jellyfin/Emby.Common.Implementations/TextEncoding/UniversalDetector/Core/BitPackage.cs
2017-04-18 01:53:39 -04:00

99 lines
3.7 KiB
C#

/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is Mozilla Universal charset detector code.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 2001
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Kohei TAKETA <k-tak@void.in> (Java port)
* Rudi Pettazzi <rudi.pettazzi@gmail.com> (C# port)
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
namespace UniversalDetector.Core
{
public class BitPackage
{
public static int INDEX_SHIFT_4BITS = 3;
public static int INDEX_SHIFT_8BITS = 2;
public static int INDEX_SHIFT_16BITS = 1;
public static int SHIFT_MASK_4BITS = 7;
public static int SHIFT_MASK_8BITS = 3;
public static int SHIFT_MASK_16BITS = 1;
public static int BIT_SHIFT_4BITS = 2;
public static int BIT_SHIFT_8BITS = 3;
public static int BIT_SHIFT_16BITS = 4;
public static int UNIT_MASK_4BITS = 0x0000000F;
public static int UNIT_MASK_8BITS = 0x000000FF;
public static int UNIT_MASK_16BITS = 0x0000FFFF;
private int indexShift;
private int shiftMask;
private int bitShift;
private int unitMask;
private int[] data;
public BitPackage(int indexShift, int shiftMask,
int bitShift, int unitMask, int[] data)
{
this.indexShift = indexShift;
this.shiftMask = shiftMask;
this.bitShift = bitShift;
this.unitMask = unitMask;
this.data = data;
}
public static int Pack16bits(int a, int b)
{
return ((b << 16) | a);
}
public static int Pack8bits(int a, int b, int c, int d)
{
return Pack16bits((b << 8) | a, (d << 8) | c);
}
public static int Pack4bits(int a, int b, int c, int d,
int e, int f, int g, int h)
{
return Pack8bits((b << 4) | a, (d << 4) | c,
(f << 4) | e, (h << 4) | g);
}
public int Unpack(int i)
{
return (data[i >> indexShift] >>
((i & shiftMask) << bitShift)) & unitMask;
}
}
}