Package org.loboevolution.pdfview.colorspace

Class CMYKColorSpace

java.lang.Object

java.awt.color.ColorSpace

org.loboevolution.pdfview.colorspace.CMYKColorSpace

All Implemented Interfaces:

Serializable

public class CMYKColorSpace
extends ColorSpace

A ColorSpace for the CMYK color space.

Take from net.sf.jcgm.core.CMYKColorSpace.java

Author XOND

Version:

$Id: CMYKColorSpace.java,v 1.2 2011-01-06 12:12:21 xond Exp $

See Also:

• Serialized Form

Field Summary

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

Constructor Summary

Constructors

Constructor	Description
CMYKColorSpace()	Create a new CMYKColorSpace Instance.

Method Summary

Modifier and Type	Method	Description
float[]	fromCIEXYZ(float[] p_colorvalue)
float[]	fromRGB(float[] p_rgbvalue)
float[]	normalize(float[] p_colors)	Normalize ensures all color values returned are between 0 and 1.
float[]	toCIEXYZ(float[] p_colorvalue)
float[]	toRGB(float[] p_colorvalue)

Methods inherited from class java.awt.color.ColorSpace

getInstance, getMaxValue, getMinValue, getName, getNumComponents, getType, isCS_sRGB

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

CMYKColorSpace

public CMYKColorSpace()

Create a new CMYKColorSpace Instance.

Method Details

fromCIEXYZ

public float[] fromCIEXYZ(float[] p_colorvalue)

Converts to CMYK from CIEXYZ. We cheat here, using the RGB colorspace to do the math for us. The toCIEXYZ function has a description of how this is supposed to work, which may be implemented in the future.

Specified by:

fromCIEXYZ in class ColorSpace

See Also:

• ColorSpace.fromCIEXYZ(float[])

fromRGB

public float[] fromRGB(float[] p_rgbvalue)

Converts a given RGB to CMYK. RGB doesn't really use black, so K will always be 0. On printers, the black should actually look dark brown. RGB (an additive space) is simply the backwards from CMY (a subtractive space), so all we do is:

C = 1-R M = 1-G Y = 1-B

Specified by:

fromRGB in class ColorSpace

See Also:

• ColorSpace.fromRGB(float[])

toCIEXYZ

public float[] toCIEXYZ(float[] p_colorvalue)

Converts the CMYK color to CIEXYZ. Because CIEXYZ is 3-component, we cheat, converting to RGB and then using the RGB colorspace function to do the conversion. Details on this colorspace are available on wikipedia:

...

There is also an "ideal relationship" to CMYK, which might be implemented in the future (don't recall the reference we got this from, probably color.org):

C = (C' - K)/(1 - K) M = (M' - K)/(1 - K) Y = (Y' - K)/(1 - K) K = Min(C', M', Y')

X 41.2453 35.7580 18.0423 | 1-C' Y = 21.2671 71.5160 07.2169 | 1-M' Z 01.9334 11.9193 95.0227 | 1-Y'

Specified by:

toCIEXYZ in class ColorSpace

See Also:

• ColorSpace.toCIEXYZ(float[])

toRGB

public float[] toRGB(float[] p_colorvalue)

Converts CMYK colors to RGB. Note that converting back will be lossy. The formula for this is:

K = 1 - K (go to additive) R = K * (1 - C) G = K * (1 - M) B = K * (1 - Y)

Specified by:

toRGB in class ColorSpace

See Also:

• ColorSpace.toRGB(float[])

normalize

public float[] normalize(float[] p_colors)

Normalize ensures all color values returned are between 0 and 1.

Parameters:

p_colors - an array of

invalid reference

float

objects.

Returns:

p_colors, with any values greater than 1 set to 1, and less than 0 set to 0.