private void handleSegmentHeaderFlags(SegmentHeader segmentHeader)
{
short segmentHeaderFlags = reader.readbyte();
// System.out.println("SegmentHeaderFlags = " + SegmentHeaderFlags);
segmentHeader.setSegmentHeaderFlags(segmentHeaderFlags);
}
private void handleSegmentNumber(SegmentHeader segmentHeader)
{
short[] segmentbytes = new short[4];
reader.readbyte(segmentbytes);
int segmentNumber = BinaryOperation.getInt32(segmentbytes);
if (JBIG2StreamDecoder.debug)
{
Console.WriteLine("SegmentNumber = " + segmentNumber);
}
segmentHeader.setSegmentNumber(segmentNumber);
}
public PageInformationSegment findPageSegement(int page)
{
foreach (Segment segment in segments)
{
SegmentHeader segmentHeader = segment.getSegmentHeader();
if (segmentHeader.getSegmentType() == Segment.PAGE_INFORMATION && segmentHeader.getPageAssociation() == page)
{
return((PageInformationSegment)segment);
}
}
return(null);
}
private void handleSegmentDataLength(SegmentHeader segmentHeader)
{
short[] buf = new short[4];
reader.readbyte(buf);
int dateLength = BinaryOperation.getInt32(buf);
segmentHeader.setDataLength(dateLength);
if (JBIG2StreamDecoder.debug)
{
Console.WriteLine("dateLength = " + dateLength);
}
}
private void handleReferedToSegmentNumbers(SegmentHeader segmentHeader)
{
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)
{
Console.WriteLine("referredToSegments = ");
for (int i = 0; i < referredToSegments.Length; i++)
{
Console.WriteLine(referredToSegments[i] + " ");
}
Console.WriteLine("");
}
}
private void readSegmentHeader(SegmentHeader segmentHeader)
{
handleSegmentNumber(segmentHeader);
handleSegmentHeaderFlags(segmentHeader);
handleSegmentReferredToCountAndRententionFlags(segmentHeader);
handleReferedToSegmentNumbers(segmentHeader);
handlePageAssociation(segmentHeader);
if (segmentHeader.getSegmentType() != Segment.END_OF_FILE)
{
handleSegmentDataLength(segmentHeader);
}
}
private void handlePageAssociation(SegmentHeader segmentHeader)
{
int pageAssociation;
bool 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)
{
Console.WriteLine("pageAssociation = " + pageAssociation);
}
}
private void handleSegmentReferredToCountAndRententionFlags(SegmentHeader segmentHeader)
{
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.Ceiling(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)
{
Console.WriteLine("referredToSegmentCount = " + referredToSegmentCount);
}
segmentHeader.setRententionFlags(retentionFlags);
if (JBIG2StreamDecoder.debug)
{
Console.WriteLine("retentionFlags = ");
}
if (JBIG2StreamDecoder.debug)
{
for (int i = 0; i < retentionFlags.Length; i++)
{
Console.WriteLine(retentionFlags[i] + " ");
}
Console.WriteLine("");
}
}
private void readSegments()
{
bool finished = false;
while (!reader.isFinished() && !finished)
{
SegmentHeader segmentHeader = new SegmentHeader();
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:
segment = new SymbolDictionarySegment(this);
segment.setSegmentHeader(segmentHeader);
break;
case Segment.INTERMEDIATE_TEXT_REGION:
segment = new TextRegionSegment(this, false);
segment.setSegmentHeader(segmentHeader);
break;
case Segment.IMMEDIATE_TEXT_REGION:
segment = new TextRegionSegment(this, true);
segment.setSegmentHeader(segmentHeader);
break;
case Segment.IMMEDIATE_LOSSLESS_TEXT_REGION:
segment = new TextRegionSegment(this, true);
segment.setSegmentHeader(segmentHeader);
break;
case Segment.PATTERN_DICTIONARY:
segment = new PatternDictionarySegment(this);
segment.setSegmentHeader(segmentHeader);
break;
case Segment.INTERMEDIATE_HALFTONE_REGION:
segment = new HalftoneRegionSegment(this, false);
segment.setSegmentHeader(segmentHeader);
break;
case Segment.IMMEDIATE_HALFTONE_REGION:
segment = new HalftoneRegionSegment(this, true);
segment.setSegmentHeader(segmentHeader);
break;
case Segment.IMMEDIATE_LOSSLESS_HALFTONE_REGION:
segment = new HalftoneRegionSegment(this, true);
segment.setSegmentHeader(segmentHeader);
break;
case Segment.INTERMEDIATE_GENERIC_REGION:
segment = new GenericRegionSegment(this, false);
segment.setSegmentHeader(segmentHeader);
break;
case Segment.IMMEDIATE_GENERIC_REGION:
segment = new GenericRegionSegment(this, true);
segment.setSegmentHeader(segmentHeader);
break;
case Segment.IMMEDIATE_LOSSLESS_GENERIC_REGION:
segment = new GenericRegionSegment(this, true);
segment.setSegmentHeader(segmentHeader);
break;
case Segment.INTERMEDIATE_GENERIC_REFINEMENT_REGION:
segment = new RefinementRegionSegment(this, false, referredToSegments, noOfReferredToSegments);
segment.setSegmentHeader(segmentHeader);
break;
case Segment.IMMEDIATE_GENERIC_REFINEMENT_REGION:
segment = new RefinementRegionSegment(this, true, referredToSegments, noOfReferredToSegments);
segment.setSegmentHeader(segmentHeader);
break;
case Segment.IMMEDIATE_LOSSLESS_GENERIC_REFINEMENT_REGION:
segment = new RefinementRegionSegment(this, true, referredToSegments, noOfReferredToSegments);
segment.setSegmentHeader(segmentHeader);
break;
case Segment.PAGE_INFORMATION:
segment = new PageInformationSegment(this);
segment.setSegmentHeader(segmentHeader);
break;
case Segment.END_OF_PAGE:
continue;
case Segment.END_OF_STRIPE:
segment = new EndOfStripeSegment(this);
segment.setSegmentHeader(segmentHeader);
break;
case Segment.END_OF_FILE:
finished = true;
continue;
case Segment.PROFILES:
break;
case Segment.TABLES:
break;
case Segment.EXTENSION:
segment = new ExtensionSegment(this);
segment.setSegmentHeader(segmentHeader);
break;
default:
break;
}
if (!randomAccessOrganisation)
{
segment.readSegment();
}
segments.Add(segment);
}
if (randomAccessOrganisation)
{
foreach (Segment segment in segments)
{
segment.readSegment();
}
}
}
public void setSegmentHeader(SegmentHeader segmentHeader)
{
this.segmentHeader = segmentHeader;
}