icc_profile.java

gcc的组建

    if (buf.getInt(0) != 0x63757276) // 'curv' type
      return null;
    int count = buf.getInt(8);
    if (count == 0)
      {
	curve = new short[1];
	curve[0] = 0x0100; // 1.00 in u8fixed8
	return curve;
      }
    if (count == 1)
      {
	curve = new short[1];
	curve[0] = buf.getShort(12); // other u8fixed8 gamma
	return curve;
      }
    curve = new short[count];
    for (int i = 0; i < count; i++)
      curve[i] = buf.getShort(12 + i * 2);
    return curve;
  }

  /**
   * Returns XYZ tristimulus values for an 'XYZ ' type tag
   * @return the XYZ values, or null if the tag was not an 'XYZ ' type tag.
   *
   * (Package private - used by ICC_ProfileXYZ and ICC_ProfileGray)
   */
  float[] getXYZData(int signature)
  {
    byte[] data = getData(signature);

    // can't find tag?
    if (data == null)
      return null;

    // not an XYZData type tag?
    ByteBuffer buf = ByteBuffer.wrap(data);
    if (buf.getInt(0) != icSigXYZData) // 'XYZ ' type
      return null;

    float[] point = new float[3];

    // get the X,Y,Z tristimulus values
    point[0] = ((float) buf.getInt(8)) / 65536f;
    point[1] = ((float) buf.getInt(12)) / 65536f;
    point[2] = ((float) buf.getInt(16)) / 65536f;
    return point;
  }

  /**
   * Returns the profile ID if it's a predefined profile
   * Or -1 for a profile loaded from an ICC profile
   *
   * (Package private - used by ICC_ColorSpace)
   */
  int isPredefined()
  {
    return profileID;
  }

  /**
   * Creates a tag of XYZ-value type.
   */
  private byte[] makeXYZData(float[] values)
  {
    ByteBuffer buf = ByteBuffer.allocate(20);
    buf.putInt(0, icSigXYZData); // 'XYZ '
    buf.putInt(4, 0);
    buf.putInt(8, (int) (values[0] * 65536.0));
    buf.putInt(12, (int) (values[1] * 65536.0));
    buf.putInt(16, (int) (values[2] * 65536.0));
    return buf.array();
  }

  /**
   * Creates a tag of text type
   */
  private byte[] makeTextTag(String text)
  {
    int length = text.length();
    ByteBuffer buf = ByteBuffer.allocate(8 + length + 1);
    byte[] data;
    try
      {
	data = text.getBytes("US-ASCII");
      }
    catch (UnsupportedEncodingException e)
      {
	data = new byte[length]; // shouldn't happen
      }

    buf.putInt(0, (int) 0x74657874); // 'text'
    buf.putInt(4, 0);
    for (int i = 0; i < length; i++)
      buf.put(8 + i, data[i]);
    buf.put(8 + length, (byte) 0); // null-terminate
    return buf.array();
  }

  /**
   * Creates a tag of textDescriptionType
   */
  private byte[] makeDescTag(String text)
  {
    int length = text.length();
    ByteBuffer buf = ByteBuffer.allocate(90 + length + 1);
    buf.putInt(0, (int) 0x64657363); // 'desc'
    buf.putInt(4, 0); // reserved 
    buf.putInt(8, length + 1); // ASCII length, including null termination
    byte[] data;

    try
      {
	data = text.getBytes("US-ASCII");
      }
    catch (UnsupportedEncodingException e)
      {
	data = new byte[length]; // shouldn't happen
      }

    for (int i = 0; i < length; i++)
      buf.put(12 + i, data[i]);
    buf.put(12 + length, (byte) 0); // null-terminate

    for (int i = 0; i < 39; i++)
      buf.putShort(13 + length + (i * 2), (short) 0); // 78 bytes we can ignore

    return buf.array();
  }

  /**
   * Creates a tag of TRC type (linear curve)
   */
  private byte[] makeTRC()
  {
    ByteBuffer buf = ByteBuffer.allocate(12);
    buf.putInt(0, 0x63757276); // 'curv' type
    buf.putInt(4, 0); // reserved
    buf.putInt(8, 0);
    return buf.array();
  }

  /**
   * Creates a tag of TRC type (single gamma value)
   */
  private byte[] makeTRC(float gamma)
  {
    short gammaValue = (short) (gamma * 256f);
    ByteBuffer buf = ByteBuffer.allocate(14);
    buf.putInt(0, 0x63757276); // 'curv' type
    buf.putInt(4, 0); // reserved
    buf.putInt(8, 1);
    buf.putShort(12, gammaValue); // 1.00 in u8fixed8
    return buf.array();
  }

  /**
   * Creates a tag of TRC type (TRC curve points)
   */
  private byte[] makeTRC(float[] trc)
  {
    ByteBuffer buf = ByteBuffer.allocate(12 + 2 * trc.length);
    buf.putInt(0, 0x63757276); // 'curv' type
    buf.putInt(4, 0); // reserved
    buf.putInt(8, trc.length); // number of points

