Initial commit

Scripts/TaglibSharp/Aac/AudioHeader.cs

@@ -0,0 +1,415 @@
+//
+// AudioHeader.cs: Provides information about an ADTS AAC audio stream.
+//
+// Copyright (C) 2009 Patrick Dehne
+// 
+// This library is free software; you can redistribute it and/or modify
+// it  under the terms of the GNU Lesser General Public License version
+// 2.1 as published by the Free Software Foundation.
+//
+// This library is distributed in the hope that it will be useful, but
+// WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+// Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public
+// License along with this library; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
+// USA
+//
+
+using System;
+
+namespace TagLib.Aac
+{
+	/// <summary>
+	///    This structure implements <see cref="IAudioCodec" /> and provides
+	///    information about an ADTS AAC audio stream.
+	/// </summary>
+	public class AudioHeader : IAudioCodec
+	{
+		#region Private Static Value Arrays
+
+		/// <summary>
+		///    Contains a sample rate table for ADTS AAC audio.
+		/// </summary>
+		static readonly int[] sample_rates = new int[13] {
+			96000, 88200, 64000, 48000, 44100, 32000,
+			24000, 22050, 16000, 12000, 11025, 8000, 7350
+		};
+
+		/// <summary>
+		///    Contains a channel table for ADTS AAC audio.
+		/// </summary>
+		static readonly int[] channels = new int[8] {
+			0, 1, 2, 3, 4, 5, 6, 8
+		};
+
+		#endregion
+
+
+
+		#region Private Properties
+
+		/// <summary>
+		///    Contains the audio stream length.
+		/// </summary>
+		long stream_length;
+
+		/// <summary>
+		///    Contains the audio stream duration.
+		/// </summary>
+		TimeSpan duration;
+
+		/// <summary>
+		///    Contains the number of channels in the audio
+		/// </summary>
+		readonly int audiochannels;
+
+		/// <summary>
+		///    Contains the bitrate of the audio stream
+		/// </summary>
+		readonly int audiobitrate;
+
+		/// <summary>
+		///    Contains the samplerate of the audio stream
+		/// </summary>
+		readonly int audiosamplerate;
+
+		#endregion
+
+
+
+		#region Public Fields
+
+		/// <summary>
+		///    An empty and unset header.
+		/// </summary>
+		public static readonly AudioHeader Unknown = new AudioHeader ();
+
+		#endregion
+
+
+
+		#region Constructors
+
+		/// <summary>
+		///    Constructs and initializes a new empty instance of <see
+		///    cref="AudioHeader" />
+		/// </summary>       
+		AudioHeader ()
+		{
+			stream_length = 0;
+			duration = TimeSpan.Zero;
+			audiochannels = 0;
+			audiobitrate = 0;
+			audiosamplerate = 0;
+		}
+
+		/// <summary>
+		///    Constructs and initializes a new instance of <see
+		///    cref="AudioHeader" /> by populating it with specified
+		///    values.
+		/// </summary>
+		/// <param name="channels">
+		///    A <see cref="int" /> value indicating the number
+		///    of channels in the audio stream
+		/// </param>
+		/// <param name="bitrate">
+		///    A <see cref="int" /> value indicating the bitrate
+		///    of  the audio stream
+		/// </param>
+		/// <param name="samplerate">
+		///    A <see cref="int" /> value indicating the samplerate
+		///    of  the audio stream
+		/// </param>
+		/// <param name="numberofsamples">
+		///    A <see cref="int" /> value indicating the number
+		///    of samples in the audio stream
+		/// </param>
+		/// <param name="numberofframes">
+		///    A <see cref="int" /> value indicating the number
+		///    of frames in the audio stream
+		/// </param>
+		AudioHeader (int channels, int bitrate, int samplerate, int numberofsamples, int numberofframes)
+		{
+			duration = TimeSpan.Zero;
+			stream_length = 0;
+			audiochannels = channels;
+			audiobitrate = bitrate;
+			audiosamplerate = samplerate;
+		}
+
+		#endregion
+
+
+
+		#region Public Properties
+
+		/// <summary>
