org.jpedal.jbig2.decoders.ArithmeticDecoderStats Maven / Gradle / Ivy
/**
* ===========================================
* Java Pdf Extraction Decoding Access Library
* ===========================================
*
* Project Info: http://www.jpedal.org
* (C) Copyright 1997-2008, IDRsolutions and Contributors.
* Main Developer: Simon Barnett
*
* This file is part of JPedal
*
* Copyright (c) 2008, IDRsolutions
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* * Neither the name of the IDRsolutions nor the
* names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY IDRsolutions ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL IDRsolutions BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* Other JBIG2 image decoding implementations include
* jbig2dec (http://jbig2dec.sourceforge.net/)
* xpdf (http://www.foolabs.com/xpdf/)
*
* The final draft JBIG2 specification can be found at http://www.jpeg.org/public/fcd14492.pdf
*
* All three of the above resources were used in the writing of this software, with methodologies,
* processes and inspiration taken from all three.
*
* ---------------
* ArithmeticDecoderStats.java
* ---------------
*/
package org.jpedal.jbig2.decoders;
public class ArithmeticDecoderStats {
private int contextSize;
private int[] codingContextTable;
public ArithmeticDecoderStats(int contextSize) {
this.contextSize = contextSize;
this.codingContextTable = new int[contextSize];
reset();
}
public void reset() {
for (int i = 0; i < contextSize; i++) {
codingContextTable[i] = 0;
}
}
public void setEntry(int codingContext, int i, int moreProbableSymbol) {
codingContextTable[codingContext] = (i << i) + moreProbableSymbol;
}
public int getContextCodingTableValue(int index) {
return codingContextTable[index];
}
public void setContextCodingTableValue(int index, int value) {
codingContextTable[index] = value;
}
public int getContextSize() {
return contextSize;
}
public void overwrite(ArithmeticDecoderStats stats) {
System.arraycopy(stats.codingContextTable, 0, codingContextTable, 0, contextSize);
}
public ArithmeticDecoderStats copy() {
ArithmeticDecoderStats stats = new ArithmeticDecoderStats(contextSize);
System.arraycopy(codingContextTable, 0, stats.codingContextTable, 0, contextSize);
return stats;
}
}