gfxstate.cc

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  for (i = 0; i < length; i++) {
    out[i] = 
      (in[i * 3 + 0] * 19595 + 
       in[i * 3 + 1] * 38469 + 
       in[i * 3 + 2] * 7472) / 65536;
  }
}

void GfxCalRGBColorSpace::getRGB(GfxColor *color, GfxRGB *rgb) {
  rgb->r = clip01(color->c[0]);
  rgb->g = clip01(color->c[1]);
  rgb->b = clip01(color->c[2]);
}

void GfxCalRGBColorSpace::getRGBLine(Guchar *in, unsigned int *out,
				     int length) {
  Guchar *p;
  int i;

  for (i = 0, p = in; i < length; i++, p += 3)
    out[i] = (p[0] << 16) | (p[1] << 8) | (p[2] << 0);
}

void GfxCalRGBColorSpace::getCMYK(GfxColor *color, GfxCMYK *cmyk) {
  GfxColorComp c, m, y, k;

  c = clip01(gfxColorComp1 - color->c[0]);
  m = clip01(gfxColorComp1 - color->c[1]);
  y = clip01(gfxColorComp1 - color->c[2]);
  k = c;
  if (m < k) {
    k = m;
  }
  if (y < k) {
    k = y;
  }
  cmyk->c = c - k;
  cmyk->m = m - k;
  cmyk->y = y - k;
  cmyk->k = k;
}

//------------------------------------------------------------------------
// GfxDeviceCMYKColorSpace
//------------------------------------------------------------------------

GfxDeviceCMYKColorSpace::GfxDeviceCMYKColorSpace() {
}

GfxDeviceCMYKColorSpace::~GfxDeviceCMYKColorSpace() {
}

GfxColorSpace *GfxDeviceCMYKColorSpace::copy() {
  return new GfxDeviceCMYKColorSpace();
}

void GfxDeviceCMYKColorSpace::getGray(GfxColor *color, GfxGray *gray) {
  *gray = clip01((GfxColorComp)(gfxColorComp1 - color->c[3]
				- 0.3  * color->c[0]
				- 0.59 * color->c[1]
				- 0.11 * color->c[2] + 0.5));
}

void GfxDeviceCMYKColorSpace::getRGB(GfxColor *color, GfxRGB *rgb) {
  double c, m, y, k, c1, m1, y1, k1, r, g, b, x;
    
  c = colToDbl(color->c[0]);
  m = colToDbl(color->c[1]);
  y = colToDbl(color->c[2]);
  k = colToDbl(color->c[3]);
  c1 = 1 - c;
  m1 = 1 - m;
  y1 = 1 - y;
  k1 = 1 - k;
  // this is a matrix multiplication, unrolled for performance
  //                        C M Y K
  x = c1 * m1 * y1 * k1; // 0 0 0 0
  r = g = b = x;
  x = c1 * m1 * y1 * k;  // 0 0 0 1
  r += 0.1373 * x;
  g += 0.1216 * x;
  b += 0.1255 * x;
  x = c1 * m1 * y  * k1; // 0 0 1 0
  r += x;
  g += 0.9490 * x;
  x = c1 * m1 * y  * k;  // 0 0 1 1
  r += 0.1098 * x;
  g += 0.1020 * x;
  x = c1 * m  * y1 * k1; // 0 1 0 0
  r += 0.9255 * x;
  b += 0.5490 * x;
  x = c1 * m  * y1 * k;  // 0 1 0 1
  r += 0.1412 * x;
  x = c1 * m  * y  * k1; // 0 1 1 0
  r += 0.9294 * x;
  g += 0.1098 * x;
  b += 0.1412 * x;
  x = c1 * m  * y  * k;  // 0 1 1 1
  r += 0.1333 * x;
  x = c  * m1 * y1 * k1; // 1 0 0 0
  g += 0.6784 * x;
  b += 0.9373 * x;
  x = c  * m1 * y1 * k;  // 1 0 0 1
  g += 0.0588 * x;
  b += 0.1412 * x;
  x = c  * m1 * y  * k1; // 1 0 1 0
  g += 0.6510 * x;
  b += 0.3137 * x;
  x = c  * m1 * y  * k;  // 1 0 1 1
  g += 0.0745 * x;
  x = c  * m  * y1 * k1; // 1 1 0 0
  r += 0.1804 * x;
  g += 0.1922 * x;
  b += 0.5725 * x;
  x = c  * m  * y1 * k;  // 1 1 0 1
  b += 0.0078 * x;
  x = c  * m  * y  * k1; // 1 1 1 0
  r += 0.2118 * x;
  g += 0.2119 * x;
  b += 0.2235 * x;
  rgb->r = clip01(dblToCol(r));
  rgb->g = clip01(dblToCol(g));
  rgb->b = clip01(dblToCol(b));
}

void GfxDeviceCMYKColorSpace::getCMYK(GfxColor *color, GfxCMYK *cmyk) {
  cmyk->c = clip01(color->c[0]);
  cmyk->m = clip01(color->c[1]);
  cmyk->y = clip01(color->c[2]);
  cmyk->k = clip01(color->c[3]);
}

//------------------------------------------------------------------------
// GfxLabColorSpace
//------------------------------------------------------------------------

// This is the inverse of MatrixLMN in Example 4.10 from the PostScript
// Language Reference, Third Edition.
static double xyzrgb[3][3] = {
  {  3.240449, -1.537136, -0.498531 },
  { -0.969265,  1.876011,  0.041556 },
  {  0.055643, -0.204026,  1.057229 }
};

GfxLabColorSpace::GfxLabColorSpace() {
  whiteX = whiteY = whiteZ = 1;
  blackX = blackY = blackZ = 0;
  aMin = bMin = -100;
  aMax = bMax = 100;
}

GfxLabColorSpace::~GfxLabColorSpace() {
}

GfxColorSpace *GfxLabColorSpace::copy() {
  GfxLabColorSpace *cs;

  cs = new GfxLabColorSpace();
  cs->whiteX = whiteX;
  cs->whiteY = whiteY;
  cs->whiteZ = whiteZ;
  cs->blackX = blackX;
  cs->blackY = blackY;
  cs->blackZ = blackZ;
  cs->aMin = aMin;
  cs->aMax = aMax;
  cs->bMin = bMin;
  cs->bMax = bMax;
  cs->kr = kr;
  cs->kg = kg;
  cs->kb = kb;
  return cs;
}

GfxColorSpace *GfxLabColorSpace::parse(Array *arr) {
  GfxLabColorSpace *cs;
  Object obj1, obj2, obj3;

  arr->get(1, &obj1);
  if (!obj1.isDict()) {
    error(-1, "Bad Lab color space");
    obj1.free();
    return NULL;
  }
  cs = new GfxLabColorSpace();
  if (obj1.dictLookup("WhitePoint", &obj2)->isArray() &&
      obj2.arrayGetLength() == 3) {
    obj2.arrayGet(0, &obj3);
    cs->whiteX = obj3.getNum();
    obj3.free();
    obj2.arrayGet(1, &obj3);
    cs->whiteY = obj3.getNum();
    obj3.free();
    obj2.arrayGet(2, &obj3);
    cs->whiteZ = obj3.getNum();
    obj3.free();
  }
  obj2.free();
  if (obj1.dictLookup("BlackPoint", &obj2)->isArray() &&
      obj2.arrayGetLength() == 3) {
    obj2.arrayGet(0, &obj3);
    cs->blackX = obj3.getNum();
    obj3.free();
    obj2.arrayGet(1, &obj3);
    cs->blackY = obj3.getNum();
    obj3.free();
    obj2.arrayGet(2, &obj3);
    cs->blackZ = obj3.getNum();
    obj3.free();
  }
  obj2.free();
  if (obj1.dictLookup("Range", &obj2)->isArray() &&
      obj2.arrayGetLength() == 4) {
    obj2.arrayGet(0, &obj3);
    cs->aMin = obj3.getNum();
    obj3.free();
    obj2.arrayGet(1, &obj3);
    cs->aMax = obj3.getNum();
    obj3.free();
    obj2.arrayGet(2, &obj3);
    cs->bMin = obj3.getNum();
    obj3.free();
    obj2.arrayGet(3, &obj3);
    cs->bMax = obj3.getNum();
    obj3.free();
  }
  obj2.free();
  obj1.free();