+		///    Gets a text description of the media represented by the
+		///    current instance.
+		/// </summary>
+		/// <value>
+		///    A <see cref="string" /> object containing a description
+		///    of the media represented by the current instance.
+		/// </value>
+		public string Description {
+			get {
+				return "ADTS AAC";
+			}
+		}
+
+		/// <summary>
+		///    Gets the types of media represented by the current
+		///    instance.
+		/// </summary>
+		/// <value>
+		///    Always <see cref="MediaTypes.Audio" />.
+		/// </value>
+		public MediaTypes MediaTypes {
+			get { return MediaTypes.Audio; }
+		}
+
+		/// <summary>
+		///    Gets the duration of the media represented by the current
+		///    instance.
+		/// </summary>
+		/// <value>
+		///    A <see cref="TimeSpan" /> containing the duration of the
+		///    media represented by the current instance.
+		/// </value>
+		/// <remarks>
+		///    If <see cref="SetStreamLength" /> has not been called, this 
+		///    value will not be correct.
+		/// </remarks>
+		public TimeSpan Duration {
+			get {
+				return duration;
+			}
+		}
+
+		/// <summary>
+		///    Gets the bitrate of the audio represented by the current
+		///    instance.
+		/// </summary>
+		/// <value>
+		///    A <see cref="int" /> value containing a bitrate of the
+		///    audio represented by the current instance.
+		/// </value>
+		public int AudioBitrate {
+			get {
+				return audiobitrate;
+			}
+		}
+
+		/// <summary>
+		///    Gets the sample rate of the audio represented by the
+		///    current instance.
+		/// </summary>
+		/// <value>
+		///    A <see cref="int" /> value containing the sample rate of
+		///    the audio represented by the current instance.
+		/// </value>
+		public int AudioSampleRate {
+			get {
+				return audiosamplerate;
+			}
+		}
+
+		/// <summary>
+		///    Gets the number of channels in the audio represented by
+		///    the current instance.
+		/// </summary>
+		/// <value>
+		///    A <see cref="int" /> value containing the number of
+		///    channels in the audio represented by the current
+		///    instance.
+		/// </value>
+		public int AudioChannels {
+			get { return audiochannels; }
+		}
+
+		#endregion
+
+
+
+		#region Public Methods
+
+		/// <summary>
+		///    Sets the length of the audio stream represented by the
+		///    current instance.
+		/// </summary>
+		/// <param name="streamLength">
+		///    A <see cref="long" /> value specifying the length in
+		///    bytes of the audio stream represented by the current
+		///    instance.
+		/// </param>
+		/// <remarks>
+		///    The this value has been set, <see cref="Duration" /> will
+		///    return an incorrect value.
+		/// </remarks>
+		public void SetStreamLength (long streamLength)
+		{
+			stream_length = streamLength;
+			duration = TimeSpan.FromSeconds (stream_length * 8.0 / audiobitrate);
+		}
+
+		#endregion
+
+
+
+		#region Public Static Methods
+
+		/// <summary>
+		///    Searches for an audio header in a <see cref="TagLib.File"
+		///    /> starting at a specified position and searching through
+		///    a specified number of bytes.
+		/// </summary>
+		/// <param name="header">
+		///    A <see cref="AudioHeader" /> object in which the found
+		///    header will be stored.
+		/// </param>
+		/// <param name="file">
+		///    A <see cref="TagLib.File" /> object to search.
+		/// </param>
+		/// <param name="position">
+		///    A <see cref="long" /> value specifying the seek position
+		///    in <paramref name="file" /> at which to start searching.
+		/// </param>
+		/// <param name="length">
+		///    A <see cref="int" /> value specifying the maximum number
+		///    of bytes to search before aborting.
+		/// </param>
+		/// <returns>
+		///    A <see cref="bool" /> value indicating whether or not a
