/**
* ===========================================
* 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.
*
* ---------------
* JBIG2StreamDecoder.java
* ---------------
*/
package org.jpedal.jbig2.decoders;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Iterator;
import java.util.List;
import org.jpedal.jbig2.JBIG2Exception;
import org.jpedal.jbig2.image.JBIG2Bitmap;
import org.jpedal.jbig2.io.StreamReader;
import org.jpedal.jbig2.segment.Segment;
import org.jpedal.jbig2.segment.SegmentHeader;
import org.jpedal.jbig2.segment.extensions.ExtensionSegment;
import org.jpedal.jbig2.segment.pageinformation.PageInformationSegment;
import org.jpedal.jbig2.segment.pattern.PatternDictionarySegment;
import org.jpedal.jbig2.segment.region.generic.GenericRegionSegment;
import org.jpedal.jbig2.segment.region.halftone.HalftoneRegionSegment;
import org.jpedal.jbig2.segment.region.refinement.RefinementRegionSegment;
import org.jpedal.jbig2.segment.region.text.TextRegionSegment;
import org.jpedal.jbig2.segment.stripes.EndOfStripeSegment;
import org.jpedal.jbig2.segment.symboldictionary.SymbolDictionarySegment;
import org.jpedal.jbig2.util.BinaryOperation;
public class JBIG2StreamDecoder {
private StreamReader reader;
private boolean noOfPagesKnown;
private boolean randomAccessOrganisation;
private int noOfPages = -1;
private List segments = new ArrayList();
private List bitmaps = new ArrayList();
private byte[] globalData;
private ArithmeticDecoder arithmeticDecoder;
private HuffmanDecoder huffmanDecoder;
private MMRDecoder mmrDecoder;
public static boolean debug = false;
public void movePointer(int i){
reader.movePointer(i);
}
public void setGlobalData(byte[] data) {
globalData = data;
}
public void decodeJBIG2(byte[] data) throws IOException, JBIG2Exception {
reader = new StreamReader(data);
resetDecoder();
boolean validFile = checkHeader();
if (JBIG2StreamDecoder.debug)
System.out.println("validFile = " + validFile);
if (!validFile) {
/**
* Assume this is a stream from a PDF so there is no file header,
* end of page segments, or end of file segments. Organisation must
* be sequential, and the number of pages is assumed to be 1.
*/
noOfPagesKnown = true;
randomAccessOrganisation = false;
noOfPages = 1;
/** check to see if there is any global data to be read */
if (globalData != null) {
/** set the reader to read from the global data */
reader = new StreamReader(globalData);
huffmanDecoder = new HuffmanDecoder(reader);
mmrDecoder = new MMRDecoder(reader);
arithmeticDecoder = new ArithmeticDecoder(reader);
/** read in the global data segments */
readSegments();
/** set the reader back to the main data */
reader = new StreamReader(data);
} else {
/**
* There's no global data, so move the file pointer back to the
* start of the stream
*/
reader.movePointer(-8);
}
} else {
/**
* We have the file header, so assume it is a valid stand-alone
* file.
*/
if (JBIG2StreamDecoder.debug)
System.out.println("==== File Header ====");
setFileHeaderFlags();
if (JBIG2StreamDecoder.debug) {
System.out.println("randomAccessOrganisation = " + randomAccessOrganisation);
System.out.println("noOfPagesKnown = " + noOfPagesKnown);
}
if (noOfPagesKnown) {
noOfPages = getNoOfPages();
if (JBIG2StreamDecoder.debug)
System.out.println("noOfPages = " + noOfPages);
}
}
huffmanDecoder = new HuffmanDecoder(reader);
mmrDecoder = new MMRDecoder(reader);
arithmeticDecoder = new ArithmeticDecoder(reader);
/** read in the main segment data */
readSegments();
}
public HuffmanDecoder getHuffmanDecoder() {
return huffmanDecoder;
}
public MMRDecoder getMMRDecoder() {
return mmrDecoder;
}
public ArithmeticDecoder getArithmeticDecoder() {
return arithmeticDecoder;
}
private void resetDecoder() {
noOfPagesKnown = false;
randomAccessOrganisation = false;
noOfPages = -1;
segments.clear();
bitmaps.clear();
}
private void readSegments() throws IOException, JBIG2Exception {
if (JBIG2StreamDecoder.debug)
System.out.println("==== Segments ====");
boolean finished = false;
while (!reader.isFinished() && !finished) {
SegmentHeader segmentHeader = new SegmentHeader();
if (JBIG2StreamDecoder.debug)
