From 4aeec4f6a4add8d5e9d869f13abf8f940b51e1dd Mon Sep 17 00:00:00 2001
From: morkt <morkt@users.noreply.github.com>
Date: Thu, 7 Sep 2023 12:08:16 +0400
Subject: [PATCH] (SND): audio from Macromedia Director casts.

---
 ArcFormats/Macromedia/AudioSND.cs | 112 ++++++++++++++++++++++++++++++
 1 file changed, 112 insertions(+)
 create mode 100644 ArcFormats/Macromedia/AudioSND.cs

diff --git a/ArcFormats/Macromedia/AudioSND.cs b/ArcFormats/Macromedia/AudioSND.cs
new file mode 100644
index 00000000..f8ba395f
--- /dev/null
+++ b/ArcFormats/Macromedia/AudioSND.cs
@@ -0,0 +1,112 @@
+//! \file       AudioSND.cs
+//! \date       2023 Aug 30
+//! \brief      Macromedia Director WAVE audio resource.
+//
+// Copyright (C) 2023 by morkt
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to
+// deal in the Software without restriction, including without limitation the
+// rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+// sell copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+// IN THE SOFTWARE.
+//
+
+using System;
+using System.ComponentModel.Composition;
+
+namespace GameRes.Formats.Macromedia
+{
+    [Export(typeof(AudioFormat))]
+    public class SndAudio : AudioFormat
+    {
+        public override string         Tag { get => "SND"; }
+        public override string Description { get => "Macromedia Director audio resource"; }
+        public override uint     Signature { get => 0; }
+        public override bool      CanWrite { get => false; }
+
+        public override SoundInput TryOpen (IBinaryStream file)
+        {
+            if (!file.Name.HasExtension (".snd"))
+                return null;
+            int type = file.ReadUInt16();
+            if (type != 0x0200)
+                return null;
+            var reader = new Reader (file.AsStream, ByteOrder.BigEndian);
+            reader.Skip (2);
+            int count = reader.ReadU16();
+            if (0 == count)
+                return null;
+            int command = reader.ReadU16();
+            if (command != 0x8051)
+                return null;
+            reader.ReadI16();
+            int pos = reader.ReadI32();
+            if (pos != reader.Position)
+                return null;
+            ushort channels = 1;
+            ushort bps = 8;
+            reader.Skip (4);
+            int param = reader.ReadI32();
+            ushort sample_rate = reader.ReadU16();
+            reader.Skip (10);
+            byte encoding = reader.ReadU8();
+            byte freq = reader.ReadU8();
+            if (freq != 0x3C)
+                return null;
+            int frames_count = 0;
+            if (0 == encoding)
+            {
+                frames_count = param / channels;
+            }
+            else if (0xFF == encoding)
+            {
+                channels = (ushort)param;
+                frames_count = reader.ReadI32();
+                reader.Skip (22);
+                bps = reader.ReadU16();
+                reader.Skip (14);
+            }
+            else
+                throw new NotSupportedException (string.Format ("Not supported 'snd' encoding {0:X2}", encoding));
+            if (bps != 16 && bps != 8)
+                return null;
+
+            var format = new WaveFormat {
+                FormatTag = 1,
+                Channels = channels,
+                SamplesPerSecond = sample_rate,
+                BlockAlign = (ushort)(bps / 8),
+                BitsPerSample = bps,
+            };
+            format.SetBPS();
+            if (8 == bps)
+            {
+                var data = new StreamRegion (file.AsStream, file.Position);
+                return new RawPcmInput (data, format);
+            }
+            int sample_count = frames_count * channels;
+            var samples = file.ReadBytes (sample_count);
+            for (int i = 1; i < samples.Length; i += 2)
+            {
+                byte s = samples[i-1];
+                samples[i-1] = samples[i];
+                samples[i] = s;
+            }
+            var raw = new BinMemoryStream (samples);
+            file.Dispose();
+            return new RawPcmInput (raw, format);
+        }
+    }
+}