+		///    header was found.
+		/// </returns>
+		/// <exception cref="ArgumentNullException">
+		///    <paramref name="file" /> is <see langword="null" />.
+		/// </exception>
+		public static bool Find (out AudioHeader header, TagLib.File file, long position, int length)
+		{
+			if (file == null)
+				throw new ArgumentNullException (nameof (file));
+
+			long end = position + length;
+			header = Unknown;
+
+			file.Seek (position);
+
+			ByteVector buffer = file.ReadBlock (3);
+
+			if (buffer.Count < 3)
+				return false;
+
+			do {
+				file.Seek (position + 3);
+				buffer = buffer.Mid (buffer.Count - 3);
+				buffer.Add (file.ReadBlock (
+					(int)TagLib.File.BufferSize));
+
+				for (int i = 0; i < buffer.Count - 3 &&
+					(length < 0 || position + i < end); i++)
+					if (buffer[i] == 0xFF
+						&& buffer[i + 1] >= 0xF0) // 0xFFF
+						try {
+							BitStream bits = new BitStream (buffer.Mid (i, 7).Data);
+
+							// 12 bits sync header 
+							bits.ReadInt32 (12);
+
+							// 1 bit mpeg 2/4
+							bits.ReadInt32 (1);
+
+							// 2 bits layer
+							bits.ReadInt32 (2);
+
+							// 1 bit protection absent  
+							bits.ReadInt32 (1);
+
+							// 2 bits profile object type
+							bits.ReadInt32 (2);
+
+							// 4 bits sampling frequency index                            
+							int samplerateindex = bits.ReadInt32 (4);
+							if (samplerateindex >= sample_rates.Length)
+								return false;
+							long samplerate = sample_rates[samplerateindex];
+
+							// 1 bit private bit
+							bits.ReadInt32 (1);
+
+							// 3 bits channel configuration
+							int channelconfigindex = bits.ReadInt32 (3);
+							if (channelconfigindex >= channels.Length)
+								return false;
+
+							// 4 copyright bits
+							bits.ReadInt32 (4);
+
+							// 13 bits frame length
+							long framelength = bits.ReadInt32 (13); // double check framelength
+							if (framelength < 7)
+								return false;
+
+							// 11 bits buffer fullness
+							bits.ReadInt32 (11);
+
+							// 2 bits number of raw data blocks in frame
+							int numberofframes = bits.ReadInt32 (2) + 1;
+
+							long numberofsamples = numberofframes * 1024;
+							long bitrate = framelength * 8 * samplerate / numberofsamples;
+
+							header = new AudioHeader (channels[channelconfigindex],
+								(int)bitrate,
+								(int)samplerate,
+								(int)numberofsamples,
+								numberofframes);
+
+							return true;
+						} catch (CorruptFileException) {
+						}
+
+				position += TagLib.File.BufferSize;
+			} while (buffer.Count > 3 && (length < 0 || position < end));
+
+			return false;
+		}
+
+		/// <summary>
+		///    Searches for an audio header in a <see cref="TagLib.File"
+		///    /> starting at a specified position and searching to the
+		///    end of the file.
+		/// </summary>
+		/// <param name="header">
+		///    A <see cref="AudioHeader" /> object in which the found
+		///    header will be stored.
+		/// </param>
+		/// <param name="file">
+		///    A <see cref="TagLib.File" /> object to search.
+		/// </param>
+		/// <param name="position">
+		///    A <see cref="long" /> value specifying the seek position
+		///    in <paramref name="file" /> at which to start searching.
+		/// </param>
+		/// <returns>
+		///    A <see cref="bool" /> value indicating whether or not a
+		///    header was found.
+		/// </returns>
+		/// <remarks>
+		///    Searching to the end of the file can be very, very slow
+		///    especially for corrupt or non-MPEG files. It is
+		///    recommended to use <see
+		///    cref="M:AudioHeader.Find(AudioHeader,TagLib.File,long,int)" />
+		///    instead.
+		/// </remarks>
+		public static bool Find (out AudioHeader header, TagLib.File file, long position)
+		{
+			return Find (out header, file, position, -1);
+		}
+
+		#endregion
+	}
+}