System.out.println("==== Segment Header ====");
readSegmentHeader(segmentHeader);
// read the Segment data
Segment segment = null;
int segmentType = segmentHeader.getSegmentType();
int[] referredToSegments = segmentHeader.getReferredToSegments();
int noOfReferredToSegments = segmentHeader.getReferredToSegmentCount();
switch (segmentType) {
case Segment.SYMBOL_DICTIONARY:
if (JBIG2StreamDecoder.debug)
System.out.println("==== Segment Symbol Dictionary ====");
segment = new SymbolDictionarySegment(this);
segment.setSegmentHeader(segmentHeader);
break;
case Segment.INTERMEDIATE_TEXT_REGION:
if (JBIG2StreamDecoder.debug)
System.out.println("==== Intermediate Text Region ====");
segment = new TextRegionSegment(this, false);
segment.setSegmentHeader(segmentHeader);
break;
case Segment.IMMEDIATE_TEXT_REGION:
if (JBIG2StreamDecoder.debug)
System.out.println("==== Immediate Text Region ====");
segment = new TextRegionSegment(this, true);
segment.setSegmentHeader(segmentHeader);
break;
case Segment.IMMEDIATE_LOSSLESS_TEXT_REGION:
if (JBIG2StreamDecoder.debug)
System.out.println("==== Immediate Lossless Text Region ====");
segment = new TextRegionSegment(this, true);
segment.setSegmentHeader(segmentHeader);
break;
case Segment.PATTERN_DICTIONARY:
if (JBIG2StreamDecoder.debug)
System.out.println("==== Pattern Dictionary ====");
segment = new PatternDictionarySegment(this);
segment.setSegmentHeader(segmentHeader);
break;
case Segment.INTERMEDIATE_HALFTONE_REGION:
if (JBIG2StreamDecoder.debug)
System.out.println("==== Intermediate Halftone Region ====");
segment = new HalftoneRegionSegment(this, false);
segment.setSegmentHeader(segmentHeader);
break;
case Segment.IMMEDIATE_HALFTONE_REGION:
if (JBIG2StreamDecoder.debug)
System.out.println("==== Immediate Halftone Region ====");
segment = new HalftoneRegionSegment(this, true);
segment.setSegmentHeader(segmentHeader);
break;
case Segment.IMMEDIATE_LOSSLESS_HALFTONE_REGION:
if (JBIG2StreamDecoder.debug)
System.out.println("==== Immediate Lossless Halftone Region ====");
segment = new HalftoneRegionSegment(this, true);
segment.setSegmentHeader(segmentHeader);
break;
case Segment.INTERMEDIATE_GENERIC_REGION:
if (JBIG2StreamDecoder.debug)
System.out.println("==== Intermediate Generic Region ====");
segment = new GenericRegionSegment(this, false);
segment.setSegmentHeader(segmentHeader);
break;
case Segment.IMMEDIATE_GENERIC_REGION:
if (JBIG2StreamDecoder.debug)
System.out.println("==== Immediate Generic Region ====");
segment = new GenericRegionSegment(this, true);
segment.setSegmentHeader(segmentHeader);
break;
case Segment.IMMEDIATE_LOSSLESS_GENERIC_REGION:
if (JBIG2StreamDecoder.debug)
System.out.println("==== Immediate Lossless Generic Region ====");
segment = new GenericRegionSegment(this, true);
segment.setSegmentHeader(segmentHeader);
break;
case Segment.INTERMEDIATE_GENERIC_REFINEMENT_REGION:
if (JBIG2StreamDecoder.debug)
System.out.println("==== Intermediate Generic Refinement Region ====");
segment = new RefinementRegionSegment(this, false, referredToSegments, noOfReferredToSegments);
segment.setSegmentHeader(segmentHeader);
break;
case Segment.IMMEDIATE_GENERIC_REFINEMENT_REGION:
if (JBIG2StreamDecoder.debug)
System.out.println("==== Immediate Generic Refinement Region ====");
segment = new RefinementRegionSegment(this, true, referredToSegments, noOfReferredToSegments);
segment.setSegmentHeader(segmentHeader);
break;
case Segment.IMMEDIATE_LOSSLESS_GENERIC_REFINEMENT_REGION:
if (JBIG2StreamDecoder.debug)
System.out.println("==== Immediate lossless Generic Refinement Region ====");
segment = new RefinementRegionSegment(this, true, referredToSegments, noOfReferredToSegments);
segment.setSegmentHeader(segmentHeader);
break;
case Segment.PAGE_INFORMATION:
if (JBIG2StreamDecoder.debug)
System.out.println("==== Page Information Dictionary ====");
segment = new PageInformationSegment(this);
segment.setSegmentHeader(segmentHeader);
break;
case Segment.END_OF_PAGE:
continue;
case Segment.END_OF_STRIPE:
if (JBIG2StreamDecoder.debug)
System.out.println("==== End of Stripes ====");
segment = new EndOfStripeSegment(this);