  cs->kr = 1 / (xyzrgb[0][0] * cs->whiteX +
		xyzrgb[0][1] * cs->whiteY +
		xyzrgb[0][2] * cs->whiteZ);
  cs->kg = 1 / (xyzrgb[1][0] * cs->whiteX +
		xyzrgb[1][1] * cs->whiteY +
		xyzrgb[1][2] * cs->whiteZ);
  cs->kb = 1 / (xyzrgb[2][0] * cs->whiteX +
		xyzrgb[2][1] * cs->whiteY +
		xyzrgb[2][2] * cs->whiteZ);

  return cs;
}

void GfxLabColorSpace::getGray(GfxColor *color, GfxGray *gray) {
  GfxRGB rgb;

  getRGB(color, &rgb);
  *gray = clip01((GfxColorComp)(0.299 * rgb.r +
		 0.587 * rgb.g +
				0.114 * rgb.b + 0.5));
}

void GfxLabColorSpace::getRGB(GfxColor *color, GfxRGB *rgb) {
  double X, Y, Z;
  double t1, t2;
  double r, g, b;

  // convert L*a*b* to CIE 1931 XYZ color space
  t1 = (colToDbl(color->c[0]) + 16) / 116;
  t2 = t1 + colToDbl(color->c[1]) / 500;
  if (t2 >= (6.0 / 29.0)) {
    X = t2 * t2 * t2;
  } else {
    X = (108.0 / 841.0) * (t2 - (4.0 / 29.0));
  }
  X *= whiteX;
  if (t1 >= (6.0 / 29.0)) {
    Y = t1 * t1 * t1;
  } else {
    Y = (108.0 / 841.0) * (t1 - (4.0 / 29.0));
  }
  Y *= whiteY;
  t2 = t1 - colToDbl(color->c[2]) / 200;
  if (t2 >= (6.0 / 29.0)) {
    Z = t2 * t2 * t2;
  } else {
    Z = (108.0 / 841.0) * (t2 - (4.0 / 29.0));
  }
  Z *= whiteZ;

  // convert XYZ to RGB, including gamut mapping and gamma correction
  r = xyzrgb[0][0] * X + xyzrgb[0][1] * Y + xyzrgb[0][2] * Z;
  g = xyzrgb[1][0] * X + xyzrgb[1][1] * Y + xyzrgb[1][2] * Z;
  b = xyzrgb[2][0] * X + xyzrgb[2][1] * Y + xyzrgb[2][2] * Z;
  rgb->r = dblToCol(pow(clip01(r * kr), 0.5));
  rgb->g = dblToCol(pow(clip01(g * kg), 0.5));
  rgb->b = dblToCol(pow(clip01(b * kb), 0.5));
}

void GfxLabColorSpace::getCMYK(GfxColor *color, GfxCMYK *cmyk) {
  GfxRGB rgb;
  GfxColorComp c, m, y, k;

  getRGB(color, &rgb);
  c = clip01(gfxColorComp1 - rgb.r);
  m = clip01(gfxColorComp1 - rgb.g);
  y = clip01(gfxColorComp1 - rgb.b);
  k = c;
  if (m < k) {
    k = m;
  }
  if (y < k) {
    k = y;
  }
  cmyk->c = c - k;
  cmyk->m = m - k;
  cmyk->y = y - k;
  cmyk->k = k;
}

void GfxLabColorSpace::getDefaultRanges(double *decodeLow, double *decodeRange,
					int maxImgPixel) {
  decodeLow[0] = 0;
  decodeRange[0] = 100;
  decodeLow[1] = aMin;
  decodeRange[1] = aMax - aMin;
  decodeLow[2] = bMin;
  decodeRange[2] = bMax - bMin;
}

