Play sound with OpenAL example

Program.cs

using System;
using System.Collections.Generic;
using System.IO;
using OpenTK.Audio;
using OpenTK.Audio.OpenAL;

namespace PlayALSoundExample
{
	class Program
	{
		public static void Main(string[] args)
		{
			if (args.Length < 1)
				throw new ArgumentException("Program needs at least one parameters.", "args");

			// Make audio context.
			var context = new AudioContext();

			// Declare variables.
			IList<short[]> buffers;
			ALFormat alFormat;
			int sampleRate;

			// Get the data from the wave file.
			getData(File.OpenRead(args[0]), out buffers, out alFormat, out sampleRate);

			// Get a list of buffer handles from OpenAL.
			var bufferHandles = AL.GenBuffers(buffers.Count);

			// Store all the data in OpenAL buffers.
			for (int i = 0; i < buffers.Count; i++)
				AL.BufferData (bufferHandles[i], alFormat, buffers[i], buffers[i].Length * sizeof(short), sampleRate);

			// Get a source from OpenAL.
			var sourceHandle = AL.GenSource();

			// Fill the source with the buffered data.
			AL.SourceQueueBuffers(sourceHandle, bufferHandles.Length, bufferHandles);

			// Play the source.
			AL.SourcePlay(sourceHandle);

			// Wait until we're done playing.
			while (AL.GetSourceState(sourceHandle) != ALSourceState.Stopped)
				System.Threading.Thread.Sleep(100);

			// Dispose source.
			AL.DeleteSource(sourceHandle);

			// Dispose buffers.
			AL.DeleteBuffers(bufferHandles);

			// Dispose AudioContext.
			context.Dispose();
		}

		private static void getData(Stream stream, out IList<short[]> buffers, out ALFormat alFormat, out int sampleRate)
		{
			using (var reader = new BinaryReader(stream))
			{
				// RIFF header
				var signature = new string(reader.ReadChars(4));
				if (signature != "RIFF")
					throw new NotSupportedException("Specified stream is not a wave file.");

				reader.ReadInt32(); // riffChunkSize

				var format = new string(reader.ReadChars(4));
				if (format != "WAVE")
					throw new NotSupportedException("Specified stream is not a wave file.");

				// WAVE header
				var formatSignature = new string(reader.ReadChars(4));
				if (formatSignature != "fmt ")
					throw new NotSupportedException("Specified wave file is not supported.");

				int formatChunkSize = reader.ReadInt32();
				reader.ReadInt16(); // audioFormat
				int numChannels = reader.ReadInt16();
				sampleRate = reader.ReadInt32();
				reader.ReadInt32(); // byteRate
				reader.ReadInt16(); // blockAlign
				int bitsPerSample = reader.ReadInt16();

				if (formatChunkSize > 16)
					reader.ReadBytes(formatChunkSize - 16);

				var dataSignature = new string(reader.ReadChars(4));

				if (dataSignature != "data")
					throw new NotSupportedException("Only uncompressed wave files are supported.");

				reader.ReadInt32(); // dataChunkSize

				alFormat = getSoundFormat(numChannels, bitsPerSample);

				var data = reader.ReadBytes((int)reader.BaseStream.Length);
				buffers = new List<short[]>();
				int count;
				int i = 0;
				const int bufferSize = 16384;

				while ((count = (Math.Min(data.Length, (i + 1) * bufferSize * 2) - i * bufferSize * 2) / 2) > 0)
				{
					var buffer = new short[bufferSize];
					convertBuffer(data, buffer, count, i * bufferSize * 2);
					buffers.Add(buffer);
					i++;
				}
			}
		}

		private static ALFormat getSoundFormat(int channels, int bits)
		{
			switch (channels)
			{
				case 1: return bits == 8 ? ALFormat.Mono8 : ALFormat.Mono16;
				case 2: return bits == 8 ? ALFormat.Stereo8 : ALFormat.Stereo16;
				default: throw new NotSupportedException("The specified sound format is not supported.");
			}
		}

		private static void convertBuffer(byte[] inBuffer, short[] outBuffer, int length, int inOffset = 0)
		{
			for (int i = 0; i < length; i++)
				outBuffer[i] = BitConverter.ToInt16(inBuffer, inOffset + 2 * i);
		}
	}
}