jbig2stream.cc

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  Guint i;

  for (i = 0; i < size; ++i) {
    delete bitmaps[i];
  }
  gfree(bitmaps);
  if (genericRegionStats) {
    delete genericRegionStats;
  }
  if (refinementRegionStats) {
    delete refinementRegionStats;
  }
}

//------------------------------------------------------------------------
// JBIG2PatternDict
//------------------------------------------------------------------------

class JBIG2PatternDict: public JBIG2Segment {
public:

  JBIG2PatternDict(Guint segNumA, Guint sizeA);
  virtual ~JBIG2PatternDict();
  virtual JBIG2SegmentType getType() { return jbig2SegPatternDict; }
  Guint getSize() { return size; }
  void setBitmap(Guint idx, JBIG2Bitmap *bitmap) { bitmaps[idx] = bitmap; }
  JBIG2Bitmap *getBitmap(Guint idx) { return bitmaps[idx]; }

private:

  Guint size;
  JBIG2Bitmap **bitmaps;
};

JBIG2PatternDict::JBIG2PatternDict(Guint segNumA, Guint sizeA):
  JBIG2Segment(segNumA)
{
  size = sizeA;
  bitmaps = (JBIG2Bitmap **)gmallocn(size, sizeof(JBIG2Bitmap *));
}

JBIG2PatternDict::~JBIG2PatternDict() {
  Guint i;

  for (i = 0; i < size; ++i) {
    delete bitmaps[i];
  }
  gfree(bitmaps);
}

//------------------------------------------------------------------------
// JBIG2CodeTable
//------------------------------------------------------------------------

class JBIG2CodeTable: public JBIG2Segment {
public:

  JBIG2CodeTable(Guint segNumA, JBIG2HuffmanTable *tableA);
  virtual ~JBIG2CodeTable();
  virtual JBIG2SegmentType getType() { return jbig2SegCodeTable; }
  JBIG2HuffmanTable *getHuffTable() { return table; }

private:

  JBIG2HuffmanTable *table;
};

JBIG2CodeTable::JBIG2CodeTable(Guint segNumA, JBIG2HuffmanTable *tableA):
  JBIG2Segment(segNumA)
{
  table = tableA;
}

JBIG2CodeTable::~JBIG2CodeTable() {
  gfree(table);
}

//------------------------------------------------------------------------
// JBIG2Stream
//------------------------------------------------------------------------

JBIG2Stream::JBIG2Stream(Stream *strA, Object *globalsStreamA):
  FilterStream(strA)
{
  pageBitmap = NULL;

  arithDecoder = new JArithmeticDecoder();
  genericRegionStats = new JArithmeticDecoderStats(1 << 1);
  refinementRegionStats = new JArithmeticDecoderStats(1 << 1);
  iadhStats = new JArithmeticDecoderStats(1 << 9);
  iadwStats = new JArithmeticDecoderStats(1 << 9);
  iaexStats = new JArithmeticDecoderStats(1 << 9);
  iaaiStats = new JArithmeticDecoderStats(1 << 9);
  iadtStats = new JArithmeticDecoderStats(1 << 9);
  iaitStats = new JArithmeticDecoderStats(1 << 9);
  iafsStats = new JArithmeticDecoderStats(1 << 9);
  iadsStats = new JArithmeticDecoderStats(1 << 9);
  iardxStats = new JArithmeticDecoderStats(1 << 9);
  iardyStats = new JArithmeticDecoderStats(1 << 9);
  iardwStats = new JArithmeticDecoderStats(1 << 9);
  iardhStats = new JArithmeticDecoderStats(1 << 9);
  iariStats = new JArithmeticDecoderStats(1 << 9);
  iaidStats = new JArithmeticDecoderStats(1 << 1);
  huffDecoder = new JBIG2HuffmanDecoder();
  mmrDecoder = new JBIG2MMRDecoder();

  globalsStreamA->copy(&globalsStream);
  segments = globalSegments = NULL;
  curStr = NULL;
  dataPtr = dataEnd = NULL;
}