Scripts/TaglibSharp/Aac/AudioHeader.cs.meta

@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: a70f4e38ac189d2389cf4717f5a1869a
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 

Scripts/TaglibSharp/Aac/BitStream.cs

@@ -0,0 +1,100 @@
+//
+// BitStream.cs: Helper to read bits from a byte array.
+//
+// Copyright (C) 2009 Patrick Dehne
+// 
+// This library is free software; you can redistribute it and/or modify
+// it  under the terms of the GNU Lesser General Public License version
+// 2.1 as published by the Free Software Foundation.
+//
+// This library is distributed in the hope that it will be useful, but
+// WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+// Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public
+// License along with this library; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
+// USA
+//
+
+using System;
+using System.Collections;
+using System.Diagnostics;
+
+namespace TagLib.Aac
+{
+	/// <summary>
+	///    This class is used to help reading arbitary number of bits from
+	///    a fixed array of bytes
+	/// </summary>
+	public class BitStream
+	{
+		readonly BitArray bits;
+		int bitindex;
+
+
+		#region Constructors
+
+		/// <summary>
+		///    Construct a new <see cref="BitStream"/>.
+		/// </summary>
+		/// <param name="buffer">
+		///    A <see cref="T:System.Byte[]"/>, must be 7 bytes long.
+		/// </param>
+		public BitStream (byte[] buffer)
+		{
+			Debug.Assert (buffer.Length == 7, "buffer.Length == 7", "buffer size invalid");
+
+			if (buffer.Length != 7)
+				throw new ArgumentException ("Buffer size must be 7 bytes");
+
+			// Reverse bits            
+			bits = new BitArray (buffer.Length * 8);
+			for (int i = 0; i < buffer.Length; i++) {
+				for (int y = 0; y < 8; y++) {
+					bits[i * 8 + y] = ((buffer[i] & (1 << (7 - y))) > 0);
+				}
+			}
+
+			bitindex = 0;
+		}
+
+		#endregion
+
+
+
+		#region Public Methods
+
+		/// <summary>
+		///    Reads an Int32 from the bitstream        
+		/// </summary>
+		/// <param name="numberOfBits">
+		///    A <see cref="int" /> value containing the number
+		///    of bits to read from the bitstream
+		/// </param>
+		public int ReadInt32 (int numberOfBits)
+		{
+			Debug.Assert (numberOfBits > 0, "numberOfBits < 1");
+			Debug.Assert (numberOfBits <= 32, "numberOfBits <= 32");
+
+			if (numberOfBits <= 0)
+				throw new ArgumentException ("Number of bits to read must be >= 1");
+
+			if (numberOfBits > 32)
+				throw new ArgumentException ("Number of bits to read must be <= 32");
+
+			int value = 0;
+			int start = bitindex + numberOfBits - 1;
+			for (int i = 0; i < numberOfBits; i++) {
+				value += bits[start] ? (1 << i) : 0;
+				bitindex++;
+				start--;
+			}
+
+			return value;
+		}
+
+		#endregion
+	}
+}

Scripts/TaglibSharp/Aac/BitStream.cs.meta

@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: 8284bad068f4283f29df4c52751a79cc
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 

