jpxstream.cc

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

#include <aconf.h>

#ifdef USE_GCC_PRAGMAS
#pragma implementation
#endif

#include <limits.h>
#include "gmem.h"
#include "Error.h"
#include "JArithmeticDecoder.h"
#include "JPXStream.h"

//~ to do:
//  - precincts
//  - ROI
//  - progression order changes
//  - packed packet headers
//  - support for palettes, channel maps, etc.
//  - make sure all needed JP2/JPX subboxes are parsed (readBoxes)
//  - can we assume that QCC segments must come after the QCD segment?
//  - skip EPH markers (readTilePartData)
//  - handle tilePartToEOC in readTilePartData
//  - deal with multiple codeword segments (readTilePartData,
//    readCodeBlockData)
//  - progression orders 2, 3, and 4
//  - in coefficient decoding (readCodeBlockData):
//    - termination pattern: terminate after every coding pass
//    - error resilience segmentation symbol
//    - selective arithmetic coding bypass
//    - vertically causal context formation
//    - coeffs longer than 31 bits (should just ignore the extra bits?)
//  - handle boxes larger than 2^32 bytes
//  - the fixed-point arithmetic won't handle 16-bit pixels

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

// number of contexts for the arithmetic decoder
#define jpxNContexts        19

#define jpxContextSigProp    0	// 0 - 8: significance prop and cleanup
#define jpxContextSign       9	// 9 - 13: sign
#define jpxContextMagRef    14	// 14 -16: magnitude refinement
#define jpxContextRunLength 17	// cleanup: run length
#define jpxContextUniform   18	// cleanup: first signif coeff

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

#define jpxPassSigProp       0
#define jpxPassMagRef        1
#define jpxPassCleanup       2

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

// arithmetic decoder context for the significance propagation and
// cleanup passes:
//     [horiz][vert][diag][subband]
// where subband = 0 for HL
//               = 1 for LH and LL
//               = 2 for HH
static Guint sigPropContext[3][3][5][3] = {
  {{{ 0, 0, 0 },   // horiz=0, vert=0, diag=0
    { 1, 1, 3 },   // horiz=0, vert=0, diag=1
    { 2, 2, 6 },   // horiz=0, vert=0, diag=2
    { 2, 2, 8 },   // horiz=0, vert=0, diag=3
    { 2, 2, 8 }},  // horiz=0, vert=0, diag=4
   {{ 5, 3, 1 },   // horiz=0, vert=1, diag=0
    { 6, 3, 4 },   // horiz=0, vert=1, diag=1
    { 6, 3, 7 },   // horiz=0, vert=1, diag=2
    { 6, 3, 8 },   // horiz=0, vert=1, diag=3
    { 6, 3, 8 }},  // horiz=0, vert=1, diag=4
   {{ 8, 4, 2 },   // horiz=0, vert=2, diag=0
    { 8, 4, 5 },   // horiz=0, vert=2, diag=1
    { 8, 4, 7 },   // horiz=0, vert=2, diag=2
    { 8, 4, 8 },   // horiz=0, vert=2, diag=3
    { 8, 4, 8 }}}, // horiz=0, vert=2, diag=4
  {{{ 3, 5, 1 },   // horiz=1, vert=0, diag=0
    { 3, 6, 4 },   // horiz=1, vert=0, diag=1
    { 3, 6, 7 },   // horiz=1, vert=0, diag=2
    { 3, 6, 8 },   // horiz=1, vert=0, diag=3
    { 3, 6, 8 }},  // horiz=1, vert=0, diag=4
   {{ 7, 7, 2 },   // horiz=1, vert=1, diag=0
    { 7, 7, 5 },   // horiz=1, vert=1, diag=1
    { 7, 7, 7 },   // horiz=1, vert=1, diag=2
    { 7, 7, 8 },   // horiz=1, vert=1, diag=3
    { 7, 7, 8 }},  // horiz=1, vert=1, diag=4
   {{ 8, 7, 2 },   // horiz=1, vert=2, diag=0
    { 8, 7, 5 },   // horiz=1, vert=2, diag=1
    { 8, 7, 7 },   // horiz=1, vert=2, diag=2
    { 8, 7, 8 },   // horiz=1, vert=2, diag=3
    { 8, 7, 8 }}}, // horiz=1, vert=2, diag=4
  {{{ 4, 8, 2 },   // horiz=2, vert=0, diag=0
    { 4, 8, 5 },   // horiz=2, vert=0, diag=1
    { 4, 8, 7 },   // horiz=2, vert=0, diag=2
    { 4, 8, 8 },   // horiz=2, vert=0, diag=3
    { 4, 8, 8 }},  // horiz=2, vert=0, diag=4
   {{ 7, 8, 2 },   // horiz=2, vert=1, diag=0
    { 7, 8, 5 },   // horiz=2, vert=1, diag=1
    { 7, 8, 7 },   // horiz=2, vert=1, diag=2
    { 7, 8, 8 },   // horiz=2, vert=1, diag=3
    { 7, 8, 8 }},  // horiz=2, vert=1, diag=4
   {{ 8, 8, 2 },   // horiz=2, vert=2, diag=0
    { 8, 8, 5 },   // horiz=2, vert=2, diag=1
    { 8, 8, 7 },   // horiz=2, vert=2, diag=2
    { 8, 8, 8 },   // horiz=2, vert=2, diag=3
    { 8, 8, 8 }}}  // horiz=2, vert=2, diag=4
};