segment.setSegmentHeader(segmentHeader);
break;
case Segment.END_OF_FILE:
if (JBIG2StreamDecoder.debug)
System.out.println("==== End of File ====");
finished = true;
continue;
case Segment.PROFILES:
if (JBIG2StreamDecoder.debug)
System.out.println("PROFILES UNIMPLEMENTED");
break;
case Segment.TABLES:
if (JBIG2StreamDecoder.debug)
System.out.println("TABLES UNIMPLEMENTED");
break;
case Segment.EXTENSION:
if (JBIG2StreamDecoder.debug)
System.out.println("==== Extensions ====");
segment = new ExtensionSegment(this);
segment.setSegmentHeader(segmentHeader);
break;
default:
System.out.println("Unknown Segment type in JBIG2 stream");
break;
}
if (!randomAccessOrganisation) {
segment.readSegment();
}
segments.add(segment);
}
if (randomAccessOrganisation) {
for (Iterator it = segments.iterator(); it.hasNext();) {
Segment segment = (Segment) it.next();
segment.readSegment();
}
}
}
public PageInformationSegment findPageSegement(int page) {
for (Iterator it = segments.iterator(); it.hasNext();) {
Segment segment = (Segment) it.next();
SegmentHeader segmentHeader = segment.getSegmentHeader();
if (segmentHeader.getSegmentType() == segment.PAGE_INFORMATION && segmentHeader.getPageAssociation() == page) {
return (PageInformationSegment) segment;
}
}
return null;
}
public Segment findSegment(int segmentNumber) {
for (Iterator it = segments.iterator(); it.hasNext();) {
Segment segment = (Segment) it.next();
if (segment.getSegmentHeader().getSegmentNumber() == segmentNumber) {
return segment;
}
}
return null;
}
private void readSegmentHeader(SegmentHeader segmentHeader) throws IOException, JBIG2Exception {
handleSegmentNumber(segmentHeader);
handleSegmentHeaderFlags(segmentHeader);
handleSegmentReferredToCountAndRententionFlags(segmentHeader);
handleReferedToSegmentNumbers(segmentHeader);
handlePageAssociation(segmentHeader);
if (segmentHeader.getSegmentType() != Segment.END_OF_FILE)
handleSegmentDataLength(segmentHeader);
}
private void handlePageAssociation(SegmentHeader segmentHeader) throws IOException {
int pageAssociation;
boolean isPageAssociationSizeSet = segmentHeader.isPageAssociationSizeSet();
if (isPageAssociationSizeSet) { // field is 4 bytes long
short[] buf = new short[4];
reader.readByte(buf);
pageAssociation = BinaryOperation.getInt32(buf);
} else { // field is 1 byte long
pageAssociation = reader.readByte();
}
segmentHeader.setPageAssociation(pageAssociation);
if (JBIG2StreamDecoder.debug)
System.out.println("pageAssociation = " + pageAssociation);
}
private void handleSegmentNumber(SegmentHeader segmentHeader) throws IOException {
short[] segmentBytes = new short[4];
reader.readByte(segmentBytes);
int segmentNumber = BinaryOperation.getInt32(segmentBytes);
if (JBIG2StreamDecoder.debug)
System.out.println("SegmentNumber = " + segmentNumber);
segmentHeader.setSegmentNumber(segmentNumber);
}
private void handleSegmentHeaderFlags(SegmentHeader segmentHeader) throws IOException {
short segmentHeaderFlags = reader.readByte();
// System.out.println("SegmentHeaderFlags = " + SegmentHeaderFlags);
segmentHeader.setSegmentHeaderFlags(segmentHeaderFlags);
}
private void handleSegmentReferredToCountAndRententionFlags(SegmentHeader segmentHeader) throws IOException, JBIG2Exception {
short referedToSegmentCountAndRetentionFlags = reader.readByte();
int referredToSegmentCount = (referedToSegmentCountAndRetentionFlags & 224) >> 5; // 224
// =
// 11100000
short[] retentionFlags = null;
/** take off the first three bits of the first byte */
short firstByte = (short) (referedToSegmentCountAndRetentionFlags & 31); // 31 =
// 00011111
if (referredToSegmentCount <= 4) { // short form
retentionFlags = new short[1];
retentionFlags[0] = firstByte;
} else if (referredToSegmentCount == 7) { // long form
short[] longFormCountAndFlags = new short[4];
/** add the first byte of the four */
longFormCountAndFlags[0] = firstByte;
for (int i = 1; i < 4; i++)
// add the next 3 bytes to the array
longFormCountAndFlags[i] = reader.readByte();
/** get the count of the referred to Segments */
referredToSegmentCount = BinaryOperation.getInt32(longFormCountAndFlags);
