Changeset 5

Timestamp:

11/08/08 16:03:59 (2 months ago)

Author:

Jeremy

Message:

Implemented tag reading via the Wave INFO chunk

Location:

trunk/AddIns/WaveAudio

Files:

• RiffReader.cs (copied) (copied from trunk/AddIns/WaveAudio/WaveReader.cs) (2 diffs, 1 prop)
• WaveAudio.cs (modified) (3 diffs)
• WaveAudio.csproj (modified) (2 diffs)
• WaveAudioFormat.cs (copied) (copied from trunk/AddIns/WaveAudio/WaveFormat.cs) (3 diffs, 1 prop)
• WaveFormatExChunk.cs (modified) (1 diff)
• WaveTag.cs (added)
• WaveTagFormat.cs (added)

trunk/AddIns/WaveAudio/RiffReader.cs

@@ -19 +19 @@
 
 using System;
+using System.Collections.Generic;
 using System.IO;
 using System.Text;
 using OmniEncoder.AudioModel.AddInViews;
 
-namespace OmniEncoder.AudioModel.Wave
+namespace OmniEncoder.WaveAudio
 {
-    class WaveReader : IDisposable
+    class RiffReader : IDisposable
     {
         readonly BinaryReader reader;
+        readonly Stack<uint> parentChunkLength = new Stack<uint>(2);
+        readonly Stack<string> parentChunkType = new Stack<string>(2);
+        readonly Stack<uint> parentChunkStart = new Stack<uint>(2);
 
-        internal WaveReader(string fileName)
+        internal RiffReader(string fileName)
         {
             reader = new BinaryReader(File.OpenRead(fileName), Encoding.ASCII);
 
-            try
+            if (new string(reader.ReadChars(4)) != "RIFF")
+                throw new AudioInvalidException("The file '" + fileName + "' does not contain a RIFF header.");
+
+            parentChunkLength.Push(reader.ReadUInt32() - 4);
+            parentChunkType.Push(new string(reader.ReadChars(4)));
+            parentChunkStart.Push(12);
+        }
+
+        internal string ChunkType
+        {
+            get { return parentChunkType.Peek(); }
+        }
+
+        internal bool Descend(string fourCC)
+        {
+            uint subChunkLength;
+            if (AdvanceToChunk(fourCC, out subChunkLength))
             {
-                if (new string(reader.ReadChars(4)) != "RIFF")
-                    throw new AudioInvalidException("The file '" + fileName + "' does not contain a RIFF header.");
-
-                reader.BaseStream.Seek(4, SeekOrigin.Current);
-
-                if (new string(reader.ReadChars(4)) != "WAVE")
-                    throw new AudioInvalidException("The file '" + fileName + "' is not a Wave file.");
+                parentChunkLength.Push(subChunkLength - 4);
+                parentChunkType.Push(new string(reader.ReadChars(4)));
+                parentChunkStart.Push((uint)reader.BaseStream.Position);
+                return true;
             }
-            catch (EndOfStreamException e)
-            {
-                throw new AudioInvalidException("The file '" + fileName + "' is missing data.", e);
-            }
+            else
+                return false;
         }
 
         internal byte[] ReadChunk(string fourCC)
         {
-            uint chunkSize = ReadChunkSize(fourCC);
-            return reader.ReadBytes((int)chunkSize);
+            uint chunkLength;
+            AdvanceToChunk(fourCC, out chunkLength);
+            return reader.ReadBytes((int)chunkLength);
         }
 
-        internal uint ReadChunkSize(string fourCC)
+        internal bool AdvanceToChunk(string fourCC, out uint chunkLength)
         {
-            reader.BaseStream.Seek(12, SeekOrigin.Begin);
+            reader.BaseStream.Seek(parentChunkStart.Peek(), SeekOrigin.Begin);
+
+            uint parentChunkEnd = parentChunkStart.Peek() + parentChunkLength.Peek();
 
             string currentFourCC = new string(reader.ReadChars(4));
-            uint chunkSize = reader.ReadUInt32();
+            uint currentChunkLength = reader.ReadUInt32();
 
             while (currentFourCC != fourCC)
             {
                 // Chunks are 2-byte aligned.
-                reader.BaseStream.Seek(chunkSize + chunkSize % 2, SeekOrigin.Current);
+                reader.BaseStream.Seek(currentChunkLength + currentChunkLength % 2, SeekOrigin.Current);
+
+                if (reader.BaseStream.Position == parentChunkEnd)
+                {
+                    chunkLength = 0;
+                    return false;
+                }
 
                 currentFourCC = new string(reader.ReadChars(4));
-                chunkSize = reader.ReadUInt32();
+                currentChunkLength = reader.ReadUInt32();
             }
 
