Add support for .mp3 files.

AUTHORS

@@ -176,6 +176,9 @@ Kaluzhny and released under the GNU GPL terms.
 Using Mono.Nat by Alan McGovern, Ben Motmans,
 Nicholas Terry distributed under the MIT license.
 
+Using MP3Sharp by Robert Bruke and Zane Wagner
+licensed under the GNU LGPL Version 3.
+
 Using ICSharpCode.SharpZipLib initially by Mike
 Krueger and distributed under the GNU GPL terms.
 

OpenRA.Mods.Common/AudioLoaders/Mp3Loader.cs

@@ -0,0 +1,60 @@
+#region Copyright & License Information
+/*
+ * Copyright 2007-2021 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.IO;
+using MP3Sharp;
+using OpenRA.Primitives;
+
+namespace OpenRA.Mods.Common.AudioLoaders
+{
+	public class Mp3Loader : ISoundLoader
+	{
+		bool ISoundLoader.TryParseSound(Stream stream, out ISoundFormat sound)
+		{
+			try
+			{
+				sound = new Mp3Format(stream);
+				return true;
+			}
+			catch
+			{
+				// Not a (supported) MP3
+			}
+
+			sound = null;
+			return false;
+		}
+	}
+
+	public sealed class Mp3Format : ISoundFormat
+	{
+		public int Channels { get { return mp3.ChannelCount; } }
+		public int SampleBits { get { return 16; } }
+		public int SampleRate { get { return mp3.Frequency; } }
+		public float LengthInSeconds { get { return mp3.Length * 8f / (2f * Channels * SampleRate); } }
+		public Stream GetPCMInputStream() { return new MP3Stream(Clone(this)); }
+		public void Dispose() { mp3.Dispose(); }
+
+		readonly MP3Stream mp3;
+		readonly Stream stream;
+
+		public Mp3Format(Stream stream)
+		{
+			mp3 = new MP3Stream(stream);
+			this.stream = stream;
+		}
+
+		Stream Clone(Mp3Format cloneFrom)
+		{
+			return SegmentStream.CreateWithoutOwningStream(cloneFrom.stream, 0, (int)cloneFrom.stream.Length);
+		}
+	}
+}

OpenRA.Mods.Common/OpenRA.Mods.Common.csproj

@@ -6,6 +6,7 @@
     <PackageReference Include="Microsoft.Win32.Registry" Version="4.7.0" />
     <PackageReference Include="OpenRA-FuzzyLogicLibrary" Version="1.0.1" />
     <PackageReference Include="DiscordRichPresence" Version="1.0.150" />
+    <PackageReference Include="MP3Sharp" Version="1.0.5" />
     <PackageReference Include="rix0rrr.BeaconLib" Version="1.0.2" />
     <PackageReference Include="Pfim" Version="0.9.1" />
     <PackageReference Include="System.Net.Http" Version="4.3.4" />