jbig2stream.cc

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//========================================================================
//
// JBIG2Stream.cc
//
// Copyright 2002-2003 Glyph & Cog, LLC
//
//========================================================================

#include <aconf.h>

#ifdef USE_GCC_PRAGMAS
#pragma implementation
#endif

#include <stdlib.h>
#include <limits.h>
#include "GList.h"
#include "Error.h"
#include "JArithmeticDecoder.h"
#include "JBIG2Stream.h"

//~ share these tables
#include "Stream-CCITT.h"

//------------------------------------------------------------------------

static int contextSize[4] = { 16, 13, 10, 10 };
static int refContextSize[2] = { 13, 10 };

//------------------------------------------------------------------------
// JBIG2HuffmanTable
//------------------------------------------------------------------------

#define jbig2HuffmanLOW 0xfffffffd
#define jbig2HuffmanOOB 0xfffffffe
#define jbig2HuffmanEOT 0xffffffff

struct JBIG2HuffmanTable {
  int val;
  Guint prefixLen;
  Guint rangeLen;		// can also be LOW, OOB, or EOT
  Guint prefix;
};

JBIG2HuffmanTable huffTableA[] = {
  {     0, 1,  4,              0x000 },
  {    16, 2,  8,              0x002 },
  {   272, 3, 16,              0x006 },
  { 65808, 3, 32,              0x007 },
  {     0, 0, jbig2HuffmanEOT, 0     }
};

JBIG2HuffmanTable huffTableB[] = {
  {     0, 1,  0,              0x000 },
  {     1, 2,  0,              0x002 },
  {     2, 3,  0,              0x006 },
  {     3, 4,  3,              0x00e },
  {    11, 5,  6,              0x01e },
  {    75, 6, 32,              0x03e },
  {     0, 6, jbig2HuffmanOOB, 0x03f },
  {     0, 0, jbig2HuffmanEOT, 0     }
};

JBIG2HuffmanTable huffTableC[] = {
  {     0, 1,  0,              0x000 },
  {     1, 2,  0,              0x002 },
  {     2, 3,  0,              0x006 },
  {     3, 4,  3,              0x00e },
  {    11, 5,  6,              0x01e },
  {     0, 6, jbig2HuffmanOOB, 0x03e },
  {    75, 7, 32,              0x0fe },
  {  -256, 8,  8,              0x0fe },
  {  -257, 8, jbig2HuffmanLOW, 0x0ff },
  {     0, 0, jbig2HuffmanEOT, 0     }
};

JBIG2HuffmanTable huffTableD[] = {
  {     1, 1,  0,              0x000 },
  {     2, 2,  0,              0x002 },
  {     3, 3,  0,              0x006 },
  {     4, 4,  3,              0x00e },
  {    12, 5,  6,              0x01e },
  {    76, 5, 32,              0x01f },
  {     0, 0, jbig2HuffmanEOT, 0     }
};

JBIG2HuffmanTable huffTableE[] = {
  {     1, 1,  0,              0x000 },
  {     2, 2,  0,              0x002 },
  {     3, 3,  0,              0x006 },
  {     4, 4,  3,              0x00e },
  {    12, 5,  6,              0x01e },
  {    76, 6, 32,              0x03e },
  {  -255, 7,  8,              0x07e },
  {  -256, 7, jbig2HuffmanLOW, 0x07f },
  {     0, 0, jbig2HuffmanEOT, 0     }
};

JBIG2HuffmanTable huffTableF[] = {
  {     0, 2,  7,              0x000 },
  {   128, 3,  7,              0x002 },
  {   256, 3,  8,              0x003 },
  { -1024, 4,  9,              0x008 },
  {  -512, 4,  8,              0x009 },
  {  -256, 4,  7,              0x00a },
  {   -32, 4,  5,              0x00b },
  {   512, 4,  9,              0x00c },
  {  1024, 4, 10,              0x00d },
  { -2048, 5, 10,              0x01c },
  {  -128, 5,  6,              0x01d },
  {   -64, 5,  5,              0x01e },
  { -2049, 6, jbig2HuffmanLOW, 0x03e },
  {  2048, 6, 32,              0x03f },
  {     0, 0, jbig2HuffmanEOT, 0     }
};

