标签：libpcap c-3 linux c-4

我有一个文本文件,其有效载荷(十六进制)约为VoIP会话的RTP数据包,有谁知道如何将文本转换为文件. WAV音频使用C/C++？

PS：我正在使用GNU / Linux.

谢谢

解决方法:

我用Java做同样的事情.这是我用于测试目的的类,用于接收UDP RTP数据包(uLaw)并将其保存到WAV文件.有关如何使用它的示例,请参见主要方法.

public class UdpDataReceiver implements Runnable {

    private boolean isRunning = true;
    private int port = -1;
    private DatagramSocket socket;

    public UdpDataReceiver(int port) {
        this.port = port;
    }

    public void stop() {
        isRunning = false;
        socket.close();
    }

    @Override
    public void run() {
        try {
            socket = new DatagramSocket(port);
            System.out.println(" + Listening for UDP data on port " + port + ".");
        } catch (Exception e) {
            e.printStackTrace();
        }

        // Size of data buffer is insignificant; it just needs to be big enough to hold the UDP packet (or it will be truncated).
        byte[] data = new byte[512];
        DatagramPacket packet = new DatagramPacket(data, data.length);

        String file = null;
        FileOutputStream fos = null;
        try {
            // For now we'll just dump to a file.
            file = "C:\\tmp\\" + System.currentTimeMillis() + ".raw";
            fos = new FileOutputStream(file);

            while (isRunning) {
                try {
                    socket.receive(packet);
                } catch (SocketException se) {
                    // If we're just trying to tell the socket we're done, we'll get a SocketException.
                    if (isRunning) {
                        se.printStackTrace();
                    }
                }
                if (packet.getLength() > 12) {
                    // Strip off 12 bytes of header data.
                    fos.write(packet.getData(), packet.getOffset() + 12, packet.getLength() - 12);
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            try {
                fos.flush();
                fos.close();
                convertULawFileToWav(file);
            } catch (Exception e) {
            }
            System.out.println(" + Closed port " + port + " and wrote UDP packets to file: " + file);
        }
    }

    public static void convertULawFileToWav(String filename) {
        File file = new File(filename);
        if (!file.exists())
            return;
        try {
            long fileSize = file.length();
            int frameSize = 160;
            long numFrames = fileSize / frameSize;
            AudioFormat audioFormat = new AudioFormat(Encoding.ULAW, 8000, 8, 1, frameSize, 50, true);
            AudioInputStream audioInputStream = new AudioInputStream(new FileInputStream(file), audioFormat, numFrames);
            AudioSystem.write(audioInputStream, Type.WAVE, new File(file.getAbsolutePath().substring(0, file.getAbsolutePath().length() - 3) + "wav"));
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    // For testing...
    public static void main(String[] args) throws InterruptedException {
        UdpDataReceiver r1 = new UdpDataReceiver(65337);
        new Thread(r1).start();
        // Send data...
        Thread.sleep(30000);
        r1.stop();
    }

}

标签：libpcap,c-3,linux,c-4
来源： https://codeday.me/bug/20191201/2077638.html

本站声明： 1. iCode9 技术分享网（下文简称本站）提供的所有内容，仅供技术学习、探讨和分享；
2. 关于本站的所有留言、评论、转载及引用，纯属内容发起人的个人观点，与本站观点和立场无关；
3. 关于本站的所有言论和文字，纯属内容发起人的个人观点，与本站观点和立场无关；
4. 本站文章均是网友提供，不完全保证技术分享内容的完整性、准确性、时效性、风险性和版权归属；如您发现该文章侵犯了您的权益，可联系我们第一时间进行删除；
5. 本站为非盈利性的个人网站，所有内容不会用来进行牟利，也不会利用任何形式的广告来间接获益，纯粹是为了广大技术爱好者提供技术内容和技术思想的分享性交流网站。