Scripts/TaglibSharp/Aac/File.cs

@@ -0,0 +1,272 @@
+//
+// File.cs: Provides tagging and properties support for ADTS AAC files
+//
+// Here is the ADTS Header description used for implementation:
+// http://www.hydrogenaudio.org/forums/lofiversion/index.php/t21617.html
+//
+// Copyright (C) 2009 Patrick Dehne
+// 
+// This library is free software; you can redistribute it and/or modify
+// it  under the terms of the GNU Lesser General Public License version
+// 2.1 as published by the Free Software Foundation.
+//
+// This library is distributed in the hope that it will be useful, but
+// WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+// Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public
+// License along with this library; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
+// USA
+//
+
+using System;
+
+namespace TagLib.Aac
+{
+	/// <summary>
+	///    This class extends <see cref="TagLib.NonContainer.File" /> to
+	///    provide tagging and properties support for ADTS AAC audio files.
+	/// </summary>
+	/// <remarks>
+	///    A <see cref="TagLib.Id3v1.Tag" /> and <see
+	///    cref="TagLib.Id3v2.Tag" /> will be added automatically to any
+	///    file that doesn't contain one. This change does not effect the
+	///    file until it is saved and can be reversed using the following
+	///    method:
+	///    <code>file.RemoveTags (file.TagTypes &amp; ~file.TagTypesOnDisk);</code>
+	/// </remarks>
+	[SupportedMimeType ("taglib/aac", "aac")]
+	[SupportedMimeType ("audio/aac")]
+	public class File : TagLib.NonContainer.File
+	{
+		#region Private Fields
+
+		/// <summary>
+		///    Contains the first audio header.
+		/// </summary>
+		AudioHeader first_header;
+
+		#endregion
+
+
+
+		#region Constructors
+
+		/// <summary>
+		///    Constructs and initializes a new instance of <see
+		///    cref="File" /> for a specified path in the local
+		///    file system and specified read style.
+		/// </summary>
+		/// <param name="path">
+		///    A <see cref="string" /> object containing the path of the
+		///    file to use in the new instance.
+		/// </param>
+		/// <param name="propertiesStyle">
+		///    A <see cref="ReadStyle" /> value specifying at what level
+		///    of accuracy to read the media properties, or <see
+		///    cref="ReadStyle.None" /> to ignore the properties.
+		/// </param>
+		/// <exception cref="ArgumentNullException">
+		///    <paramref name="path" /> is <see langword="null" />.
+		/// </exception>
+		public File (string path, ReadStyle propertiesStyle)
+			: base (path, propertiesStyle)
+		{
+		}
+
+		/// <summary>
+		///    Constructs and initializes a new instance of <see
+		///    cref="File" /> for a specified path in the local
+		///    file system with an average read style.
+		/// </summary>
+		/// <param name="path">
+		///    A <see cref="string" /> object containing the path of the
+		///    file to use in the new instance.
+		/// </param>
+		/// <exception cref="ArgumentNullException">
+		///    <paramref name="path" /> is <see langword="null" />.
+		/// </exception>
+		public File (string path) : base (path)
+		{
+		}
+
+		/// <summary>
+		///    Constructs and initializes a new instance of <see
+		///    cref="File" /> for a specified file abstraction and
+		///    specified read style.
+		/// </summary>
+		/// <param name="abstraction">
+		///    A <see cref="TagLib.File.IFileAbstraction" /> object to use when
+		///    reading from and writing to the file.
+		/// </param>
+		/// <param name="propertiesStyle">
+		///    A <see cref="ReadStyle" /> value specifying at what level
+		///    of accuracy to read the media properties, or <see
+		///    cref="ReadStyle.None" /> to ignore the properties.
+		/// </param>
+		/// <exception cref="ArgumentNullException">
+		///    <paramref name="abstraction" /> is <see langword="null"
+		///    />.
+		/// </exception>
+		public File (IFileAbstraction abstraction, ReadStyle propertiesStyle)
+			: base (abstraction, propertiesStyle)
+		{
+		}
+
+		/// <summary>
+		///    Constructs and initializes a new instance of <see
+		///    cref="File" /> for a specified file abstraction with
+		///    an average read style.
+		/// </summary>
+		/// <param name="abstraction">
+		///    A <see cref="TagLib.File.IFileAbstraction" /> object to use when
+		///    reading from and writing to the file.
+		/// </param>
+		/// <exception cref="ArgumentNullException">
+		///    <paramref name="abstraction" /> is <see langword="null"
+		///    />.
+		/// </exception>
+		public File (IFileAbstraction abstraction)
+			: base (abstraction)
+		{
+		}
+
+		#endregion
+
+
+
+		#region Public Methods
+
+		/// <summary>