    // put the curve values 
    for (int i = 0; i < trc.length; i++)
      buf.putShort(12 + i * 2, (short) (trc[i] * 65535f));

    return buf.array();
  }

  /**
   * Creates an identity color lookup table.
   */
  private byte[] makeIdentityClut()
  {
    final int nIn = 3;
    final int nOut = 3;
    final int nInEntries = 256;
    final int nOutEntries = 256;
    final int gridpoints = 16;

    // gridpoints**nIn
    final int clutSize = 2 * nOut * gridpoints * gridpoints * gridpoints;
    final int totalSize = clutSize + 2 * nInEntries * nIn
                          + 2 * nOutEntries * nOut + 52;

    ByteBuffer buf = ByteBuffer.allocate(totalSize);
    buf.putInt(0, 0x6D667432); // 'mft2'
    buf.putInt(4, 0); // reserved
    buf.put(8, (byte) nIn); // number input channels
    buf.put(9, (byte) nOut); // number output channels
    buf.put(10, (byte) gridpoints); // number gridpoints
    buf.put(11, (byte) 0); // padding

    // identity matrix
    buf.putInt(12, 65536); // = 1 in s15.16 fixed point
    buf.putInt(16, 0);
    buf.putInt(20, 0);
    buf.putInt(24, 0);
    buf.putInt(28, 65536);
    buf.putInt(32, 0);
    buf.putInt(36, 0);
    buf.putInt(40, 0);
    buf.putInt(44, 65536);

    buf.putShort(48, (short) nInEntries); // input table entries
    buf.putShort(50, (short) nOutEntries); // output table entries

    // write the linear input channels, unsigned 16.16 fixed point,
    // from 0.0 to FF.FF
    for (int channel = 0; channel < 3; channel++)
      for (int i = 0; i < nInEntries; i++)
        {
	  short n = (short) ((i << 8) | i); // assumes 256 entries
	  buf.putShort(52 + (channel * nInEntries + i) * 2, n);
        }
    int clutOffset = 52 + nInEntries * nIn * 2;

    for (int x = 0; x < gridpoints; x++)
      for (int y = 0; y < gridpoints; y++)
	for (int z = 0; z < gridpoints; z++)
	  {
	    int offset = clutOffset + z * 2 * nOut + y * gridpoints * 2 * nOut
	                 + x * gridpoints * gridpoints * 2 * nOut;
	    double xf = ((double) x) / ((double) gridpoints - 1.0);
	    double yf = ((double) y) / ((double) gridpoints - 1.0);
	    double zf = ((double) z) / ((double) gridpoints - 1.0);
	    buf.putShort(offset, (short) (xf * 65535.0));
	    buf.putShort(offset + 2, (short) (yf * 65535.0));
	    buf.putShort(offset + 4, (short) (zf * 65535.0));
	  }

    for (int channel = 0; channel < 3; channel++)
      for (int i = 0; i < nOutEntries; i++)
        {
	  short n = (short) ((i << 8) | i); // assumes 256 entries
	  buf.putShort(clutOffset + clutSize + (channel * nOutEntries + i) * 2,
	               n);
        }

    return buf.array();
  }

  /**
   * Creates profile data corresponding to the built-in colorspaces.
   */
  private void createProfile(int colorSpace) throws IllegalArgumentException
  {
    this.profileID = colorSpace;
    header = new ProfileHeader();
    tagTable = new Hashtable();

    switch (colorSpace)
      {
      case ColorSpace.CS_sRGB:
	createRGBProfile();
	return;
      case ColorSpace.CS_LINEAR_RGB:
	createLinearRGBProfile();
	return;
      case ColorSpace.CS_CIEXYZ:
	createCIEProfile();
	return;
      case ColorSpace.CS_GRAY:
	createGrayProfile();
	return;
      case ColorSpace.CS_PYCC:
	createPyccProfile();
	return;
      default:
	throw new IllegalArgumentException("Not a predefined color space!");
      }
  }

  /**
   * Creates an ICC_Profile representing the sRGB color space
   */
  private void createRGBProfile()
  {
    header.setColorSpace( ColorSpace.TYPE_RGB );
    header.setProfileColorSpace( ColorSpace.TYPE_XYZ );
    ICC_ColorSpace cs = new ICC_ColorSpace(this);

    float[] r = { 1f, 0f, 0f };
    float[] g = { 0f, 1f, 0f };
    float[] b = { 0f, 0f, 1f };
    float[] black = { 0f, 0f, 0f };

    // CIE 1931 D50 white point (in Lab coordinates)
    float[] white = D50;

    // Get tristimulus values (matrix elements)
    r = cs.toCIEXYZ(r);
    g = cs.toCIEXYZ(g);
    b = cs.toCIEXYZ(b);