JBIG2HuffmanTable huffTableG[] = {
  {  -512, 3,  8,              0x000 },
  {   256, 3,  8,              0x001 },
  {   512, 3,  9,              0x002 },
  {  1024, 3, 10,              0x003 },
  { -1024, 4,  9,              0x008 },
  {  -256, 4,  7,              0x009 },
  {   -32, 4,  5,              0x00a },
  {     0, 4,  5,              0x00b },
  {   128, 4,  7,              0x00c },
  {  -128, 5,  6,              0x01a },
  {   -64, 5,  5,              0x01b },
  {    32, 5,  5,              0x01c },
  {    64, 5,  6,              0x01d },
  { -1025, 5, jbig2HuffmanLOW, 0x01e },
  {  2048, 5, 32,              0x01f },
  {     0, 0, jbig2HuffmanEOT, 0     }
};

JBIG2HuffmanTable huffTableH[] = {
  {     0, 2,  1,              0x000 },
  {     0, 2, jbig2HuffmanOOB, 0x001 },
  {     4, 3,  4,              0x004 },
  {    -1, 4,  0,              0x00a },
  {    22, 4,  4,              0x00b },
  {    38, 4,  5,              0x00c },
  {     2, 5,  0,              0x01a },
  {    70, 5,  6,              0x01b },
  {   134, 5,  7,              0x01c },
  {     3, 6,  0,              0x03a },
  {    20, 6,  1,              0x03b },
  {   262, 6,  7,              0x03c },
  {   646, 6, 10,              0x03d },
  {    -2, 7,  0,              0x07c },
  {   390, 7,  8,              0x07d },
  {   -15, 8,  3,              0x0fc },
  {    -5, 8,  1,              0x0fd },
  {    -7, 9,  1,              0x1fc },
  {    -3, 9,  0,              0x1fd },
  {   -16, 9, jbig2HuffmanLOW, 0x1fe },
  {  1670, 9, 32,              0x1ff },
  {     0, 0, jbig2HuffmanEOT, 0     }
};

JBIG2HuffmanTable huffTableI[] = {
  {     0, 2, jbig2HuffmanOOB, 0x000 },
  {    -1, 3,  1,              0x002 },
  {     1, 3,  1,              0x003 },
  {     7, 3,  5,              0x004 },
  {    -3, 4,  1,              0x00a },
  {    43, 4,  5,              0x00b },
  {    75, 4,  6,              0x00c },
  {     3, 5,  1,              0x01a },
  {   139, 5,  7,              0x01b },
  {   267, 5,  8,              0x01c },
  {     5, 6,  1,              0x03a },
  {    39, 6,  2,              0x03b },
  {   523, 6,  8,              0x03c },
  {  1291, 6, 11,              0x03d },
  {    -5, 7,  1,              0x07c },
  {   779, 7,  9,              0x07d },
  {   -31, 8,  4,              0x0fc },
  {   -11, 8,  2,              0x0fd },
  {   -15, 9,  2,              0x1fc },
  {    -7, 9,  1,              0x1fd },
  {   -32, 9, jbig2HuffmanLOW, 0x1fe },
  {  3339, 9, 32,              0x1ff },
  {     0, 0, jbig2HuffmanEOT, 0     }
};

JBIG2HuffmanTable huffTableJ[] = {
  {    -2, 2,  2,              0x000 },
  {     6, 2,  6,              0x001 },
  {     0, 2, jbig2HuffmanOOB, 0x002 },
  {    -3, 5,  0,              0x018 },
  {     2, 5,  0,              0x019 },
  {    70, 5,  5,              0x01a },
  {     3, 6,  0,              0x036 },
  {   102, 6,  5,              0x037 },
  {   134, 6,  6,              0x038 },
  {   198, 6,  7,              0x039 },
  {   326, 6,  8,              0x03a },
  {   582, 6,  9,              0x03b },
  {  1094, 6, 10,              0x03c },
  {   -21, 7,  4,              0x07a },
  {    -4, 7,  0,              0x07b },
  {     4, 7,  0,              0x07c },
  {  2118, 7, 11,              0x07d },
  {    -5, 8,  0,              0x0fc },
  {     5, 8,  0,              0x0fd },
  {   -22, 8, jbig2HuffmanLOW, 0x0fe },
  {  4166, 8, 32,              0x0ff },
  {     0, 0, jbig2HuffmanEOT, 0     }
};

JBIG2HuffmanTable huffTableK[] = {
  {     1, 1,  0,              0x000 },
  {     2, 2,  1,              0x002 },
  {     4, 4,  0,              0x00c },
  {     5, 4,  1,              0x00d },
  {     7, 5,  1,              0x01c },
  {     9, 5,  2,              0x01d },
  {    13, 6,  2,              0x03c },
  {    17, 7,  2,              0x07a },
  {    21, 7,  3,              0x07b },
  {    29, 7,  4,              0x07c },
  {    45, 7,  5,              0x07d },
  {    77, 7,  6,              0x07e },
  {   141, 7, 32,              0x07f },
  {     0, 0, jbig2HuffmanEOT, 0     }
};