+		///    Gets a tag of a specified type from the current instance,
+		///    optionally creating a new tag if possible.
+		/// </summary>
+		/// <param name="type">
+		///    A <see cref="TagLib.TagTypes" /> value indicating the
+		///    type of tag to read.
+		/// </param>
+		/// <param name="create">
+		///    A <see cref="bool" /> value specifying whether or not to
+		///    try and create the tag if one is not found.
+		/// </param>
+		/// <returns>
+		///    A <see cref="Tag" /> object containing the tag that was
+		///    found in or added to the current instance. If no
+		///    matching tag was found and none was created, <see
+		///    langword="null" /> is returned.
+		/// </returns>
+		/// <remarks>
+		///    If a <see cref="TagLib.Id3v2.Tag" /> is added to the
+		///    current instance, it will be placed at the start of the
+		///    file. On the other hand, <see cref="TagLib.Id3v1.Tag" />
+		///    <see cref="TagLib.Ape.Tag" /> will be added to the end of
+		///    the file. All other tag types will be ignored.
+		/// </remarks>
+		public override Tag GetTag (TagTypes type, bool create)
+		{
+			Tag t = (Tag as TagLib.NonContainer.Tag).GetTag (type);
+
+			if (t != null || !create)
+				return t;
+
+			switch (type) {
+			case TagTypes.Id3v1:
+				return EndTag.AddTag (type, Tag);
+
+			case TagTypes.Id3v2:
+				return StartTag.AddTag (type, Tag);
+
+			case TagTypes.Ape:
+				return EndTag.AddTag (type, Tag);
+
+			default:
+				return null;
+			}
+		}
+
+		#endregion
+
+
+
+		#region Protected Methods
+
+		/// <summary>
+		///    Reads format specific information at the start of the
+		///    file.
+		/// </summary>
+		/// <param name="start">
+		///    A <see cref="long" /> value containing the seek position
+		///    at which the tags end and the media data begins.
+		/// </param>
+		/// <param name="propertiesStyle">
+		///    A <see cref="ReadStyle" /> value specifying at what level
+		///    of accuracy to read the media properties, or <see
+		///    cref="ReadStyle.None" /> to ignore the properties.
+		/// </param>
+		/// <remarks>
+		///    This method only searches for an audio header in the
+		///    first 16384 bytes of code to avoid searching forever in
+		///    corrupt files.
+		/// </remarks>
+		protected override void ReadStart (long start, ReadStyle propertiesStyle)
+		{
+			// Only check the first 16 bytes so we're not stuck
+			// reading a bad file forever.
+			if ((propertiesStyle & ReadStyle.Average) != 0 &&
+				!AudioHeader.Find (out first_header, this, start, 0x4000))
+				throw new CorruptFileException ("ADTS audio header not found.");
+		}
+
+		/// <summary>
+		///    Reads format specific information at the end of the
+		///    file.
+		/// </summary>
+		/// <param name="end">
+		///    A <see cref="long" /> value containing the seek position
+		///    at which the media data ends and the tags begin.
+		/// </param>
+		/// <param name="propertiesStyle">
+		///    A <see cref="ReadStyle" /> value specifying at what level
+		///    of accuracy to read the media properties, or <see
+		///    cref="ReadStyle.None" /> to ignore the properties.
+		/// </param>
+		protected override void ReadEnd (long end, ReadStyle propertiesStyle)
+		{
+			// Make sure we have ID3v1 and ID3v2 tags.
+			GetTag (TagTypes.Id3v1, true);
+			GetTag (TagTypes.Id3v2, true);
+		}
+
+		/// <summary>
+		///    Reads the audio properties from the file represented by
+		///    the current instance.
+		/// </summary>
+		/// <param name="start">
+		///    A <see cref="long" /> value containing the seek position
+		///    at which the tags end and the media data begins.
+		/// </param>
+		/// <param name="end">
+		///    A <see cref="long" /> value containing the seek position
+		///    at which the media data ends and the tags begin.
+		/// </param>
+		/// <param name="propertiesStyle">
+		///    A <see cref="ReadStyle" /> value specifying at what level
+		///    of accuracy to read the media properties, or <see
+		///    cref="ReadStyle.None" /> to ignore the properties.
+		/// </param>
+		/// <returns>
+		///    A <see cref="TagLib.Properties" /> object describing the
+		///    media properties of the file represented by the current
+		///    instance.
+		/// </returns>
+		protected override Properties ReadProperties (long start, long end, ReadStyle propertiesStyle)
+		{
+			first_header.SetStreamLength (end - start);
+			return new Properties (TimeSpan.Zero, first_header);
+		}
+
+		#endregion
+	}
+}

Scripts/TaglibSharp/Aac/File.cs.meta

@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: 5ea5a2b9978c53a708489187d4f05f90
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: