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/*
* JPEGHuffmanTable
*
* Copyright (c) 2005, 2006 Marco Schmidt.
* All rights reserved.
*/
package net.sourceforge.jiu.codecs.jpeg;
/**
* Data class that stores a single Huffman table, including class
* (AC or DC), ID and codes for the 16 possible bit lengths from 1 to 16.
* @author Marco Schmidt
* @since 0.13.0
*/
public class JPEGHuffmanTable
{
public static final int TABLE_CLASS_AC = 1;
public static final int TABLE_CLASS_DC = 0;
private int id;
private int classAcDc;
private int[][] codes;
private int[] huffCode;
private int[] huffSize;
private int lastK;
public void createDecoderTables()
{
generateSizeTable();
generateCodeTable();
// TODO: F.15
}
/**
* Initialize huffCode from huffSize.
* P&M figure C.2, p. 406f.
*/
private void generateCodeTable()
{
huffCode = new int[257];
int k = 0;
int code = 0;
int si = huffSize[0];
while (true)
{
while (true)
{
huffCode[k] = code;
code++;
k++;
if (huffSize[k] != si)
{
break;
}
}
if (huffSize[k] == 0)
{
break;
}
while (true)
{
code <<= 1;
si++;
if (huffSize[k] == si)
{
break;
}
}
}
}
/**
* Initialize huffSize and lastK from codes.
* P&M figure C.1, p. 405f.
*/
private void generateSizeTable()
{
huffSize = new int[257];
int i = 1;
int j = 1;
int k = 0;
while (true)
{
while (true)
{
if (j > codes[i].length)
{
break;
}
huffSize[k] = i;
k++;
j++;
}
i++;
j = 1;
if (i > JPEGConstants.MAX_HUFFMAN_CODE_LENGTH)
{
break;
}
}
huffSize[k] = 0;
lastK = k;
}
public int getClassAcDc()
{
return classAcDc;
}
public int[][] getCodes()
{
return codes;
}
public int getId()
{
return id;
}
public void setClassAcDc(int i)
{
classAcDc = i;
}
public void setCodes(int[][] is)
{
codes = is;
}
public void setId(int i)
{
id = i;
}
public String toString()
{
StringBuffer sb = new StringBuffer();
sb.append("id=");
sb.append(id);
sb.append("/class=");
sb.append(classAcDc == TABLE_CLASS_AC ? "AC" : "DC");
if (codes != null)
{
sb.append("/codes(length,number)=");
for (int i = 0; i < codes.length; i++)
{
if (codes[i].length > 0)
{
sb.append(" ");
sb.append((i+1));
sb.append(":");
sb.append(codes[i].length);
}
}
}
return sb.toString();
}
}
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