使用Sharpavi Audio无法在C＃中录制

如何解决使用Sharpavi Audio无法在C＃中录制

**

通过Sharpavi录制

** 内部类记录器：IDisposable { 私有的只读int screenWidth; private readt int screenHeight; 私人只读AviWriter编写器； 私有只读IAviVideoStream videoStream; 私有只读IAviAudioStream audioStream; 私有只读WaveInEvent audioSource; 私有只读线程screenThread; 私有只读ManualResetEvent stopThread = new ManualResetEvent（false）; 私有只读AutoResetEvent videoFrameWritten = new AutoResetEvent（false）; 私有只读AutoResetEvent audioBlockWritten = new AutoResetEvent（false）;

        public Recorder(string fileName,FourCC codec,int quality,int audioSourceIndex,SupportedWaveFormat audioWaveFormat,bool encodeAudio,intaudioBitRate)
        {
            System.Windows.Media.Matrix toDevice;
            using (var source = new HwndSource(new HwndSourceParameters()))
            {
                toDevice = source.CompositionTarget.TransformToDevice;
            }

            screenWidth = (int)Math.Round(SystemParameters.PrimaryScreenWidth * toDevice.M11);
            screenHeight = (int)Math.Round(SystemParameters.PrimaryScreenHeight * toDevice.M22);

            // Create AVI writer and specify FPS
            writer = new AviWriter(fileName)
            {
                FramesPerSecond = 10,EmitIndex1 = true,};

            **// Create video stream**
       

 videoStream = CreateVideoStream(codec,quality);
            **// Set only name. Other properties were when creating stream,** 
            **// either explicitly by arguments or implicitly by the encoder used**
            videoStream.Name = "Screencast";

            if (audioSourceIndex >= 0)
            {
                var waveFormat = ToWaveFormat(audioWaveFormat);

                audioStream = CreateAudioStream(waveFormat,encodeAudio,audioBitRate);
                // Set only name. Other properties were when creating stream,// either explicitly by arguments or implicitly by the encoder used
                audioStream.Name = "Voice";

                audioSource = new WaveInEvent
                {
                    DeviceNumber = audioSourceIndex,WaveFormat = waveFormat,// Buffer size to store duration of 1 frame
                    BufferMilliseconds = (int)Math.Ceiling(1000 / writer.FramesPerSecond),NumberOfBuffers = 3,};
                audioSource.DataAvailable += audioSource_DataAvailable;
            }

            screenThread = new Thread(RecordScreen)
            {
                Name = typeof(Recorder).Name + ".RecordScreen",IsBackground = true
            };

            if (audioSource != null)
            {
                videoFrameWritten.Set();
                audioBlockWritten.Reset();
                audioSource.StartRecording();
            }
            screenThread.Start();
        }

        private IAviVideoStream CreateVideoStream(FourCC codec,int quality)
        {
            // Select encoder type based on FOURCC of codec
            if (codec == KnownFourCCs.Codecs.Uncompressed)
            {
                return writer.AddUncompressedVideoStream(screenWidth,screenHeight);
            }
            else if (codec == KnownFourCCs.Codecs.MotionJpeg)
            {
                return writer.AddMotionJpegVideoStream(screenWidth,screenHeight,quality
#if !FX45
                    // Implementation of this encoder for .NET 3.5 requires single-threaded access,forceSingleThreadedAccess: true
#endif
                    );
            }
            else
            {
                return writer.AddMpeg4VideoStream(screenWidth,(double)writer.FramesPerSecond,// It seems that all tested MPEG-4 VfW codecs ignore the quality affecting parameters passed through VfW API
                    // They only respect the settings from their own configuration dialogs,and Mpeg4VideoEncoder currently has no support for this
                    quality: quality,codec: codec,// Most of VfW codecs expect single-threaded use,so we wrap this encoder to special wrapper
                    // Thus all calls to the encoder (including its instantiation) will be invoked on a single thread although encoding (and writing) is performed asynchronously
                    forceSingleThreadedAccess: true);
            }
        }

        private IAviAudioStream CreateAudioStream(WaveFormat waveFormat,bool encode,int bitRate)
        {
            // Create encoding or simple stream based on settings
           
                return writer.AddAudioStream(
                    channelCount: waveFormat.Channels,samplesPerSecond: waveFormat.SampleRate,bitsPerSample: waveFormat.BitsPerSample);
          