/** calculate the number of bytes in this field */
int noOfBytesInField = (int) Math.ceil(4 + ((referredToSegmentCount + 1) / 8d));
// System.out.println("noOfBytesInField = " + noOfBytesInField);
int noOfRententionFlagBytes = noOfBytesInField - 4;
retentionFlags = new short[noOfRententionFlagBytes];
reader.readByte(retentionFlags);
} else { // error
throw new JBIG2Exception("Error, 3 bit Segment count field = " + referredToSegmentCount);
}
segmentHeader.setReferredToSegmentCount(referredToSegmentCount);
if (JBIG2StreamDecoder.debug)
System.out.println("referredToSegmentCount = " + referredToSegmentCount);
segmentHeader.setRententionFlags(retentionFlags);
if (JBIG2StreamDecoder.debug)
System.out.print("retentionFlags = ");
if (JBIG2StreamDecoder.debug) {
for (int i = 0; i < retentionFlags.length; i++)
System.out.print(retentionFlags[i] + " ");
System.out.println("");
}
}
private void handleReferedToSegmentNumbers(SegmentHeader segmentHeader) throws IOException {
int referredToSegmentCount = segmentHeader.getReferredToSegmentCount();
int[] referredToSegments = new int[referredToSegmentCount];
int segmentNumber = segmentHeader.getSegmentNumber();
if (segmentNumber <= 256) {
for (int i = 0; i < referredToSegmentCount; i++)
referredToSegments[i] = reader.readByte();
} else if (segmentNumber <= 65536) {
short[] buf = new short[2];
for (int i = 0; i < referredToSegmentCount; i++) {
reader.readByte(buf);
referredToSegments[i] = BinaryOperation.getInt16(buf);
}
} else {
short[] buf = new short[4];
for (int i = 0; i < referredToSegmentCount; i++) {
reader.readByte(buf);
referredToSegments[i] = BinaryOperation.getInt32(buf);
}
}
segmentHeader.setReferredToSegments(referredToSegments);
if (JBIG2StreamDecoder.debug) {
System.out.print("referredToSegments = ");
for (int i = 0; i < referredToSegments.length; i++)
System.out.print(referredToSegments[i] + " ");
System.out.println("");
}
}
private int getNoOfPages() throws IOException {
short[] noOfPages = new short[4];
reader.readByte(noOfPages);
return BinaryOperation.getInt32(noOfPages);
}
private void handleSegmentDataLength(SegmentHeader segmentHeader) throws IOException {
short[] buf = new short[4];
reader.readByte(buf);
int dateLength = BinaryOperation.getInt32(buf);
segmentHeader.setDataLength(dateLength);
if (JBIG2StreamDecoder.debug)
System.out.println("dateLength = " + dateLength);
}
private void setFileHeaderFlags() throws IOException {
short headerFlags = reader.readByte();
if ((headerFlags & 0xfc) != 0) {
System.out.println("Warning, reserved bits (2-7) of file header flags are not zero " + headerFlags);
}
int fileOrganisation = headerFlags & 1;
randomAccessOrganisation = fileOrganisation == 0;
int pagesKnown = headerFlags & 2;
noOfPagesKnown = pagesKnown == 0;
}
private boolean checkHeader() throws IOException {
short[] controlHeader = new short[] { 151, 74, 66, 50, 13, 10, 26, 10 };
short[] actualHeader = new short[8];
reader.readByte(actualHeader);
return Arrays.equals(controlHeader, actualHeader);
}
public int readBits(int num) throws IOException {
return reader.readBits(num);
}
public int readBit() throws IOException {
return reader.readBit();
}
public void readByte(short[] buff) throws IOException {
reader.readByte(buff);
}
public void consumeRemainingBits() throws IOException {
reader.consumeRemainingBits();
}
public short readByte() throws java.io.IOException {
return reader.readByte();
}
public void appendBitmap(JBIG2Bitmap bitmap) {
bitmaps.add(bitmap);
}
public JBIG2Bitmap findBitmap(int bitmapNumber) {
for (Iterator it = bitmaps.iterator(); it.hasNext();) {
JBIG2Bitmap bitmap = (JBIG2Bitmap) it.next();
if (bitmap.getBitmapNumber() == bitmapNumber) {
return bitmap;
}
}
return null;
}
public JBIG2Bitmap getPageAsJBIG2Bitmap(int i) {
JBIG2Bitmap pageBitmap = findPageSegement(1).getPageBitmap();
return pageBitmap;
}
public boolean isNumberOfPagesKnown() {
return noOfPagesKnown;
}
public int getNumberOfPages() {
return noOfPages;
}
public boolean isRandomAccessOrganisationUsed() {
return randomAccessOrganisation;
}
public List getAllSegments() {
return segments;
}
}