95 lines
2.6 KiB
Java
95 lines
2.6 KiB
Java
//******************************************************************************
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//
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// File: fdATCompressor.java
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// Package: edu.rit.image.png
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// Unit: Class edu.rit.image.png.fdATCompressor
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//
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// This Java source file is copyright (C) 2013 by Alan Kaminsky. All rights
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// reserved. For further information, contact the author, Alan Kaminsky, at
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// ark@cs.rit.edu.
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//
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// This Java source file is part of the Parallel Java 2 Library ("PJ2"). PJ2 is
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// free software; you can redistribute it and/or modify it under the terms of
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// the GNU General Public License as published by the Free Software Foundation;
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// either version 3 of the License, or (at your option) any later version.
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//
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// PJ2 is distributed in the hope that it will be useful, but WITHOUT ANY
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// WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
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// A PARTICULAR PURPOSE. See the GNU General Public License for more details.
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//
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// A copy of the GNU General Public License is provided in the file gpl.txt. You
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// may also obtain a copy of the GNU General Public License on the World Wide
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// Web at http://www.gnu.org/licenses/gpl.html.
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//
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//******************************************************************************
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package edu.rit.image.png;
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/**
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* Class fdATCompressor provides an object that compresses a sequence of bytes
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* into APNG fdAT chunks and writes the chunks to a {@linkplain ChunkOutput}
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* object.
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*
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* @author Alan Kaminsky
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* @version 01-Jul-2013
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*/
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public class fdATCompressor
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extends Compressor
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{
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// Exported constructors.
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/**
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* Construct a new fdAT compressor that will write to the given underlying
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* chunk output object.
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*
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* @param chunkOutput Chunk output object.
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* @param seqnum Initial chunk sequence number.
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*
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* @exception NullPointerException
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* (unchecked exception) Thrown if <TT>chunkOutput</TT> is null.
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*/
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public fdATCompressor
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(ChunkOutput chunkOutput,
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int seqnum)
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{
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super (chunkOutput, seqnum);
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}
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// Hidden operations.
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/**
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* Get a PNG chunk of the proper type containing the given compressed data.
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*
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* @param seqnum Chunk sequence number.
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* @param data Compressed data buffer.
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* @param off Index of first data byte.
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* @param len Number of data bytes.
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*
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* @return Chunk.
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*/
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Chunk getChunk
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(int seqnum,
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byte[] data,
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int off,
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int len)
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{
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return new fdATChunk (seqnum, data, off, len);
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}
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/**
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* Increment the given sequence number, if required by this compressor's
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* chunk type.
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*
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* @param seqnum Chunk sequence number.
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*
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* @return Chunk sequence number after incrementing.
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*/
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int incrementSeqnum
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(int seqnum)
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{
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return seqnum + 1;
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}
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}
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