        }

        private static WaveFormat ToWaveFormat(SupportedWaveFormat waveFormat)
        {
            switch (waveFormat)
            {
                case SupportedWaveFormat.WAVE_FORMAT_44M16:
                    return new WaveFormat(44100,16,1);
                case SupportedWaveFormat.WAVE_FORMAT_44S16:
                    return new WaveFormat(44100,2);
                default:
                    throw new NotSupportedException("Wave formats other than '16-bit 44.1kHz' are not currently supported.");
            }
        }

        public void Dispose()
        {
            stopThread.Set();
            screenThread.Join();
            if (audioSource != null)
            {
                audioSource.StopRecording();
                audioSource.DataAvailable -= audioSource_DataAvailable;
            }

            // Close writer: the remaining data is written to a file and file is closed
            writer.Close();

            stopThread.Close();
        }

        private void RecordScreen()
        {
            var frameInterval = TimeSpan.FromSeconds(1 / (double)writer.FramesPerSecond);
            var buffer = new byte[screenWidth * screenHeight * 4];
#if FX45
            Task videoWriteTask = null;
#else
            IAsyncResult videoWriteResult = null;
#endif
            var isFirstFrame = true;
            var timeTillNextFrame = TimeSpan.Zero;
            while (!stopThread.WaitOne(timeTillNextFrame))
            {
                var timestamp = DateTime.Now;

                GetScreenshot(buffer);

                // Wait for the previous frame is written
                if (!isFirstFrame)
                {
#if FX45
                    videoWriteTask.Wait();
#else
                    videoStream.EndWriteFrame(videoWriteResult);
#endif
                    videoFrameWritten.Set();
                }

                if (audioStream != null)
                {
                    var signalled = WaitHandle.WaitAny(new WaitHandle[] { audioBlockWritten,stopThread });
                    if (signalled == 1)
                        break;
                }

                // Start asynchronous (encoding and) writing of the new frame
#if FX45
                videoWriteTask = videoStream.WriteFrameAsync(true,buffer,buffer.Length);
#else
                videoWriteResult = videoStream.BeginWriteFrame(true,buffer.Length,null,null);
#endif

                timeTillNextFrame = timestamp + frameInterval - DateTime.Now;
                if (timeTillNextFrame < TimeSpan.Zero)
                    timeTillNextFrame = TimeSpan.Zero;

                isFirstFrame = false;
            }

            // Wait for the last frame is written
            if (!isFirstFrame)
            {
#if FX45
                videoWriteTask.Wait();
#else
                videoStream.EndWriteFrame(videoWriteResult);
#endif
            }
        }

        private void GetScreenshot(byte[] buffer)
        {
            using (var bitmap = new Bitmap(screenWidth,screenHeight))
            using (var graphics = Graphics.FromImage(bitmap))
            {
                graphics.CopyFromScreen(0,new System.Drawing.Size(screenWidth,screenHeight));
                var bits = bitmap.LockBits(new Rectangle(0,screenWidth,screenHeight),ImageLockMode.ReadOnly,PixelFormat.Format32bppRgb);
                Marshal.Copy(bits.Scan0,buffer.Length);
                bitmap.UnlockBits(bits);

                // Should also capture the mouse cursor here,but skipping for simplicity
                // For those who are interested,look at http://www.codeproject.com/Articles/12850/Capturing-the-Desktop-Screen-with-the-Mouse-Cursor
            }
        }

        private void audioSource_DataAvailable(object sender,WaveInEventArgs e)
        {
            var signalled = WaitHandle.WaitAny(new WaitHandle[] { videoFrameWritten,stopThread });
            if (signalled == 0)
            {
                audioStream.WriteBlock(e.Buffer,e.BytesRecorded);
                audioBlockWritten.Set();
            }
        }
    }