C# 实现录音操作

using Microsoft.DirectX.DirectSound;using System;using System.Collections.Generic;using System.IO;using System.Linq;using System.Text;using System.Threading;namespace 录音{    public class SoundRecord    {        #region 成员数据        private Capture mCapDev = null;              // 音频捕捉设备        private CaptureBuffer mRecBuffer = null;     // 缓冲区对象        private WaveFormat mWavFormat;               // 录音的格式        private int mNextCaptureOffset = 0;         // 该次录音缓冲区的起始点        private int mSampleCount = 0;               // 录制的样本数目        private Notify mNotify = null;               // 消息通知对象        public const int cNotifyNum = 16;           // 通知的个数        private int mNotifySize = 0;                // 每次通知大小        private int mBufferSize = 0;                // 缓冲队列大小        private Thread mNotifyThread = null;                 // 处理缓冲区消息的线程        private AutoResetEvent mNotificationEvent = null;    // 通知事件        private string mFileName = string.Empty;     // 文件保存路径        private FileStream mWaveFile = null;         // 文件流        private BinaryWriter mWriter = null;         // 写文件        #endregion        public SoundRecord()        {            //初始化音频捕捉设备              InitCaptureDevice();            //设定录音格式              mWavFormat = CreateWaveFormat();        }        #region 对外操作函数        /// <summary>          /// 创建录音格式,此处使用16bit,16KHz,Mono的录音格式          /// <summary>          private WaveFormat CreateWaveFormat()        {            WaveFormat format = new WaveFormat();            format.FormatTag = WaveFormatTag.Pcm;   // PCM              format.SamplesPerSecond = 16000;        // 采样率：16KHz              format.BitsPerSample = 16;              // 采样位数：16Bit              format.Channels = 1;                    // 声道：Mono              format.BlockAlign = (short)(format.Channels * (format.BitsPerSample / 8));  // 单位采样点的字节数               format.AverageBytesPerSecond = format.BlockAlign * format.SamplesPerSecond;            return format;            // 按照以上采样规格，可知采样1秒钟的字节数为 16000*2=32000B 约为31K          }        /// <summary>          /// 设定录音结束后保存的文件,包括路径          /// </summary>          /// <param name="filename">保存wav文件的路径名</param>          public void SetFileName(string filename)        {            mFileName = filename;        }        /// <summary>          /// 开始录音          /// </summary>          public void RecStart()        {            // 创建录音文件              CreateSoundFile();            // 创建一个录音缓冲区，并开始录音              CreateCaptureBuffer();            // 建立通知消息,当缓冲区满的时候处理方法              InitNotifications();            mRecBuffer.Start(true);        }        /// <summary>          /// 停止录音          /// </summary>          public void RecStop()        {            mRecBuffer.Stop();      // 调用缓冲区的停止方法，停止采集声音              if (null != mNotificationEvent)                mNotificationEvent.Set();       //关闭通知              mNotifyThread.Abort();  //结束线程              RecordCapturedData();   // 将缓冲区最后一部分数据写入到文件中              // 写WAV文件尾              mWriter.Seek(4, SeekOrigin.Begin);            mWriter.Write((int)(mSampleCount + 36));   // 写文件长度              mWriter.Seek(40, SeekOrigin.Begin);            mWriter.Write(mSampleCount);                // 写数据长度              mWriter.Close();            mWaveFile.Close();            mWriter = null;            mWaveFile = null;        }        #endregion        #region 对内操作函数        /// <summary>        /// 初始化录音设备,此处使用主录音设备.        /// </summary>        /// <returns>调用成功返回true,否则返回false</returns>        private bool InitCaptureDevice()        {            //获取默认音频捕捉设备            CaptureDevicesCollection devices = new CaptureDevicesCollection();  // 枚举音频捕捉设备            Guid deviceGuid = Guid.Empty;            if (devices.Count > 0)                deviceGuid = devices[0].DriverGuid;            else            {                //MessageBox.Show("系统中没有音频捕捉设备");                return false;            }            // 用指定的捕捉设备创建Capture对象            try            {                mCapDev = new Capture(deviceGuid);            }            catch (Microsoft.DirectX.DirectXException e)            {//MessageBox.Show(e.ToString());                return false;            }            return true;        }        /// <summary>        /// 创建录音使用的缓冲区        /// </summary>        private void CreateCaptureBuffer()        {            // 缓冲区的描述对象            CaptureBufferDescription bufferdescription = new CaptureBufferDescription();            if (null != mNotify)            {                mNotify.Dispose();                mNotify = null;            }            if (null != mRecBuffer)            {                mRecBuffer.Dispose();                mRecBuffer = null;            }            // 设定通知的大小,默认为1s钟            mNotifySize = (1024 > mWavFormat.AverageBytesPerSecond / 8) ? 1024 : (mWavFormat.AverageBytesPerSecond / 8);            mNotifySize -= mNotifySize % mWavFormat.BlockAlign;            // 设定缓冲区大小            mBufferSize = mNotifySize * cNotifyNum;            // 创建缓冲区描述            bufferdescription.BufferBytes = mBufferSize;            bufferdescription.Format = mWavFormat;           // 录音格式            // 创建缓冲区            mRecBuffer = new CaptureBuffer(bufferdescription, mCapDev);            mNextCaptureOffset = 0;        }        /// <summary>        /// 初始化通知事件,将原缓冲区分成16个缓冲队列,在每个缓冲队列的结束点设定通知点.        /// </summary>        /// <returns>是否成功</returns>        private bool InitNotifications()        {            if (null == mRecBuffer)            {                // MessageBox.Show("未创建录音缓冲区");                return false;            }            // 创建一个通知事件,当缓冲队列满了就激发该事件.            mNotificationEvent = new AutoResetEvent(false);            // 创建一个线程管理缓冲区事件            if (null == mNotifyThread)            {                mNotifyThread = new Thread(new ThreadStart(WaitThread));                mNotifyThread.Start();            }            // 设定通知的位置            BufferPositionNotify[] PositionNotify = new BufferPositionNotify[cNotifyNum + 1];            for (int i = 0; i < cNotifyNum; i++)            {                PositionNotify[i].Offset = (mNotifySize * i) + mNotifySize - 1;                PositionNotify[i].EventNotifyHandle = mNotificationEvent.SafeWaitHandle.DangerousGetHandle();            }            mNotify = new Notify(mRecBuffer);            mNotify.SetNotificationPositions(PositionNotify, cNotifyNum);            return true;        }        /// <summary>        /// 接收缓冲区满消息的处理线程        /// </summary>        private void WaitThread()        {            while (true)            {                // 等待缓冲区的通知消息                mNotificationEvent.WaitOne(Timeout.Infinite, true);                // 录制数据                RecordCapturedData();            }        }        /// <summary>        /// 将录制的数据写入wav文件        /// </summary>        private void RecordCapturedData()        {            byte[] CaptureData = null;            int ReadPos = 0, CapturePos = 0, LockSize = 0;            mRecBuffer.GetCurrentPosition(out CapturePos, out ReadPos);            LockSize = ReadPos - mNextCaptureOffset;            if (LockSize < 0)       // 因为是循环的使用缓冲区，所以有一种情况下为负：当文以载读指针回到第一个通知点，而Ibuffeoffset还在最后一个通知处                LockSize += mBufferSize;            LockSize -= (LockSize % mNotifySize);   // 对齐缓冲区边界,实际上由于开始设定完整,这个操作是多余的.            if (0 == LockSize)                return;            // 读取缓冲区内的数据            CaptureData = (byte[])mRecBuffer.Read(mNextCaptureOffset, typeof(byte), LockFlag.None, LockSize);            // 写入Wav文件            mWriter.Write(CaptureData, 0, CaptureData.Length);            // 更新已经录制的数据长度.            