org.faceless.pdf2
Class CMYKColorSpace

java.lang.Object
  extended by java.awt.color.ColorSpace
      extended by org.faceless.pdf2.CMYKColorSpace
All Implemented Interfaces:
Serializable

public final class CMYKColorSpace
extends ColorSpace

A subclass of ColorSpace representing the uncalibrated (device-dependent) CMYK color space available in PDF documents.

If colors need to be specified in CMYK, but device-independent color (the kind available with an ICC Profile) is not required, this ColorSpace should be used, as it doesn't require an ICC profile to be embedded in the PDF (resulting in a much smaller file). For some subsets of PDF (specifically PDF/X), RGB colors are not allowed, so anyone creating documents for that profile will probably make heavy use of this colorspace.

Typically this class will be used as follows:

 Color cyan = CMYKColorSpace.getColor(1,0,0,0);
 

Conversion to RGB

When rendering PDFs containing CMYK images or graphics to RGB, the characteristics of this space become important. Since version 2.11.8 the device-dependent space defaults to a fast generic CMYK profile, however this can be changed by setting the System property org.faceless.pdf2.DeviceCMYK to one of the following options:
genericA generic CMYK profile
swopA fast approximation of US Web Coated (SWOP) v2
fograA fast approximation of Coated FOGRA39 from ISO12647-2:2004
photoA high-contrast CMYK profile of the type used to print photos
adobeConversion to RGB is done using the algorithm from the PDF specification. This generally gives oversaturated, poor results.
ghostscriptConversion to RGB is done using the algorithm used by GhostScript. This gives results only slightly better than the Adobe algorithm.
So for example, to convert the Altona Visual Test Suite PDF to RGB using US Web Coated SWOP as the default CMYK Color profile, you could run our PDFToImage example as follows:
 java -Dorg.faceless.pdf2.DeviceCMYK=swop --model rgb PDFToImage altona_visual_1v2a_x3.pdf
 

Since:
1.1.5

Field Summary
static Color BLACK
          A convenient constant that represents the color black in the uncalibrated CMYK colorspace
static ColorSpace GRAYSPACE
           
static Color WHITE
          A convenient constant that represents the color white in the uncalibrated CMYK colorspace
 
Fields inherited from class java.awt.color.ColorSpace
CS_CIEXYZ, CS_GRAY, CS_LINEAR_RGB, CS_PYCC, CS_sRGB, TYPE_2CLR, TYPE_3CLR, TYPE_4CLR, TYPE_5CLR, TYPE_6CLR, TYPE_7CLR, TYPE_8CLR, TYPE_9CLR, TYPE_ACLR, TYPE_BCLR, TYPE_CCLR, TYPE_CMY, TYPE_CMYK, TYPE_DCLR, TYPE_ECLR, TYPE_FCLR, TYPE_GRAY, TYPE_HLS, TYPE_HSV, TYPE_Lab, TYPE_Luv, TYPE_RGB, TYPE_XYZ, TYPE_YCbCr, TYPE_Yxy
 
Method Summary
 float[] fromCIEXYZ(float[] xyz)
           
 float[] fromRGB(float[] rgb)
           
static Color getColor(float c, float m, float y, float k)
          A convenience method, returning an opaque color in the CMYK colorspace with the specified levels of cyan, magenta, yellow and black.
static Color getColor(float c, float m, float y, float k, float a)
          A convenience method, returning a color in the CMYK colorspace with the specified levels of cyan, magenta, yellow and black, and the specified alpha value.
static double getDeltaE(ColorSpace c1, ColorSpace c2)
          Return a number representing the difference between 2 ColorSpaces.
static CMYKColorSpace getInstance()
          Return a CMYK Color Space
static CMYKColorSpace getInstance(String type)
           
 float[] toCIEXYZ(float[] cmyk)
           
 float[] toRGB(float[] cmyk)
           
 int[] toRGB(int[] cmyk, int[] rgb)
           
 
Methods inherited from class java.awt.color.ColorSpace
getInstance, getMaxValue, getMinValue, getName, getNumComponents, getType, isCS_sRGB
 
Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Field Detail

BLACK

public static final Color BLACK
A convenient constant that represents the color black in the uncalibrated CMYK colorspace


WHITE

public static final Color WHITE
A convenient constant that represents the color white in the uncalibrated CMYK colorspace


GRAYSPACE

public static final ColorSpace GRAYSPACE
Method Detail

getInstance

public static CMYKColorSpace getInstance(String type)

getInstance

public static CMYKColorSpace getInstance()
Return a CMYK Color Space


toRGB

public float[] toRGB(float[] cmyk)
Specified by:
toRGB in class ColorSpace

toRGB

public int[] toRGB(int[] cmyk,
                   int[] rgb)

fromRGB

public float[] fromRGB(float[] rgb)
Specified by:
fromRGB in class ColorSpace

fromCIEXYZ

public float[] fromCIEXYZ(float[] xyz)
Specified by:
fromCIEXYZ in class ColorSpace

toCIEXYZ

public float[] toCIEXYZ(float[] cmyk)
Specified by:
toCIEXYZ in class ColorSpace

getColor

public static Color getColor(float c,
                             float m,
                             float y,
                             float k)
A convenience method, returning an opaque color in the CMYK colorspace with the specified levels of cyan, magenta, yellow and black. The parameters must be in the range from 0.0 to 1.0, or an IllegalArgumentException is thrown

Parameters:
c - the level of cyan from 0.0 to 1.0
m - the level of magenta from 0.0 to 1.0
y - the level of yellow from 0.0 to 1.0
k - the level of black from 0.0 to 1.0
Throws:
IllegalArgumentException - if any of the parameters are outside the renage 0 <= n <= 1

getColor

public static Color getColor(float c,
                             float m,
                             float y,
                             float k,
                             float a)
A convenience method, returning a color in the CMYK colorspace with the specified levels of cyan, magenta, yellow and black, and the specified alpha value. All the parameters must be in the range from 0.0 to 1.0, or an IllegalArgumentException is thrown

Parameters:
c - the level of cyan from 0.0 to 1.0
m - the level of magenta from 0.0 to 1.0
y - the level of yellow from 0.0 to 1.0
k - the level of black from 0.0 to 1.0
a - the alpha level to use - 0 is transparent, 1 is opaque.
Throws:
IllegalArgumentException - if any of the parameters are outside the renage 0 <= n <= 1

getDeltaE

public static double getDeltaE(ColorSpace c1,
                               ColorSpace c2)
Return a number representing the difference between 2 ColorSpaces. Used internally by the PDF library



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