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Former-commit-id: 906a47f0606c8831f526bab4d0408651e9052a9e Former-commit-id: 4c760c7eb123df7ea1d2dd5d15a5b6b4a6d8383c Former-commit-id: 4c431f1e32cd5aa5304c7da88a68fc4a850d860baf/merge-core
James Jackson-South
11 years ago
20 changed files with 527 additions and 412 deletions
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// --------------------------------------------------------------------------------------------------------------------
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// <copyright file="BitEncoder.cs" company="James South">
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// Copyright © James South and contributors.
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// Licensed under the Apache License, Version 2.0.
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// </copyright>
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// <summary>
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// Handles the encoding of bits for compression.
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// </summary>
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// --------------------------------------------------------------------------------------------------------------------
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namespace ImageProcessor.Formats |
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{ |
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using System.Collections.Generic; |
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/// <summary>
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/// Handles the encoding of bits for compression.
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/// </summary>
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internal class BitEncoder |
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{ |
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/// <summary>
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/// The current working bit.
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/// </summary>
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private int currentBit; |
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/// <summary>
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/// The current value.
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/// </summary>
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private int currentValue; |
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/// <summary>
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/// The inner list for collecting the bits.
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/// </summary>
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private readonly List<byte> list = new List<byte>(); |
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/// <summary>
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/// The number of bytes in the encoder.
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/// </summary>
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internal int Length => this.list.Count; |
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/// <summary>
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/// Gets or sets the intitial bit.
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/// </summary>
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public int IntitialBit { get; set; } |
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/// <summary>
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/// Initializes a new instance of the <see cref="BitEncoder"/> class.
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/// </summary>
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/// <param name="initial">
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/// The initial bits.
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/// </param>
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public BitEncoder(int initial) |
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{ |
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this.IntitialBit = initial; |
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} |
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/// <summary>
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/// Adds the current byte to the end of the encoder.
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/// </summary>
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/// <param name="item">
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/// The byte to add.
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/// </param>
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public void Add(int item) |
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{ |
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this.currentValue |= item << this.currentBit; |
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this.currentBit += this.IntitialBit; |
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while (this.currentBit >= 8) |
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{ |
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byte value = (byte)(this.currentValue & 0XFF); |
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this.currentValue = this.currentValue >> 8; |
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this.currentBit -= 8; |
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this.list.Add(value); |
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} |
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} |
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/// <summary>
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/// Adds the collection of bytes to the end of the encoder.
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/// </summary>
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/// <param name="collection">
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/// The collection of bytes to add.
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/// The collection itself cannot be null but can contain elements that are null.</param>
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public void AddRange(byte[] collection) |
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{ |
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this.list.AddRange(collection); |
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} |
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/// <summary>
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/// The end.
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/// </summary>
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internal void End() |
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{ |
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while (this.currentBit > 0) |
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{ |
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byte value = (byte)(this.currentValue & 0XFF); |
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this.currentValue = this.currentValue >> 8; |
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this.currentBit -= 8; |
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this.list.Add(value); |
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} |
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} |
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/// <summary>
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/// Copies a range of elements from the encoder to a compatible one-dimensional array,
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/// starting at the specified index of the target array.
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/// </summary>
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/// <param name="index">
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/// The zero-based index in the source <see cref="BitEncoder"/> at which copying begins.
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/// </param>
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/// <param name="array">
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/// The one-dimensional Array that is the destination of the elements copied
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/// from <see cref="BitEncoder"/>. The Array must have zero-based indexing
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/// </param>
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/// <param name="arrayIndex">The zero-based index in array at which copying begins.</param>
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/// <param name="count">The number of bytes to copy.</param>
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public void CopyTo(int index, byte[] array, int arrayIndex, int count) |
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{ |
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this.list.CopyTo(index, array, arrayIndex, count); |
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} |
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/// <summary>
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/// Removes all the bytes from the encoder.
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/// </summary>
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public void Clear() |
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{ |
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this.list.Clear(); |
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} |
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/// <summary>
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/// Copies the bytes into a new array.
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/// </summary>
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/// <returns><see cref="T:byte[]"/></returns>
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public byte[] ToArray() |
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{ |
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return this.list.ToArray(); |
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} |
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} |
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} |
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@ -1,4 +1,5 @@ |
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<?xml version="1.0" encoding="utf-8"?> |
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<packages> |
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<package id="SharpZipLib.Portable" version="0.86.0.0002" targetFramework="portable-net45+win+wp80" /> |
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<package id="SharpZipLib.Portable" version="0.86.0.0002" targetFramework="portable-net45+win8+wp8" /> |
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<package id="StyleCop.Analyzers" version="1.0.0-beta013" targetFramework="portable45-net45+win8+wp8" developmentDependency="true" /> |
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</packages> |
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@ -0,0 +1 @@ |
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98e8f0bd9cd631e784bcc356a589d87989d43176 |
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