//------------------------------------------------------------------------
// GfxICCBasedColorSpace
//------------------------------------------------------------------------

GfxICCBasedColorSpace::GfxICCBasedColorSpace(int nCompsA, GfxColorSpace *altA,
					     Ref *iccProfileStreamA) {
  nComps = nCompsA;
  alt = altA;
  iccProfileStream = *iccProfileStreamA;
  rangeMin[0] = rangeMin[1] = rangeMin[2] = rangeMin[3] = 0;
  rangeMax[0] = rangeMax[1] = rangeMax[2] = rangeMax[3] = 1;
}

GfxICCBasedColorSpace::~GfxICCBasedColorSpace() {
  delete alt;
}

GfxColorSpace *GfxICCBasedColorSpace::copy() {
  GfxICCBasedColorSpace *cs;
  int i;

  cs = new GfxICCBasedColorSpace(nComps, alt->copy(), &iccProfileStream);
  for (i = 0; i < 4; ++i) {
    cs->rangeMin[i] = rangeMin[i];
    cs->rangeMax[i] = rangeMax[i];
  }
  return cs;
}

GfxColorSpace *GfxICCBasedColorSpace::parse(Array *arr) {
  GfxICCBasedColorSpace *cs;
  Ref iccProfileStreamA;
  int nCompsA;
  GfxColorSpace *altA;
  Dict *dict;
  Object obj1, obj2, obj3;
  int i;

  arr->getNF(1, &obj1);
  if (obj1.isRef()) {
    iccProfileStreamA = obj1.getRef();
  } else {
    iccProfileStreamA.num = 0;
    iccProfileStreamA.gen = 0;
  }
  obj1.free();
  arr->get(1, &obj1);
  if (!obj1.isStream()) {
    error(-1, "Bad ICCBased color space (stream)");
    obj1.free();
    return NULL;
  }
  dict = obj1.streamGetDict();
  if (!dict->lookup("N", &obj2)->isInt()) {
    error(-1, "Bad ICCBased color space (N)");
    obj2.free();
    obj1.free();
    return NULL;
  }
  nCompsA = obj2.getInt();
  obj2.free();
  if (nCompsA > gfxColorMaxComps) {
    error(-1, "ICCBased color space with too many (%d > %d) components",
	  nCompsA, gfxColorMaxComps);
    nCompsA = gfxColorMaxComps;
  }
  if (dict->lookup("Alternate", &obj2)->isNull() ||
      !(altA = GfxColorSpace::parse(&obj2))) {
    switch (nCompsA) {
    case 1:
      altA = new GfxDeviceGrayColorSpace();
      break;
    case 3:
      altA = new GfxDeviceRGBColorSpace();
      break;
    case 4:
      altA = new GfxDeviceCMYKColorSpace();
      break;
    default:
      error(-1, "Bad ICCBased color space - invalid N");
      obj2.free();
      obj1.free();
      return NULL;
    }
  }
  obj2.free();
  cs = new GfxICCBasedColorSpace(nCompsA, altA, &iccProfileStreamA);
  if (dict->lookup("Range", &obj2)->isArray() &&
      obj2.arrayGetLength() == 2 * nCompsA) {
    for (i = 0; i < nCompsA; ++i) {
      obj2.arrayGet(2*i, &obj3);
      cs->rangeMin[i] = obj3.getNum();
      obj3.free();
      obj2.arrayGet(2*i+1, &obj3);
      cs->rangeMax[i] = obj3.getNum();
      obj3.free();
    }
  }
  obj2.free();
  obj1.free();
  return cs;
}

