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 ReadTextRegionFlags()
{
/** extract text region Segment flags */
short[] textRegionFlagsField = new short[2];
decoder.Readbyte(textRegionFlagsField);
int flags = BinaryOperation.GetInt16(textRegionFlagsField);
textRegionFlags.SetFlags(flags);
if (JBIG2StreamDecoder.debug)
{
Console.WriteLine("text region Segment flags = " + flags);
}
bool sbHuff = textRegionFlags.GetFlagValue(TextRegionFlags.SB_HUFF) != 0;
if (sbHuff)
{
/** extract text region Segment Huffman flags */
short[] textRegionHuffmanFlagsField = new short[2];
decoder.Readbyte(textRegionHuffmanFlagsField);
flags = BinaryOperation.GetInt16(textRegionHuffmanFlagsField);
textRegionHuffmanFlags.SetFlags(flags);
if (JBIG2StreamDecoder.debug)
{
Console.WriteLine("text region segment Huffman flags = " + flags);
}
}
bool sbRefine = textRegionFlags.GetFlagValue(TextRegionFlags.SB_REFINE) != 0;
int sbrTemplate = textRegionFlags.GetFlagValue(TextRegionFlags.SB_R_TEMPLATE);
if (sbRefine && sbrTemplate == 0)
{
symbolRegionAdaptiveTemplateX[0] = ReadATValue();
symbolRegionAdaptiveTemplateY[0] = ReadATValue();
symbolRegionAdaptiveTemplateX[1] = ReadATValue();
symbolRegionAdaptiveTemplateY[1] = ReadATValue();
}
}
private void ReadSymbolDictionaryFlags()
{
/** extract symbol dictionary flags */
short[] symbolDictionaryFlagsField = new short[2];
decoder.Readbyte(symbolDictionaryFlagsField);
int flags = BinaryOperation.GetInt16(symbolDictionaryFlagsField);
symbolDictionaryFlags.SetFlags(flags);
if (JBIG2StreamDecoder.debug)
{
Console.WriteLine("symbolDictionaryFlags = " + flags);
}
// symbol dictionary AT flags
int sdHuff = symbolDictionaryFlags.GetFlagValue(SymbolDictionaryFlags.SD_HUFF);
int sdTemplate = symbolDictionaryFlags.GetFlagValue(SymbolDictionaryFlags.SD_TEMPLATE);
if (sdHuff == 0)
{
if (sdTemplate == 0)
{
symbolDictionaryAdaptiveTemplateX[0] = ReadATValue();
symbolDictionaryAdaptiveTemplateY[0] = ReadATValue();
symbolDictionaryAdaptiveTemplateX[1] = ReadATValue();
symbolDictionaryAdaptiveTemplateY[1] = ReadATValue();
symbolDictionaryAdaptiveTemplateX[2] = ReadATValue();
symbolDictionaryAdaptiveTemplateY[2] = ReadATValue();
symbolDictionaryAdaptiveTemplateX[3] = ReadATValue();
symbolDictionaryAdaptiveTemplateY[3] = ReadATValue();
}
else
{
symbolDictionaryAdaptiveTemplateX[0] = ReadATValue();
symbolDictionaryAdaptiveTemplateY[0] = ReadATValue();
}
}
// symbol dictionary refinement AT flags
int refAgg = symbolDictionaryFlags.GetFlagValue(SymbolDictionaryFlags.SD_REF_AGG);
int sdrTemplate = symbolDictionaryFlags.GetFlagValue(SymbolDictionaryFlags.SD_R_TEMPLATE);
if (refAgg != 0 && sdrTemplate == 0)
{
symbolDictionaryRAdaptiveTemplateX[0] = ReadATValue();
symbolDictionaryRAdaptiveTemplateY[0] = ReadATValue();
symbolDictionaryRAdaptiveTemplateX[1] = ReadATValue();
symbolDictionaryRAdaptiveTemplateY[1] = ReadATValue();
}
/** extract no of exported symbols */
short[] noOfExportedSymbolsField = new short[4];
decoder.Readbyte(noOfExportedSymbolsField);
int noOfExportedSymbols = BinaryOperation.GetInt32(noOfExportedSymbolsField);
this.noOfExportedSymbols = noOfExportedSymbols;
if (JBIG2StreamDecoder.debug)
{
Console.WriteLine("noOfExportedSymbols = " + noOfExportedSymbols);
}
/** extract no of new symbols */
short[] noOfNewSymbolsField = new short[4];
