read = fis.read(bytes, 0, size);
if (read < size) {
int remain = size - read;
while (remain > 0) {
read = fis.read(tmpBuff, 0, remain);
System.arraycopy(tmpBuff, 0, bytes, size - remain, read);
remain -= read;
}
}
} catch (IOException e){
throw e;
} finally {
fis.close();
}
return bytes;
}
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));
}
}
如何使用
使用起来非常简单。就这样称呼它：
File f1 = new File("/sdcard/44100Sampling-16bit-mono-mic.pcm"); // The location of your PCM file
File f2 = new File("/sdcard/44100Sampling-16bit-mono-mic.wav"); // The location where you want your WAV file
try {
rawToWave(f1, f2);
} catch (IOException e) {
e.printStackTrace();
}
这一切是如何运作的
如您所见，WAV 标头是 WAV 和 PCM 文件格式之间的唯一区别。假设您正在录制 16 位 PCM MONO 音频（根据您的代码，您是）。rawToWave 函数只是巧妙地向 WAV 文件添加标题，以便音乐播放器知道打开文件时会发生什么，然后在标题之后，它只是从最后一位开始写入 PCM 数据。
酷提示
如果你想改变你的声音的音调，或者制作一个语音转换器应用程序，你所要做的就是增加/减少writeInt(output, 44100); // sample rate代码中的值。降低它会告诉玩家以不同的速率播放它，从而改变输出音高。只是一点额外的“好消息”。:)
于 2016-07-29T05:33:10.517 回答
2
我还不能发表评论，但请注意get16BitPcmdevflow 的答案中的方法是 [奇怪地] 缩放输入数据。如果您已经有 16 位 pcm 数据要写入 wav 文件，则该方法应如下所示：
public byte[] get16BitPcm(short[] data) {
byte[] resultData = new byte[2 * data.length];
int iter = 0;
for (short sample : data) {
resultData[iter++] = (byte)(sample & 0x00ff);
resultData[iter++] = (byte)((sample & 0xff00) >>> 8);
}
return resultData;
}
于 2018-03-23T21:22:18.680 回答
0
我知道一个叫做“OperateWav”的东西，我在第一次实习期间在我的第一个项目中开发了一个转换器（linux c/c++）。我不确定这个本身是否存在以及它是否支持java。实际上wav文件很简单在 pcm 原始数据上添加 wav 格式标头...
于 2012-04-24T05:29:39.647 回答
0
这个资源WAVE PCM soundfile format帮助我将 PCM 数据解析为 WAVE。我已经基于它构建了一个库，它对我来说很好用。
于 2011-10-18T16:00:21.960 回答