void GfxICCBasedColorSpace::getGray(GfxColor *color, GfxGray *gray) {
  alt->getGray(color, gray);
}

void GfxICCBasedColorSpace::getRGB(GfxColor *color, GfxRGB *rgb) {
  alt->getRGB(color, rgb);
}

void GfxICCBasedColorSpace::getRGBLine(Guchar *in, unsigned int *out,
				       int length) {
  alt->getRGBLine(in, out, length);
}

void GfxICCBasedColorSpace::getCMYK(GfxColor *color, GfxCMYK *cmyk) {
  alt->getCMYK(color, cmyk);
}

void GfxICCBasedColorSpace::getDefaultRanges(double *decodeLow,
					     double *decodeRange,
					     int maxImgPixel) {
  alt->getDefaultRanges(decodeLow, decodeRange, maxImgPixel);

#if 0
  // this is nominally correct, but some PDF files don't set the
  // correct ranges in the ICCBased dict
  int i;

  for (i = 0; i < nComps; ++i) {
    decodeLow[i] = rangeMin[i];
    decodeRange[i] = rangeMax[i] - rangeMin[i];
  }
#endif
}

//------------------------------------------------------------------------
// GfxIndexedColorSpace
//------------------------------------------------------------------------

GfxIndexedColorSpace::GfxIndexedColorSpace(GfxColorSpace *baseA,
					   int indexHighA) {
  base = baseA;
  indexHigh = indexHighA;
  lookup = (Guchar *)gmallocn((indexHigh + 1) * base->getNComps(),
			      sizeof(Guchar));
}

GfxIndexedColorSpace::~GfxIndexedColorSpace() {
  delete base;
  gfree(lookup);
}

GfxColorSpace *GfxIndexedColorSpace::copy() {
  GfxIndexedColorSpace *cs;

  cs = new GfxIndexedColorSpace(base->copy(), indexHigh);
  memcpy(cs->lookup, lookup,
	 (indexHigh + 1) * base->getNComps() * sizeof(Guchar));
  return cs;
}

GfxColorSpace *GfxIndexedColorSpace::parse(Array *arr) {
  GfxIndexedColorSpace *cs;
  GfxColorSpace *baseA;
  int indexHighA;
  Object obj1;
  int x;
  char *s;
  int n, i, j;

  if (arr->getLength() != 4) {
    error(-1, "Bad Indexed color space");
    goto err1;
  }
  arr->get(1, &obj1);
  if (!(baseA = GfxColorSpace::parse(&obj1))) {
    error(-1, "Bad Indexed color space (base color space)");
    goto err2;
  }
  obj1.free();
  if (!arr->get(2, &obj1)->isInt()) {
    error(-1, "Bad Indexed color space (hival)");
    delete baseA;
    goto err2;
  }
  indexHighA = obj1.getInt();
  if (indexHighA < 0 || indexHighA > 255) {
    // the PDF spec requires indexHigh to be in [0,255] -- allowing
    // values larger than 255 creates a security hole: if nComps *
    // indexHigh is greater than 2^31, the loop below may overwrite
    // past the end of the array
    error(-1, "Bad Indexed color space (invalid indexHigh value)");
    delete baseA;
    goto err2;
  }
  obj1.free();
  cs = new GfxIndexedColorSpace(baseA, indexHighA);
  arr->get(3, &obj1);
  n = baseA->getNComps();
  if (obj1.isStream()) {
    obj1.streamReset();
    for (i = 0; i <= indexHighA; ++i) {
      for (j = 0; j < n; ++j) {
	if ((x = obj1.streamGetChar()) == EOF) {
	  error(-1, "Bad Indexed color space (lookup table stream too short)");
	  goto err3;
	}
	cs->lookup[i*n + j] = (Guchar)x;
      }
    }
    obj1.streamClose();