// arithmetic decoder context and xor bit for the sign bit in the
// significance propagation pass:
//     [horiz][vert][k]
// where horiz/vert are offset by 2 (i.e., range is -2 .. 2)
// and k = 0 for the context
//       = 1 for the xor bit
static Guint signContext[5][5][2] = {
  {{ 13, 1 },  // horiz=-2, vert=-2
   { 13, 1 },  // horiz=-2, vert=-1
   { 12, 1 },  // horiz=-2, vert= 0
   { 11, 1 },  // horiz=-2, vert=+1
   { 11, 1 }}, // horiz=-2, vert=+2
  {{ 13, 1 },  // horiz=-1, vert=-2
   { 13, 1 },  // horiz=-1, vert=-1
   { 12, 1 },  // horiz=-1, vert= 0
   { 11, 1 },  // horiz=-1, vert=+1
   { 11, 1 }}, // horiz=-1, vert=+2
  {{ 10, 1 },  // horiz= 0, vert=-2
   { 10, 1 },  // horiz= 0, vert=-1
   {  9, 0 },  // horiz= 0, vert= 0
   { 10, 0 },  // horiz= 0, vert=+1
   { 10, 0 }}, // horiz= 0, vert=+2
  {{ 11, 0 },  // horiz=+1, vert=-2
   { 11, 0 },  // horiz=+1, vert=-1
   { 12, 0 },  // horiz=+1, vert= 0
   { 13, 0 },  // horiz=+1, vert=+1
   { 13, 0 }}, // horiz=+1, vert=+2
  {{ 11, 0 },  // horiz=+2, vert=-2
   { 11, 0 },  // horiz=+2, vert=-1
   { 12, 0 },  // horiz=+2, vert= 0
   { 13, 0 },  // horiz=+2, vert=+1
   { 13, 0 }}, // horiz=+2, vert=+2
};

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

// constants used in the IDWT
#define idwtAlpha  -1.586134342059924
#define idwtBeta   -0.052980118572961
#define idwtGamma   0.882911075530934
#define idwtDelta   0.443506852043971
#define idwtKappa   1.230174104914001
#define idwtIKappa  (1.0 / idwtKappa)

// number of bits to the right of the decimal point for the fixed
// point arithmetic used in the IDWT
#define fracBits 16

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

// floor(x / y)
#define jpxFloorDiv(x, y) ((x) / (y))

// floor(x / 2^y)
#define jpxFloorDivPow2(x, y) ((x) >> (y))

// ceil(x / y)
#define jpxCeilDiv(x, y) (((x) + (y) - 1) / (y))

// ceil(x / 2^y)
#define jpxCeilDivPow2(x, y) (((x) + (1 << (y)) - 1) >> (y))

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

#if 1 //----- disable coverage tracking

#define cover(idx)

#else //----- enable coverage tracking

class JPXCover {
public:

  JPXCover(int sizeA);
  ~JPXCover();
  void incr(int idx);

private:

  int size, used;
  int *data;
};

JPXCover::JPXCover(int sizeA) {
  size = sizeA;
  used = -1;
  data = (int *)gmallocn(size, sizeof(int));
  memset(data, 0, size * sizeof(int));
}

JPXCover::~JPXCover() {
  int i;

  printf("JPX coverage:\n");
  for (i = 0; i <= used; ++i) {
    printf("  %4d: %8d\n", i, data[i]);
  }
  gfree(data);
}

void JPXCover::incr(int idx) {
  if (idx < size) {
    ++data[idx];
    if (idx > used) {
      used = idx;
    }
  }
}

JPXCover jpxCover(150);

#define cover(idx) jpxCover.incr(idx)

#endif //----- coverage tracking

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

JPXStream::JPXStream(Stream *strA):
  FilterStream(strA)
{
  nComps = 0;
  bpc = NULL;
  width = height = 0;
  haveCS = gFalse;
  havePalette = gFalse;
  haveCompMap = gFalse;
  haveChannelDefn = gFalse;

  img.tiles = NULL;
  bitBuf = 0;
  bitBufLen = 0;
  bitBufSkip = gFalse;
  byteCount = 0;
}