mSampleCount += CaptureData.Length;            // 移动录制数据的起始点,通知消息只负责指示产生消息的位置,并不记录上次录制的位置            mNextCaptureOffset += CaptureData.Length;            mNextCaptureOffset %= mBufferSize; // Circular buffer        }        /// <summary>        /// 创建保存的波形文件,并写入必要的文件头.        /// </summary>        private void CreateSoundFile()        {            // Open up the wave file for writing.            mWaveFile = new FileStream(mFileName, FileMode.Create);            mWriter = new BinaryWriter(mWaveFile);            /**************************************************************************                Here is where the file will be created. A                wave file is a RIFF file, which has chunks                of data that describe what the file contains.                A wave RIFF file is put together like this:                The 12 byte RIFF chunk is constructed like this:                Bytes 0 - 3 :  'R' 'I' 'F' 'F'                Bytes 4 - 7 :  Length of file, minus the first 8 bytes of the RIFF description.                                  (4 bytes for "WAVE" + 24 bytes for format chunk length +                                  8 bytes for data chunk description + actual sample data size.)                 Bytes 8 - 11: 'W' 'A' 'V' 'E'                 The 24 byte FORMAT chunk is constructed like this:                 Bytes 0 - 3 : 'f' 'm' 't' ' '                 Bytes 4 - 7 : The format chunk length. This is always 16.                 Bytes 8 - 9 : File padding. Always 1.                 Bytes 10- 11: Number of channels. Either 1 for mono,  or 2 for stereo.                 Bytes 12- 15: Sample rate.                 Bytes 16- 19: Number of bytes per second.                 Bytes 20- 21: Bytes per sample. 1 for 8 bit mono, 2 for 8 bit stereo or                                 16 bit mono, 4 for 16 bit stereo.                 Bytes 22- 23: Number of bits per sample.                 The DATA chunk is constructed like this:                 Bytes 0 - 3 : 'd' 'a' 't' 'a'                 Bytes 4 - 7 : Length of data, in bytes.                 Bytes 8 -: Actual sample data.               ***************************************************************************/            // Set up file with RIFF chunk info.            char[] ChunkRiff = { 'R', 'I', 'F', 'F' };            char[] ChunkType = { 'W', 'A', 'V', 'E' };            char[] ChunkFmt = { 'f', 'm', 't', ' ' };            char[] ChunkData = { 'd', 'a', 't', 'a' };            short shPad = 1;                // File padding            int nFormatChunkLength = 0x10;  // Format chunk length.            int nLength = 0;                // File length, minus first 8 bytes of RIFF description. This will be filled in later.            short shBytesPerSample = 0;     // Bytes per sample.            // 一个样本点的字节数目            if (8 == mWavFormat.BitsPerSample && 1 == mWavFormat.Channels)                shBytesPerSample = 1;            else if ((8 == mWavFormat.BitsPerSample && 2 == mWavFormat.Channels) || (16 == mWavFormat.BitsPerSample && 1 == mWavFormat.Channels))                shBytesPerSample = 2;            else if (16 == mWavFormat.BitsPerSample && 2 == mWavFormat.Channels)                shBytesPerSample = 4;            // RIFF 块            mWriter.Write(ChunkRiff);            mWriter.Write(nLength);            mWriter.Write(ChunkType);            // WAVE块            mWriter.Write(ChunkFmt);            mWriter.Write(nFormatChunkLength);            mWriter.Write(shPad);            mWriter.Write(mWavFormat.Channels);            mWriter.Write(mWavFormat.SamplesPerSecond);            mWriter.Write(mWavFormat.AverageBytesPerSecond);            mWriter.Write(shBytesPerSample);            mWriter.Write(mWavFormat.BitsPerSample);            // 数据块            mWriter.Write(ChunkData);            mWriter.Write((int)0);   // The sample length will be written in later.        }        #endregion    }}