Move AUD support to Mods.Cnc

OpenRA.Mods.Cnc/FileFormats/AudReader.cs

@@ -0,0 +1,143 @@
+#region Copyright & License Information
+/*
+ * Copyright 2007-2019 The OpenRA Developers (see AUTHORS)
+ * This file is part of OpenRA, which is free software. It is made
+ * available to you under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version. For more
+ * information, see COPYING.
+ */
+#endregion
+
+using System;
+using System.Collections.Generic;
+using System.IO;
+using OpenRA.Mods.Common.FileFormats;
+using OpenRA.Primitives;
+
+namespace OpenRA.Mods.Cnc.FileFormats
+{
+	[Flags]
+	enum SoundFlags
+	{
+		Stereo = 0x1,
+		_16Bit = 0x2,
+	}
+
+	enum SoundFormat
+	{
+		WestwoodCompressed = 1,
+		ImaAdpcm = 99,
+	}
+
+	public static class AudReader
+	{
+		public static byte[] LoadSound(byte[] raw, ref int index)
+		{
+			return ImaAdpcmReader.LoadImaAdpcmSound(raw, ref index);
+		}
+
+		public static float SoundLength(Stream s)
+		{
+			var sampleRate = s.ReadUInt16();
+			/*var dataSize = */ s.ReadInt32();
+			var outputSize = s.ReadInt32();
+			var flags = (SoundFlags)s.ReadByte();
+
+			var samples = outputSize;
+			if ((flags & SoundFlags.Stereo) != 0)
+				samples /= 2;
+
+			if ((flags & SoundFlags._16Bit) != 0)
+				samples /= 2;
+
+			return (float)samples / sampleRate;
+		}
+
+		public static bool LoadSound(Stream s, out Func<Stream> result, out int sampleRate)
+		{
+			result = null;
+			var startPosition = s.Position;
+			try
+			{
+				sampleRate = s.ReadUInt16();
+				var dataSize = s.ReadInt32();
+				var outputSize = s.ReadInt32();
+
+				var readFlag = s.ReadByte();
+				if (!Enum.IsDefined(typeof(SoundFlags), readFlag))
+					return false;
+
+				var readFormat = s.ReadByte();
+				if (!Enum.IsDefined(typeof(SoundFormat), readFormat))
+					return false;
+
+				var offsetPosition = s.Position;
+
+				result = () =>
+				{
+					var audioStream = SegmentStream.CreateWithoutOwningStream(s, offsetPosition, (int)(s.Length - offsetPosition));
+					return new AudStream(audioStream, outputSize, dataSize);
+				};
+			}
+			finally
+			{
+				s.Position = startPosition;
+			}
+
+			return true;
+		}
+
+		sealed class AudStream : ReadOnlyAdapterStream
+		{
+			readonly int outputSize;
+			int dataSize;
+
+			int currentSample;
+			int baseOffset;
+			int index;
+
+			public AudStream(Stream stream, int outputSize, int dataSize)
+				: base(stream)
+			{
+				this.outputSize = outputSize;
+				this.dataSize = dataSize;
+			}
+
+			public override long Length
+			{
+				get { return outputSize; }
+			}
+
+			protected override bool BufferData(Stream baseStream, Queue<byte> data)
+			{
+				if (dataSize <= 0)
+					return true;
+
+				var chunk = ImaAdpcmChunk.Read(baseStream);
+				for (var n = 0; n < chunk.CompressedSize; n++)
+				{
+					var b = baseStream.ReadUInt8();
+
+					var t = ImaAdpcmReader.DecodeImaAdpcmSample(b, ref index, ref currentSample);
+					data.Enqueue((byte)t);
+					data.Enqueue((byte)(t >> 8));
+					baseOffset += 2;
+
+					if (baseOffset < outputSize)
+					{
+						/* possible that only half of the final byte is used! */
+						t = ImaAdpcmReader.DecodeImaAdpcmSample((byte)(b >> 4), ref index, ref currentSample);
+						data.Enqueue((byte)t);
+						data.Enqueue((byte)(t >> 8));
+						baseOffset += 2;
+					}
+				}
+
+				dataSize -= 8 + chunk.CompressedSize;
+
+				return dataSize <= 0;
+			}
+		}
+	}
+}