JBIG2Stream::~JBIG2Stream() {
  close();
  globalsStream.free();
  delete arithDecoder;
  delete genericRegionStats;
  delete refinementRegionStats;
  delete iadhStats;
  delete iadwStats;
  delete iaexStats;
  delete iaaiStats;
  delete iadtStats;
  delete iaitStats;
  delete iafsStats;
  delete iadsStats;
  delete iardxStats;
  delete iardyStats;
  delete iardwStats;
  delete iardhStats;
  delete iariStats;
  delete iaidStats;
  delete huffDecoder;
  delete mmrDecoder;
  delete str;
}

void JBIG2Stream::reset() {
  // read the globals stream
  globalSegments = new GList();
  if (globalsStream.isStream()) {
    segments = globalSegments;
    curStr = globalsStream.getStream();
    curStr->reset();
    arithDecoder->setStream(curStr);
    huffDecoder->setStream(curStr);
    mmrDecoder->setStream(curStr);
    readSegments();
    curStr->close();
  }

  // read the main stream
  segments = new GList();
  curStr = str;
  curStr->reset();
  arithDecoder->setStream(curStr);
  huffDecoder->setStream(curStr);
  mmrDecoder->setStream(curStr);
  readSegments();

  if (pageBitmap) {
    dataPtr = pageBitmap->getDataPtr();
    dataEnd = dataPtr + pageBitmap->getDataSize();
  } else {
    dataPtr = dataEnd = NULL;
  }
}

void JBIG2Stream::close() {
  if (pageBitmap) {
    delete pageBitmap;
    pageBitmap = NULL;
  }
  if (segments) {
    deleteGList(segments, JBIG2Segment);
    segments = NULL;
  }
  if (globalSegments) {
    deleteGList(globalSegments, JBIG2Segment);
    globalSegments = NULL;
  }
  dataPtr = dataEnd = NULL;
  FilterStream::close();
}

int JBIG2Stream::getChar() {
  if (dataPtr && dataPtr < dataEnd) {
    return (*dataPtr++ ^ 0xff) & 0xff;
  }
  return EOF;
}

int JBIG2Stream::lookChar() {
  if (dataPtr && dataPtr < dataEnd) {
    return (*dataPtr ^ 0xff) & 0xff;
  }
  return EOF;
}

GString *JBIG2Stream::getPSFilter(int psLevel, char *indent) {
  return NULL;
}

GBool JBIG2Stream::isBinary(GBool last) {
  return str->isBinary(gTrue);
}

void JBIG2Stream::readSegments() {
  Guint segNum, segFlags, segType, page, segLength;
  Guint refFlags, nRefSegs;
  Guint *refSegs;
  int c1, c2, c3;
  Guint i;

  while (readULong(&segNum)) {

    // segment header flags
    if (!readUByte(&segFlags)) {
      goto eofError1;
    }
    segType = segFlags & 0x3f;

    // referred-to segment count and retention flags
    if (!readUByte(&refFlags)) {
      goto eofError1;
    }
    nRefSegs = refFlags >> 5;
    if (nRefSegs == 7) {
      if ((c1 = curStr->getChar()) == EOF ||
	  (c2 = curStr->getChar()) == EOF ||
	  (c3 = curStr->getChar()) == EOF) {
	goto eofError1;
      }
      refFlags = (refFlags << 24) | (c1 << 16) | (c2 << 8) | c3;
      nRefSegs = refFlags & 0x1fffffff;
      for (i = 0; i < (nRefSegs + 9) >> 3; ++i) {
	c1 = curStr->getChar();
      }
    }

    // referred-to segment numbers
    refSegs = (Guint *)gmallocn(nRefSegs, sizeof(Guint));
    if (segNum <= 256) {
      for (i = 0; i < nRefSegs; ++i) {
	if (!readUByte(&refSegs[i])) {
	  goto eofError2;
	}
      }
    } else if (segNum <= 65536) {
      for (i = 0; i < nRefSegs; ++i) {
	if (!readUWord(&refSegs[i])) {
	  goto eofError2;
	}
      }
    } else {
      for (i = 0; i < nRefSegs; ++i) {
	if (!readULong(&refSegs[i])) {
	  goto eofError2;
	}
      }
    }