-            return chunkSize;
+            chunkLength = currentChunkLength;
+            return true;
         }
 
@@ -96 +121 @@
         }
 
-        ~WaveReader()
+        ~RiffReader()
         {
             Dispose(false);

trunk/AddIns/WaveAudio/WaveAudio.cs

@@ -23 +23 @@
 using OmniEncoder.AudioModel.AddInViews;
 
-namespace OmniEncoder.AudioModel.Wave
+namespace OmniEncoder.WaveAudio
 {
     class WaveAudio : IAudio
@@ -33 +33 @@
         readonly TimeSpan length;
 
-        internal WaveAudio(byte[] formatChunk, uint audioSize)
+        internal WaveAudio(RiffReader reader)
         {
+            byte[] formatChunk = reader.ReadChunk("fmt ");
+
             // Read the array into a struct.
             GCHandle handle = GCHandle.Alloc(formatChunk, GCHandleType.Pinned);
@@ -60 +62 @@
             sampleRate = (int)waveFormatEx.SamplesPerSec;
 
+            // Use the size of the "data" chunk to calculate the length in seconds.
+            uint audioSize;
+            reader.AdvanceToChunk("data", out audioSize);
             int lengthInSeconds = (int)Math.Round(audioSize / (double)waveFormatEx.AvgBytesPerSec);
             length = new TimeSpan(0, 0, lengthInSeconds);

trunk/AddIns/WaveAudio/WaveAudio.csproj

@@ -54 +54 @@
   </ItemGroup>
   <ItemGroup>
+    <Compile Include="RiffReader.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />
     <Compile Include="WaveAudio.cs" />
-    <Compile Include="WaveFormat.cs" />
+    <Compile Include="WaveAudioFormat.cs" />
     <Compile Include="WaveFormatExChunk.cs" />
-    <Compile Include="WaveReader.cs" />
+    <Compile Include="WaveTag.cs" />
+    <Compile Include="WaveTagFormat.cs" />
   </ItemGroup>
   <ItemGroup>
@@ -64 +66 @@
       <Project>{DEC1B566-9D21-4528-84B7-8D127163AD0B}</Project>
       <Name>AudioModel.AddInViews</Name>
+      <Private>False</Private>
+    </ProjectReference>
+    <ProjectReference Include="..\..\AddInViews\TagModel.AddInViews\TagModel.AddInViews.csproj">
+      <Project>{E298AEFD-04A2-4E6C-9545-2F6659CC5AF1}</Project>
+      <Name>TagModel.AddInViews</Name>
       <Private>False</Private>
     </ProjectReference>

trunk/AddIns/WaveAudio/WaveAudioFormat.cs

@@ -23 +23 @@
 using OmniEncoder.AudioModel.AddInViews;
 
-namespace OmniEncoder.AudioModel.Wave
+namespace OmniEncoder.WaveAudio
 {
     [AddIn("Wave Audio")]
-    public class WaveFormat : IAudioFormat
+    public class WaveAudioFormat : IAudioFormat
     {
         readonly List<string> extensions;
 
-        public WaveFormat()
+        public WaveAudioFormat()
         {
             extensions = new List<string>(1);
@@ -36 +36 @@
         }
 
-        #region IAudioContainer Members
+        #region IAudioFormat Members
 
         public ReadOnlyCollection<string> Extensions
@@ -43 +43 @@
         }
 
-        public IAudio GetInfo(string fileName)
+        public IAudio GetAudio(string fileName)
         {
-            using (WaveReader reader = new WaveReader(fileName))
-            {
-                byte[] formatChunk = reader.ReadChunk("fmt ");
-                uint audioSize = reader.ReadChunkSize("data");
-                return new WaveAudio(formatChunk, audioSize);
-            }
+            using (RiffReader reader = new RiffReader(fileName))
+                return new WaveAudio(reader);
         }
 

trunk/AddIns/WaveAudio/WaveFormatExChunk.cs

@@ -18 +18 @@
  */
 
-namespace OmniEncoder.AudioModel.Wave
+namespace OmniEncoder.WaveAudio
 {
     struct WaveFormatEx