gnu.javax.imageio.jpeg

Class HuffmanTable


public class HuffmanTable
extends Object

This Object construct a JPEGHuffmanTable which can be used to encode/decode a scan from a JPEG codec stream. The table must be initalized with either a BITS byte amount and a Huffman Table Value for decoding or a Huffman Size and Huffman Code table for encoding.

Field Summary

static int
HUFFMAN_MAX_TABLES

Constructor Summary

HuffmanTable(JPEGHuffmanTable table)

Method Summary

int
decode(JPEGImageInputStream JPEGStream)
Generated from FIGURE F.16 - Procedure for DECODE on ISO DIS 10918-1.
static int
extend(int diff, int t)
Generated from FIGURE F.12 - Extending the sign bit of a decoded value in on ISO DIS 10918-1.
void
orderCodes(boolean isDC)
Generated from FIGURE C.3 - Generation of Order Codes and tables EHUFCO and EHUFSI from the ISO DIS 10918-1.

Methods inherited from class java.lang.Object

clone, equals, extends Object> getClass, finalize, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

HUFFMAN_MAX_TABLES

public static final int HUFFMAN_MAX_TABLES
Field Value:
4

Constructor Details

HuffmanTable

public HuffmanTable(JPEGHuffmanTable table)

Method Details

decode

public int decode(JPEGImageInputStream JPEGStream)
            throws IOException,
                   JPEGException
Generated from FIGURE F.16 - Procedure for DECODE on ISO DIS 10918-1. Requirements and Guidelines

This function takes in a dynamic amount of bits and using the Huffman table returns information on how many bits must be read in to a byte in order to reconstruct said byte.

Parameters:
JPEGStream - the bits of the data stream.

extend

public static int extend(int diff,
                         int t)
Generated from FIGURE F.12 - Extending the sign bit of a decoded value in on ISO DIS 10918-1. Requirements and Guidelines

Parameters:
diff - TODO
t - TODO
Returns:
TODO

orderCodes

public void orderCodes(boolean isDC)
Generated from FIGURE C.3 - Generation of Order Codes and tables EHUFCO and EHUFSI from the ISO DIS 10918-1. Requirements and Guidelines

HuffmanTable.java -- Copyright (C) 2006 Free Software Foundation, Inc. This file is part of GNU Classpath. GNU Classpath is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version. GNU Classpath 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 General Public License for more details. You should have received a copy of the GNU General Public License along with GNU Classpath; see the file COPYING. If not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. Linking this library statically or dynamically with other modules is making a combined work based on this library. Thus, the terms and conditions of the GNU General Public License cover the whole combination. As a special exception, the copyright holders of this library give you permission to link this library with independent modules to produce an executable, regardless of the license terms of these independent modules, and to copy and distribute the resulting executable under terms of your choice, provided that you also meet, for each linked independent module, the terms and conditions of the license of that module. An independent module is a module which is not derived from or based on this library. If you modify this library, you may extend this exception to your version of the library, but you are not obligated to do so. If you do not wish to do so, delete this exception statement from your version.