decoder.Readbyte(noOfNewSymbolsField);
int noOfNewSymbols = BinaryOperation.GetInt32(noOfNewSymbolsField);
this.noOfNewSymbols = noOfNewSymbols;
if (JBIG2StreamDecoder.debug)
{
Console.WriteLine("noOfNewSymbols = " + noOfNewSymbols);
}
}
public override void ReadSegment()
{
if (JBIG2StreamDecoder.debug)
{
Console.WriteLine("==== Reading Page Information Dictionary ====");
}
short[] buff = new short[4];
decoder.Readbyte(buff);
pageBitmapWidth = BinaryOperation.GetInt32(buff);
buff = new short[4];
decoder.Readbyte(buff);
pageBitmapHeight = BinaryOperation.GetInt32(buff);
if (JBIG2StreamDecoder.debug)
{
Console.WriteLine("Bitmap size = " + pageBitmapWidth + 'x' + pageBitmapHeight);
}
buff = new short[4];
decoder.Readbyte(buff);
xResolution = BinaryOperation.GetInt32(buff);
buff = new short[4];
decoder.Readbyte(buff);
yResolution = BinaryOperation.GetInt32(buff);
if (JBIG2StreamDecoder.debug)
{
Console.WriteLine("Resolution = " + xResolution + 'x' + yResolution);
}
/** extract page information flags */
short pageInformationFlagsField = decoder.Readbyte();
pageInformationFlags.SetFlags(pageInformationFlagsField);
if (JBIG2StreamDecoder.debug)
{
Console.WriteLine("symbolDictionaryFlags = " + pageInformationFlagsField);
}
buff = new short[2];
decoder.Readbyte(buff);
pageStriping = BinaryOperation.GetInt16(buff);
if (JBIG2StreamDecoder.debug)
{
Console.WriteLine("Page Striping = " + pageStriping);
}
int defPix = pageInformationFlags.GetFlagValue(PageInformationFlags.DEFAULT_PIXEL_VALUE);
int height;
if (pageBitmapHeight == -1)
{
height = pageStriping & 0x7fff;
}
else
{
height = pageBitmapHeight;
}
pageBitmap = new JBIG2Bitmap(pageBitmapWidth, height, arithmeticDecoder, huffmanDecoder, mmrDecoder);
pageBitmap.Clear(defPix);
}
public override void ReadSegment()
{
base.ReadSegment();
/** read text region Segment flags */
ReadHalftoneRegionFlags();
short[] buf = new short[4];
decoder.Readbyte(buf);
int gridWidth = BinaryOperation.GetInt32(buf);
buf = new short[4];
decoder.Readbyte(buf);
int gridHeight = BinaryOperation.GetInt32(buf);
buf = new short[4];
decoder.Readbyte(buf);
int gridX = BinaryOperation.GetInt32(buf);
buf = new short[4];
decoder.Readbyte(buf);
int gridY = BinaryOperation.GetInt32(buf);
if (JBIG2StreamDecoder.debug)
{
Console.WriteLine("grid pos and size = " + gridX + ',' + gridY + ' ' + gridWidth + ',' + gridHeight);
}
buf = new short[2];
decoder.Readbyte(buf);
int stepX = BinaryOperation.GetInt16(buf);
buf = new short[2];
decoder.Readbyte(buf);
int stepY = BinaryOperation.GetInt16(buf);
if (JBIG2StreamDecoder.debug)
{
Console.WriteLine("step size = " + stepX + ',' + stepY);
}
int[] referedToSegments = segmentHeader.GetReferredToSegments();
if (referedToSegments.Length != 1)
{
Console.WriteLine("Error in halftone Segment. refSegs should == 1");
}
Segment segment = decoder.FindSegment(referedToSegments[0]);
if (segment.GetSegmentHeader().GetSegmentType() != Segment.PATTERN_DICTIONARY)
{
if (JBIG2StreamDecoder.debug)
{
Console.WriteLine("Error in halftone Segment. bad symbol dictionary reference");
}
}
PatternDictionarySegment patternDictionarySegment = (PatternDictionarySegment)segment;
int bitsPerValue = 0, i = 1;
while (i < patternDictionarySegment.GetSize())
{
bitsPerValue++;
i <<= 1;
}