    // segment page association
    if (segFlags & 0x40) {
      if (!readULong(&page)) {
	goto eofError2;
      }
    } else {
      if (!readUByte(&page)) {
	goto eofError2;
      }
    }

    // segment data length
    if (!readULong(&segLength)) {
      goto eofError2;
    }

    // read the segment data
    switch (segType) {
    case 0:
      if (!readSymbolDictSeg(segNum, segLength, refSegs, nRefSegs)) {
	goto syntaxError;
      }
      break;
    case 4:
      readTextRegionSeg(segNum, gFalse, gFalse, segLength, refSegs, nRefSegs);
      break;
    case 6:
      readTextRegionSeg(segNum, gTrue, gFalse, segLength, refSegs, nRefSegs);
      break;
    case 7:
      readTextRegionSeg(segNum, gTrue, gTrue, segLength, refSegs, nRefSegs);
      break;
    case 16:
      readPatternDictSeg(segNum, segLength);
      break;
    case 20:
      readHalftoneRegionSeg(segNum, gFalse, gFalse, segLength,
			    refSegs, nRefSegs);
      break;
    case 22:
      readHalftoneRegionSeg(segNum, gTrue, gFalse, segLength,
			    refSegs, nRefSegs);
      break;
    case 23:
      readHalftoneRegionSeg(segNum, gTrue, gTrue, segLength,
			    refSegs, nRefSegs);
      break;
    case 36:
      readGenericRegionSeg(segNum, gFalse, gFalse, segLength);
      break;
    case 38:
      readGenericRegionSeg(segNum, gTrue, gFalse, segLength);
      break;
    case 39:
      readGenericRegionSeg(segNum, gTrue, gTrue, segLength);
      break;
    case 40:
      readGenericRefinementRegionSeg(segNum, gFalse, gFalse, segLength,
				     refSegs, nRefSegs);
      break;
    case 42:
      readGenericRefinementRegionSeg(segNum, gTrue, gFalse, segLength,
				     refSegs, nRefSegs);
      break;
    case 43:
      readGenericRefinementRegionSeg(segNum, gTrue, gTrue, segLength,
				     refSegs, nRefSegs);
      break;
    case 48:
      readPageInfoSeg(segLength);
      break;
    case 50:
      readEndOfStripeSeg(segLength);
      break;
    case 52:
      readProfilesSeg(segLength);
      break;
    case 53:
      readCodeTableSeg(segNum, segLength);
      break;
    case 62:
      readExtensionSeg(segLength);
      break;
    default:
      error(getPos(), "Unknown segment type in JBIG2 stream");
      for (i = 0; i < segLength; ++i) {
	if ((c1 = curStr->getChar()) == EOF) {
	  goto eofError2;
	}
      }
      break;
    }

    gfree(refSegs);
  }

  return;

 syntaxError:
  gfree(refSegs);
  return;

 eofError2:
  gfree(refSegs);
 eofError1:
  error(getPos(), "Unexpected EOF in JBIG2 stream");
}

GBool JBIG2Stream::readSymbolDictSeg(Guint segNum, Guint length,
				     Guint *refSegs, Guint nRefSegs) {
  JBIG2SymbolDict *symbolDict;
  JBIG2HuffmanTable *huffDHTable, *huffDWTable;
  JBIG2HuffmanTable *huffBMSizeTable, *huffAggInstTable;
  JBIG2Segment *seg;
  GList *codeTables;
  JBIG2SymbolDict *inputSymbolDict;
  Guint flags, sdTemplate, sdrTemplate, huff, refAgg;
  Guint huffDH, huffDW, huffBMSize, huffAggInst;
  Guint contextUsed, contextRetained;
  int sdATX[4], sdATY[4], sdrATX[2], sdrATY[2];
  Guint numExSyms, numNewSyms, numInputSyms, symCodeLen;
  JBIG2Bitmap **bitmaps;
  JBIG2Bitmap *collBitmap, *refBitmap;
  Guint *symWidths;
  Guint symHeight, symWidth, totalWidth, x, symID;
  int dh, dw, refAggNum, refDX, refDY, bmSize;
  GBool ex;
  int run, cnt;
  Guint i, j, k;
  Guchar *p;