JPXStream::~JPXStream() {
  close();
  delete str;
}

void JPXStream::reset() {
  str->reset();
  if (readBoxes()) {
    curY = img.yOffset;
  } else {
    // readBoxes reported an error, so we go immediately to EOF
    curY = img.ySize;
  }
  curX = img.xOffset;
  curComp = 0;
  readBufLen = 0;
}

void JPXStream::close() {
  JPXTile *tile;
  JPXTileComp *tileComp;
  JPXResLevel *resLevel;
  JPXPrecinct *precinct;
  JPXSubband *subband;
  JPXCodeBlock *cb;
  Guint comp, i, k, r, pre, sb;

  gfree(bpc);
  bpc = NULL;
  if (havePalette) {
    gfree(palette.bpc);
    gfree(palette.c);
    havePalette = gFalse;
  }
  if (haveCompMap) {
    gfree(compMap.comp);
    gfree(compMap.type);
    gfree(compMap.pComp);
    haveCompMap = gFalse;
  }
  if (haveChannelDefn) {
    gfree(channelDefn.idx);
    gfree(channelDefn.type);
    gfree(channelDefn.assoc);
    haveChannelDefn = gFalse;
  }

  if (img.tiles) {
    for (i = 0; i < img.nXTiles * img.nYTiles; ++i) {
      tile = &img.tiles[i];
      if (tile->tileComps) {
	for (comp = 0; comp < img.nComps; ++comp) {
	  tileComp = &tile->tileComps[comp];
	  gfree(tileComp->quantSteps);
	  gfree(tileComp->data);
	  gfree(tileComp->buf);
	  if (tileComp->resLevels) {
	    for (r = 0; r <= tileComp->nDecompLevels; ++r) {
	      resLevel = &tileComp->resLevels[r];
	      if (resLevel->precincts) {
		for (pre = 0; pre < 1; ++pre) {
		  precinct = &resLevel->precincts[pre];
		  if (precinct->subbands) {
		    for (sb = 0; sb < (Guint)(r == 0 ? 1 : 3); ++sb) {
		      subband = &precinct->subbands[sb];
		      gfree(subband->inclusion);
		      gfree(subband->zeroBitPlane);
		      if (subband->cbs) {
			for (k = 0; k < subband->nXCBs * subband->nYCBs; ++k) {
			  cb = &subband->cbs[k];
			  gfree(cb->coeffs);
			  if (cb->arithDecoder) {
			    delete cb->arithDecoder;
			  }
			  if (cb->stats) {
			    delete cb->stats;
			  }
			}
			gfree(subband->cbs);
		      }
		    }
		    gfree(precinct->subbands);
		  }
		}
		gfree(img.tiles[i].tileComps[comp].resLevels[r].precincts);
	      }
	    }
	    gfree(img.tiles[i].tileComps[comp].resLevels);
	  }
	}
	gfree(img.tiles[i].tileComps);
      }
    }
    gfree(img.tiles);
    img.tiles = NULL;
  }
  FilterStream::close();
}

int JPXStream::getChar() {
  int c;

  if (readBufLen < 8) {
    fillReadBuf();
  }
  if (readBufLen == 8) {
    c = readBuf & 0xff;
    readBufLen = 0;
  } else if (readBufLen > 8) {
    c = (readBuf >> (readBufLen - 8)) & 0xff;
    readBufLen -= 8;
  } else if (readBufLen == 0) {
    c = EOF;
  } else {
    c = (readBuf << (8 - readBufLen)) & 0xff;
    readBufLen = 0;
  }
  return c;
}

int JPXStream::lookChar() {
  int c;

  if (readBufLen < 8) {
    fillReadBuf();
  }
  if (readBufLen == 8) {
    c = readBuf & 0xff;
  } else if (readBufLen > 8) {
    c = (readBuf >> (readBufLen - 8)) & 0xff;
  } else if (readBufLen == 0) {
    c = EOF;
  } else {
    c = (readBuf << (8 - readBufLen)) & 0xff;
  }
  return c;
}

void JPXStream::fillReadBuf() {
  JPXTileComp *tileComp;
  Guint tileIdx, tx, ty;
  int pix, pixBits;

  do {
    if (curY >= img.ySize) {
      return;
    }
    tileIdx = ((curY - img.yTileOffset) / img.yTileSize) * img.nXTiles
              + (curX - img.xTileOffset) / img.xTileSize;
#if 1 //~ ignore the palette, assume the PDF ColorSpace object is valid
    tileComp = &img.tiles[tileIdx].tileComps[curComp];
#else
    tileComp = &img.tiles[tileIdx].tileComps[havePalette ? 0 : curComp];
#endif
    tx = jpxCeilDiv((curX - img.xTileOffset) % img.xTileSize, tileComp->hSep);
    ty = jpxCeilDiv((curY - img.yTileOffset) % img.yTileSize, tileComp->vSep);
    pix = (int)tileComp->data[ty * (tileComp->x1 - tileComp->x0) + tx];
    pixBits = tileComp->prec;
#if 1 //~ ignore the palette, assume the PDF ColorSpace object is valid
    if (++curComp == img.nComps) {
#else
    if (havePalette) {
      if (pix >= 0 && pix < palette.nEntries) {
	pix = palette.c[pix * palette.nComps + curComp];
      } else {
	pix = 
      pixBits = palette.bpc[curComp];
    }
    if (++curComp == (Guint)(havePalette ? palette.nComps : img.nComps)) {
#endif
      curComp = 0;
      if (++curX == img.xSize) {
	curX = img.xOffset;
	++curY;
      }
    }