    // Generate the sRGB TRC curve, this is the linear->nonlinear
    // RGB transform.
    cs = new ICC_ColorSpace(getInstance(ICC_ColorSpace.CS_LINEAR_RGB));
    float[] points = new float[TRC_POINTS];
    float[] in = new float[3];
    for (int i = 0; i < TRC_POINTS; i++)
      {
	in[0] = in[1] = in[2] = ((float) i) / ((float) TRC_POINTS - 1);
	in = cs.fromRGB(in);
	// Note this value is the same for all components.
	points[i] = in[0];
      }

    setData(icSigRedColorantTag, makeXYZData(r));
    setData(icSigGreenColorantTag, makeXYZData(g));
    setData(icSigBlueColorantTag, makeXYZData(b));
    setData(icSigMediaWhitePointTag, makeXYZData(white));
    setData(icSigMediaBlackPointTag, makeXYZData(black));
    setData(icSigRedTRCTag, makeTRC(points));
    setData(icSigGreenTRCTag, makeTRC(points));
    setData(icSigBlueTRCTag, makeTRC(points));
    setData(icSigCopyrightTag, makeTextTag(copyrightNotice));
    setData(icSigProfileDescriptionTag, makeDescTag("Generic sRGB"));
    this.profileID = ColorSpace.CS_sRGB;
  }

  /**
   * Creates an linear sRGB profile
   */
  private void createLinearRGBProfile()
  {
    header.setColorSpace(ColorSpace.TYPE_RGB);
    header.setProfileColorSpace(ColorSpace.TYPE_XYZ);
    ICC_ColorSpace cs = new ICC_ColorSpace(this);

    float[] r = { 1f, 0f, 0f };
    float[] g = { 0f, 1f, 0f };
    float[] b = { 0f, 0f, 1f };
    float[] black = { 0f, 0f, 0f };

    float[] white = D50;

    // Get tristimulus values (matrix elements)
    r = cs.toCIEXYZ(r);
    g = cs.toCIEXYZ(g);
    b = cs.toCIEXYZ(b);

    setData(icSigRedColorantTag, makeXYZData(r));
    setData(icSigGreenColorantTag, makeXYZData(g));
    setData(icSigBlueColorantTag, makeXYZData(b));

    setData(icSigMediaWhitePointTag, makeXYZData(white));
    setData(icSigMediaBlackPointTag, makeXYZData(black));

    setData(icSigRedTRCTag, makeTRC());
    setData(icSigGreenTRCTag, makeTRC());
    setData(icSigBlueTRCTag, makeTRC());
    setData(icSigCopyrightTag, makeTextTag(copyrightNotice));
    setData(icSigProfileDescriptionTag, makeDescTag("Linear RGB"));
    this.profileID = ColorSpace.CS_LINEAR_RGB;
  }

  /**
   * Creates an CIE XYZ identity profile
   */
  private void createCIEProfile()
  {
    header.setColorSpace( ColorSpace.TYPE_XYZ );
    header.setProfileColorSpace( ColorSpace.TYPE_XYZ );
    header.setProfileClass( CLASS_COLORSPACECONVERSION );
    ICC_ColorSpace cs = new ICC_ColorSpace(this);

    float[] white = D50;

    setData(icSigMediaWhitePointTag, makeXYZData(white));
    setData(icSigAToB0Tag, makeIdentityClut());
    setData(icSigBToA0Tag, makeIdentityClut());
    setData(icSigCopyrightTag, makeTextTag(copyrightNotice));
    setData(icSigProfileDescriptionTag, makeDescTag("CIE XYZ identity profile"));
    this.profileID = ColorSpace.CS_CIEXYZ;
  }

  /**
   * Creates a linear gray ICC_Profile
   */
  private void createGrayProfile()
  {
    header.setColorSpace(ColorSpace.TYPE_GRAY);
    header.setProfileColorSpace(ColorSpace.TYPE_XYZ);

    // CIE 1931 D50 white point (in Lab coordinates)
    float[] white = D50;

    setData(icSigMediaWhitePointTag, makeXYZData(white));
    setData(icSigGrayTRCTag, makeTRC(1.0f));
    setData(icSigCopyrightTag, makeTextTag(copyrightNotice));
    setData(icSigProfileDescriptionTag, makeDescTag("Linear grayscale"));
    this.profileID = ColorSpace.CS_GRAY;
  }

  /**
   * XXX Implement me
   */
  private void createPyccProfile()
  {
    header.setColorSpace(ColorSpace.TYPE_3CLR);
    header.setProfileColorSpace(ColorSpace.TYPE_XYZ);

    // Create CLUTs here. :-)

    setData(icSigCopyrightTag, makeTextTag(copyrightNotice));
    setData(icSigProfileDescriptionTag, makeDescTag("Photo YCC"));
    this.profileID = ColorSpace.CS_PYCC;
  }
} // class ICC_Profile