簡單實用的PCM音頻播放器--沉寂幾年之后回歸的第一份筆記

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PCM音頻網絡流播放，至於用處，就不多解釋了。

一個簡單的類，基於NAudio，一個簡單的拼裝類，實例化時三個參數，依次是采樣率，系統播放設備Index，播放聲道，調用PlayData方法傳入PCM的音頻流即可，有流就傳進去，數據斷了，播放自動停。

接下來把代碼貼出來：

public class PCMPlayer
    {
        private MonoToStereoProvider16 monoToStereoProvider16;
        private BufferedWaveProvider bufferedWaveProvider;
        private WaveOut waveOut;
        private bool isRunning = false;
        private PCMPlayerChannel currentChannel;

        /// <summary>
        /// 
        /// </summary>
        /// <param name="sampleRate">采樣率8K至64K</param>
        /// <param name="deviceNumber">通過GetPlayDevices來獲取字典的KEY值</param>
        /// <param name="playerChannel">初始化時播放的聲道</param>
        public PCMPlayer(int sampleRate, int deviceNumber = 0, PCMPlayerChannel playerChannel = PCMPlayerChannel.Both)
        {
            currentChannel = playerChannel;
            WaveFormat = new WaveFormat(sampleRate, 16, 1);
            bufferedWaveProvider = new BufferedWaveProvider(WaveFormat);
            monoToStereoProvider16 = new MonoToStereoProvider16(bufferedWaveProvider);
            waveOut = new WaveOut();
            waveOut.DeviceNumber = deviceNumber;
            waveOut.Init(monoToStereoProvider16);
            waveOut.Play();
            isRunning = true;
        }

        public void PlayData(byte[] data)
        {
            if (!isRunning) return;
            bufferedWaveProvider.AddSamples(data, 0, data.Length);
        }

        public void ClosePlay()
        {
            isRunning = false;
            waveOut.Stop();
            waveOut.Dispose();
        }

        public bool SetPlayChannel(PCMPlayerChannel playerChannel)
        {
            if (!isRunning || waveOut == null || monoToStereoProvider16 == null) return false;
            switch (playerChannel)
            {
                case PCMPlayerChannel.Left:
                    {
                        monoToStereoProvider16.LeftVolume = 1.0f;
                        monoToStereoProvider16.RightVolume = 0.0f;
                    }
                    break;
                case PCMPlayerChannel.Right:
                    {
                        monoToStereoProvider16.LeftVolume = 0.0f;
                        monoToStereoProvider16.RightVolume = 1.0f;
                    }
                    break;
                case PCMPlayerChannel.Both:
                    {
                        monoToStereoProvider16.LeftVolume = 1.0f;
                        monoToStereoProvider16.RightVolume = 1.0f;
                    }
                    break;
                default: return false;
            }
            return true;
        }

        public WaveFormat WaveFormat { get; private set; }

        public static Dictionary<int, WaveOutCapabilities> GetPlayDevices
        {
            get
            {
                Dictionary<int, WaveOutCapabilities> result = new Dictionary<int, WaveOutCapabilities>();
                try
                {
                    int count = WaveOut.DeviceCount;
                    for (int i = 0; i < count; i++)
                    {
                        var item = WaveOut.GetCapabilities(i);
                        result.Add(i, item);
                    }
                }
                catch { }
                return result;
            }
        }
    }

    public enum PCMPlayerChannel
    {
        Left,
        Right,
        Both
    }

 

預告：下一篇簡單講一下音頻流網絡傳輸時壓縮與解壓（基於NSpeex的音頻10倍壓縮，肉耳聽不出損耗）