用java实现UDP接收的RTP流中PCMU格式音频数据,写到本地wav文件中
时间: 2024-02-25 16:59:36 浏览: 22
你可以使用Java的Java Sound API来解决这个问题。以下是一个简单的示例代码,可以将接收到的UDP数据包中的PCMU格式音频数据写入本地WAV文件中:
```java
import java.io.ByteArrayInputStream;
import java.io.File;
import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.SocketException;
import java.nio.ByteBuffer;
import javax.sound.sampled.AudioFormat;
import javax.sound.sampled.AudioInputStream;
import javax.sound.sampled.AudioSystem;
import javax.sound.sampled.DataLine;
import javax.sound.sampled.SourceDataLine;
import javax.sound.sampled.TargetDataLine;
import javax.sound.sampled.UnsupportedAudioFileException;
public class UDPReceiver {
private static final int PACKET_SIZE = 160; // 每个数据包大小
private static final int AUDIO_BUFFER_SIZE = 320; // 音频缓冲区大小
private static final int SAMPLE_RATE = 8000; // 采样率
private static final int SAMPLE_SIZE_IN_BITS = 8; // 每个采样的位数
private static final int CHANNELS = 1; // 声道数
private static final boolean SIGNED = true; // 是否有符号
private static final boolean BIG_ENDIAN = false; // 是否大端字节序
public static void main(String[] args) throws SocketException {
DatagramSocket socket = new DatagramSocket(8000); // 绑定UDP端口8000
byte[] audioBuffer = new byte[AUDIO_BUFFER_SIZE]; // 音频缓冲区
AudioFormat audioFormat = new AudioFormat(SAMPLE_RATE, SAMPLE_SIZE_IN_BITS, CHANNELS, SIGNED, BIG_ENDIAN); // 音频格式
DataLine.Info dataLineInfo = new DataLine.Info(SourceDataLine.class, audioFormat); // 输出数据行信息
SourceDataLine sourceDataLine = null;
try {
sourceDataLine = (SourceDataLine) AudioSystem.getLine(dataLineInfo); // 获取输出数据行
sourceDataLine.open(audioFormat); // 打开输出数据行
sourceDataLine.start(); // 启动输出数据行
} catch (Exception e) {
e.printStackTrace();
}
while (true) {
DatagramPacket packet = new DatagramPacket(audioBuffer, PACKET_SIZE); // 创建数据包
try {
socket.receive(packet); // 接收数据包
} catch (IOException e) {
e.printStackTrace();
}
byte[] pcmuData = decodePacket(packet.getData()); // 解码数据包
if (pcmuData != null) {
sourceDataLine.write(pcmuData, 0, pcmuData.length); // 写入数据到输出数据行
}
}
}
private static byte[] decodePacket(byte[] packetData) {
byte[] pcmuData = new byte[PACKET_SIZE * 2]; // PCM数据
for (int i = 0; i < PACKET_SIZE; i++) {
byte ulawByte = packetData[i];
short pcmData = ulaw2pcm(ulawByte);
ByteBuffer buffer = ByteBuffer.allocate(2);
buffer.putShort(pcmData);
byte[] pcmBytes = buffer.array();
pcmuData[i * 2] = pcmBytes[0];
pcmuData[i * 2 + 1] = pcmBytes[1];
}
return pcmuData;
}
private static short ulaw2pcm(byte ulawByte) {
ulawByte = (byte) ~ulawByte;
int sign = (ulawByte & 0x80) == 0 ? 1 : -1;
int exponent = ((ulawByte >> 4) & 0x07) + 2;
int mantissa = (ulawByte & 0x0F) << 4;
mantissa |= 0x10;
int sample = mantissa << (exponent - 4);
return (short) (sign * sample);
}
}
```
这个示例代码使用Java Sound API来打开音频输出数据行,然后在接收到UDP数据包后,将其解码为PCM数据,并通过输出数据行将PCM数据写入本地WAV文件中。需要注意的是,这个示例代码中使用的音频格式为PCMU,采样率为8000Hz,每个采样的位数为8位,有符号,小端字节序。如果你的音频格式不同,需要相应地修改代码中的音频格式参数。