JBIG2HuffmanTable huffTableL[] = {
  {     1, 1,  0,              0x000 },
  {     2, 2,  0,              0x002 },
  {     3, 3,  1,              0x006 },
  {     5, 5,  0,              0x01c },
  {     6, 5,  1,              0x01d },
  {     8, 6,  1,              0x03c },
  {    10, 7,  0,              0x07a },
  {    11, 7,  1,              0x07b },
  {    13, 7,  2,              0x07c },
  {    17, 7,  3,              0x07d },
  {    25, 7,  4,              0x07e },
  {    41, 8,  5,              0x0fe },
  {    73, 8, 32,              0x0ff },
  {     0, 0, jbig2HuffmanEOT, 0     }
};

JBIG2HuffmanTable huffTableM[] = {
  {     1, 1,  0,              0x000 },
  {     2, 3,  0,              0x004 },
  {     7, 3,  3,              0x005 },
  {     3, 4,  0,              0x00c },
  {     5, 4,  1,              0x00d },
  {     4, 5,  0,              0x01c },
  {    15, 6,  1,              0x03a },
  {    17, 6,  2,              0x03b },
  {    21, 6,  3,              0x03c },
  {    29, 6,  4,              0x03d },
  {    45, 6,  5,              0x03e },
  {    77, 7,  6,              0x07e },
  {   141, 7, 32,              0x07f },
  {     0, 0, jbig2HuffmanEOT, 0     }
};

JBIG2HuffmanTable huffTableN[] = {
  {     0, 1,  0,              0x000 },
  {    -2, 3,  0,              0x004 },
  {    -1, 3,  0,              0x005 },
  {     1, 3,  0,              0x006 },
  {     2, 3,  0,              0x007 },
  {     0, 0, jbig2HuffmanEOT, 0     }
};

JBIG2HuffmanTable huffTableO[] = {
  {     0, 1,  0,              0x000 },
  {    -1, 3,  0,              0x004 },
  {     1, 3,  0,              0x005 },
  {    -2, 4,  0,              0x00c },
  {     2, 4,  0,              0x00d },
  {    -4, 5,  1,              0x01c },
  {     3, 5,  1,              0x01d },
  {    -8, 6,  2,              0x03c },
  {     5, 6,  2,              0x03d },
  {   -24, 7,  4,              0x07c },
  {     9, 7,  4,              0x07d },
  {   -25, 7, jbig2HuffmanLOW, 0x07e },
  {    25, 7, 32,              0x07f },
  {     0, 0, jbig2HuffmanEOT, 0     }
};

//------------------------------------------------------------------------
// JBIG2HuffmanDecoder
//------------------------------------------------------------------------

class JBIG2HuffmanDecoder {
public:

  JBIG2HuffmanDecoder();
  ~JBIG2HuffmanDecoder();
  void setStream(Stream *strA) { str = strA; }

  void reset();

  // Returns false for OOB, otherwise sets *<x> and returns true.
  GBool decodeInt(int *x, JBIG2HuffmanTable *table);

  Guint readBits(Guint n);
  Guint readBit();

  // Sort the table by prefix length and assign prefix values.
  void buildTable(JBIG2HuffmanTable *table, Guint len);

private:

  Stream *str;
  Guint buf;
  Guint bufLen;
};

JBIG2HuffmanDecoder::JBIG2HuffmanDecoder() {
  str = NULL;
  reset();
}

JBIG2HuffmanDecoder::~JBIG2HuffmanDecoder() {
}

void JBIG2HuffmanDecoder::reset() {
  buf = 0;
  bufLen = 0;
}

//~ optimize this
GBool JBIG2HuffmanDecoder::decodeInt(int *x, JBIG2HuffmanTable *table) {
  Guint i, len, prefix;

  i = 0;
  len = 0;
  prefix = 0;
  while (table[i].rangeLen != jbig2HuffmanEOT) {
    while (len < table[i].prefixLen) {
      prefix = (prefix << 1) | readBit();
      ++len;
    }
    if (prefix == table[i].prefix) {
      if (table[i].rangeLen == jbig2HuffmanOOB) {
	return gFalse;
      }
      if (table[i].rangeLen == jbig2HuffmanLOW) {
	*x = table[i].val - readBits(32);
      } else if (table[i].rangeLen > 0) {
	*x = table[i].val + readBits(table[i].rangeLen);
      } else {
	*x = table[i].val;
      }
      return gTrue;
    }
    ++i;
  }
  return gFalse;
}