JBIG2Bitmap bitmap = patternDictionarySegment.GetBitmaps()[0];
long patternWidth = bitmap.GetWidth();
long patternHeight = bitmap.GetHeight();
if (JBIG2StreamDecoder.debug)
{
Console.WriteLine("pattern size = " + patternWidth + ',' + patternHeight);
}
bool useMMR = halftoneRegionFlags.GetFlagValue(HalftoneRegionFlags.H_MMR) != 0;
int template = halftoneRegionFlags.GetFlagValue(HalftoneRegionFlags.H_TEMPLATE);
if (!useMMR)
{
arithmeticDecoder.ResetGenericStats(template, null);
arithmeticDecoder.Start();
}
int halftoneDefaultPixel = halftoneRegionFlags.GetFlagValue(HalftoneRegionFlags.H_DEF_PIXEL);
bitmap = new JBIG2Bitmap(regionBitmapWidth, regionBitmapHeight, arithmeticDecoder, huffmanDecoder, mmrDecoder);
bitmap.Clear(halftoneDefaultPixel);
bool enableSkip = halftoneRegionFlags.GetFlagValue(HalftoneRegionFlags.H_ENABLE_SKIP) != 0;
JBIG2Bitmap skipBitmap = null;
if (enableSkip)
{
skipBitmap = new JBIG2Bitmap(gridWidth, gridHeight, arithmeticDecoder, huffmanDecoder, mmrDecoder);
skipBitmap.Clear(0);
for (int y = 0; y < gridHeight; y++)
{
for (int x = 0; x < gridWidth; x++)
{
int xx = gridX + y * stepY + x * stepX;
int yy = gridY + y * stepX - x * stepY;
if (((xx + patternWidth) >> 8) <= 0 || (xx >> 8) >= regionBitmapWidth || ((yy + patternHeight) >> 8) <= 0 || (yy >> 8) >= regionBitmapHeight)
{
skipBitmap.SetPixel(y, x, 1);
}
}
}
}
int[] grayScaleImage = new int[gridWidth * gridHeight];
short[] genericBAdaptiveTemplateX = new short[4], genericBAdaptiveTemplateY = new short[4];
genericBAdaptiveTemplateX[0] = (short)(template <= 1 ? 3 : 2);
genericBAdaptiveTemplateY[0] = -1;
genericBAdaptiveTemplateX[1] = -3;
genericBAdaptiveTemplateY[1] = -1;
genericBAdaptiveTemplateX[2] = 2;
genericBAdaptiveTemplateY[2] = -2;
genericBAdaptiveTemplateX[3] = -2;
genericBAdaptiveTemplateY[3] = -2;
JBIG2Bitmap grayBitmap;
for (int j = bitsPerValue - 1; j >= 0; --j)
{
grayBitmap = new JBIG2Bitmap(gridWidth, gridHeight, arithmeticDecoder, huffmanDecoder, mmrDecoder);
grayBitmap.ReadBitmap(useMMR, template, false, enableSkip, skipBitmap, genericBAdaptiveTemplateX, genericBAdaptiveTemplateY, -1);
i = 0;
for (int row = 0; row < gridHeight; row++)
{
for (int col = 0; col < gridWidth; col++)
{
int bit = grayBitmap.GetPixel(col, row) ^ grayScaleImage[i] & 1;
grayScaleImage[i] = (grayScaleImage[i] << 1) | bit;
i++;
}
}
}
int combinationOperator = halftoneRegionFlags.GetFlagValue(HalftoneRegionFlags.H_COMB_OP);
i = 0;
for (int col = 0; col < gridHeight; col++)
{
int xx = gridX + col * stepY;
int yy = gridY + col * stepX;
for (int row = 0; row < gridWidth; row++)
{
if (!(enableSkip && skipBitmap.GetPixel(col, row) == 1))
{
JBIG2Bitmap patternBitmap = patternDictionarySegment.GetBitmaps()[grayScaleImage[i]];
bitmap.Combine(patternBitmap, xx >> 8, yy >> 8, combinationOperator);
}
xx += stepX;
yy -= stepY;
i++;
}
}
if (inlineImage)
{
PageInformationSegment pageSegment = decoder.FindPageSegement(segmentHeader.GetPageAssociation());
JBIG2Bitmap pageBitmap = pageSegment.GetPageBitmap();
int externalCombinationOperator = regionFlags.GetFlagValue(RegionFlags.EXTERNAL_COMBINATION_OPERATOR);
pageBitmap.Combine(bitmap, regionBitmapXLocation, regionBitmapYLocation, externalCombinationOperator);
}
else
{
bitmap.SetBitmapNumber(GetSegmentHeader().GetSegmentNumber());
decoder.AppendBitmap(bitmap);
}
}