  // symbol dictionary flags
  if (!readUWord(&flags)) {
    goto eofError;
  }
  sdTemplate = (flags >> 10) & 3;
  sdrTemplate = (flags >> 12) & 1;
  huff = flags & 1;
  refAgg = (flags >> 1) & 1;
  huffDH = (flags >> 2) & 3;
  huffDW = (flags >> 4) & 3;
  huffBMSize = (flags >> 6) & 1;
  huffAggInst = (flags >> 7) & 1;
  contextUsed = (flags >> 8) & 1;
  contextRetained = (flags >> 9) & 1;

  // symbol dictionary AT flags
  if (!huff) {
    if (sdTemplate == 0) {
      if (!readByte(&sdATX[0]) ||
	  !readByte(&sdATY[0]) ||
	  !readByte(&sdATX[1]) ||
	  !readByte(&sdATY[1]) ||
	  !readByte(&sdATX[2]) ||
	  !readByte(&sdATY[2]) ||
	  !readByte(&sdATX[3]) ||
	  !readByte(&sdATY[3])) {
	goto eofError;
      }
    } else {
      if (!readByte(&sdATX[0]) ||
	  !readByte(&sdATY[0])) {
	goto eofError;
      }
    }
  }

  // symbol dictionary refinement AT flags
  if (refAgg && !sdrTemplate) {
    if (!readByte(&sdrATX[0]) ||
	!readByte(&sdrATY[0]) ||
	!readByte(&sdrATX[1]) ||
	!readByte(&sdrATY[1])) {
      goto eofError;
    }
  }

  // SDNUMEXSYMS and SDNUMNEWSYMS
  if (!readULong(&numExSyms) || !readULong(&numNewSyms)) {
    goto eofError;
  }

  // get referenced segments: input symbol dictionaries and code tables
  codeTables = new GList();
  numInputSyms = 0;
  for (i = 0; i < nRefSegs; ++i) {
    seg = findSegment(refSegs[i]);
    if (seg->getType() == jbig2SegSymbolDict) {
      numInputSyms += ((JBIG2SymbolDict *)seg)->getSize();
    } else if (seg->getType() == jbig2SegCodeTable) {
      codeTables->append(seg);
    }
  }

  // compute symbol code length
  symCodeLen = 0;
  i = 1;
  while (i < numInputSyms + numNewSyms) {
    ++symCodeLen;
    i <<= 1;
  }

  // get the input symbol bitmaps
  bitmaps = (JBIG2Bitmap **)gmallocn(numInputSyms + numNewSyms,
				     sizeof(JBIG2Bitmap *));
  for (i = 0; i < numInputSyms + numNewSyms; ++i) {
    bitmaps[i] = NULL;
  }
  k = 0;
  inputSymbolDict = NULL;
  for (i = 0; i < nRefSegs; ++i) {
    seg = findSegment(refSegs[i]);
    if (seg->getType() == jbig2SegSymbolDict) {
      inputSymbolDict = (JBIG2SymbolDict *)seg;
      for (j = 0; j < inputSymbolDict->getSize(); ++j) {
	bitmaps[k++] = inputSymbolDict->getBitmap(j);
      }
    }
  }

  // get the Huffman tables
  huffDHTable = huffDWTable = NULL; // make gcc happy
  huffBMSizeTable = huffAggInstTable = NULL; // make gcc happy
  i = 0;
  if (huff) {
    if (huffDH == 0) {
      huffDHTable = huffTableD;
    } else if (huffDH == 1) {
      huffDHTable = huffTableE;
    } else {
      huffDHTable = ((JBIG2CodeTable *)codeTables->get(i++))->getHuffTable();
    }
    if (huffDW == 0) {
      huffDWTable = huffTableB;
    } else if (huffDW == 1) {
      huffDWTable = huffTableC;
    } else {
      huffDWTable = ((JBIG2CodeTable *)codeTables->get(i++))->getHuffTable();
    }
    if (huffBMSize == 0) {
      huffBMSizeTable = huffTableA;
    } else {
      huffBMSizeTable =
	  ((JBIG2CodeTable *)codeTables->get(i++))->getHuffTable();
    }
    if (huffAggInst == 0) {
      huffAggInstTable = huffTableA;
    } else {