Guint JBIG2HuffmanDecoder::readBits(Guint n) {
  Guint x, mask, nLeft;

  mask = (n == 32) ? 0xffffffff : ((1 << n) - 1);
  if (bufLen >= n) {
    x = (buf >> (bufLen - n)) & mask;
    bufLen -= n;
  } else {
    x = buf & ((1 << bufLen) - 1);
    nLeft = n - bufLen;
    bufLen = 0;
    while (nLeft >= 8) {
      x = (x << 8) | (str->getChar() & 0xff);
      nLeft -= 8;
    }
    if (nLeft > 0) {
      buf = str->getChar();
      bufLen = 8 - nLeft;
      x = (x << nLeft) | ((buf >> bufLen) & ((1 << nLeft) - 1));
    }
  }
  return x;
}

Guint JBIG2HuffmanDecoder::readBit() {
  if (bufLen == 0) {
    buf = str->getChar();
    bufLen = 8;
  }
  --bufLen;
  return (buf >> bufLen) & 1;
}

void JBIG2HuffmanDecoder::buildTable(JBIG2HuffmanTable *table, Guint len) {
  Guint i, j, k, prefix;
  JBIG2HuffmanTable tab;

  // stable selection sort:
  // - entries with prefixLen > 0, in ascending prefixLen order
  // - entry with prefixLen = 0, rangeLen = EOT
  // - all other entries with prefixLen = 0
  // (on entry, table[len] has prefixLen = 0, rangeLen = EOT)
  for (i = 0; i < len; ++i) {
    for (j = i; j < len && table[j].prefixLen == 0; ++j) ;
    if (j == len) {
      break;
    }
    for (k = j + 1; k < len; ++k) {
      if (table[k].prefixLen > 0 &&
	  table[k].prefixLen < table[j].prefixLen) {
	j = k;
      }
    }
    if (j != i) {
      tab = table[j];
      for (k = j; k > i; --k) {
	table[k] = table[k - 1];
      }
      table[i] = tab;
    }
  }
  table[i] = table[len];

  // assign prefixes
  i = 0;
  prefix = 0;
  table[i++].prefix = prefix++;
  for (; table[i].rangeLen != jbig2HuffmanEOT; ++i) {
    prefix <<= table[i].prefixLen - table[i-1].prefixLen;
    table[i].prefix = prefix++;
  }
}

//------------------------------------------------------------------------
// JBIG2MMRDecoder
//------------------------------------------------------------------------

class JBIG2MMRDecoder {
public:

  JBIG2MMRDecoder();
  ~JBIG2MMRDecoder();
  void setStream(Stream *strA) { str = strA; }
  void reset();
  int get2DCode();
  int getBlackCode();
  int getWhiteCode();
  Guint get24Bits();
  void skipTo(Guint length);

private:

  Stream *str;
  Guint buf;
  Guint bufLen;
  Guint nBytesRead;
};

JBIG2MMRDecoder::JBIG2MMRDecoder() {
  str = NULL;
  reset();
}

JBIG2MMRDecoder::~JBIG2MMRDecoder() {
}

void JBIG2MMRDecoder::reset() {
  buf = 0;
  bufLen = 0;
  nBytesRead = 0;
}

int JBIG2MMRDecoder::get2DCode() {
  CCITTCode *p;

  if (bufLen == 0) {
    buf = str->getChar() & 0xff;
    bufLen = 8;
    ++nBytesRead;
    p = &twoDimTab1[(buf >> 1) & 0x7f];
  } else if (bufLen == 8) {
    p = &twoDimTab1[(buf >> 1) & 0x7f];
  } else {
    p = &twoDimTab1[(buf << (7 - bufLen)) & 0x7f];
    if (p->bits < 0 || p->bits > (int)bufLen) {
      buf = (buf << 8) | (str->getChar() & 0xff);
      bufLen += 8;
      ++nBytesRead;
      p = &twoDimTab1[(buf >> (bufLen - 7)) & 0x7f];
    }
  }
  if (p->bits < 0) {
    error(str->getPos(), "Bad two dim code in JBIG2 MMR stream");
    return 0;
  }
  bufLen -= p->bits;
  return p->n;
}

int JBIG2MMRDecoder::getWhiteCode() {
  CCITTCode *p;
  Guint code;

  if (bufLen == 0) {
    buf = str->getChar() & 0xff;
    bufLen = 8;
    ++nBytesRead;
  }
  while (1) {
    if (bufLen >= 7 && ((buf >> (bufLen - 7)) & 0x7f) == 0) {