javax.media.jai
Class IHSColorSpace

java.lang.Object
  java.awt.color.ColorSpace
      javax.media.jai.ColorSpaceJAI
          javax.media.jai.IHSColorSpace

All Implemented Interfaces:

Serializable

public final class IHSColorSpace

extends ColorSpaceJAI

Singleton class representing the IHS (Intensity, Hue, Saturation) color space (also known as HSI or HIS).

The RGB-to-IHS transformation is defined by the equations:

• I = (R+G+B)/3
• S = 1-min(R, G, B)/I
• H = G > B ? h : 2*PI - h, where
  h = cos^-1{[(R-G)+(R-B)]/2[(R-G)²+ (R-G)(G-B)]^1/2}

where the R, G, B values have been normalized to the range [0.0, 1.0]. Refer to Practical Algorithms for Image Analysis, Seul, et. al., (Cambridge, 2000), pages 50-55, for more information. The inverse transformation (IHS-to-RGB) is defined as:

When H is in [2PI/3, 4PI/3], R should be the smallest. Then, there exists

R = (1-S)I

and

• G = (c1 + c2)/2
• B = (c1 - c2)/2

where c1 = 3I-R and c2 = sqrt(3)(R-I)tg(H)

when H is in [4PI/3, 2PI],

G = (1-S)I

and

• B = (c1 + c2)/2
• R = (c1 - c2)/2

where c1 = 3I-G and c2 = sqrt(3)(G-I)tg(H-2PI/3)

when H is in [0, 2PI/3],

B = (1-S)I

and

• R = (c1 + c2)/2
• G = (c1 - c2)/2

where c1 = 3I-B and c2 = sqrt(3)(B-I)tg(H-4PI/3)

Methods defined in the superclasses are not commented extensively.

Since:

JAI 1.1

See Also:

ColorSpaceJAI, 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

protected

IHSColorSpace() Constructs an instance of this class with type ColorSpace.TYPE_HSV, 3 components, and preferred intermediary space sRGB.

Method Summary

float[]	fromCIEXYZ(float[] colorValue) Converts a single color value from CIEXYZ to IHS.
WritableRaster	fromCIEXYZ(Raster src, int[] srcComponentSize, WritableRaster dest, int[] destComponentSize) Converts a Raster of colors represented as pixels from CIEXYZ to IHS.
float[]	fromRGB(float[] rgbValue) Converts a single color value from sRGB to IHS.
WritableRaster	fromRGB(Raster src, int[] srcComponentSize, WritableRaster dest, int[] destComponentSize) Converts a Raster of colors represented as pixels from sRGB to IHS.
static IHSColorSpace	getInstance() Retrieves the unique instance of this class the construction of which is deferred until the first invocation of this method.
float[]	toCIEXYZ(float[] colorValue) Converts a single color value from IHS to CIEXYZ.
WritableRaster	toCIEXYZ(Raster src, int[] srcComponentSize, WritableRaster dest, int[] destComponentSize) Converts a Raster of colors represented as pixels from IHS to CIEXYZ.
float[]	toRGB(float[] colorValue) Converts a single color value from IHS to sRGB.
WritableRaster	toRGB(Raster src, int[] srcComponentSize, WritableRaster dest, int[] destComponentSize) Converts a Raster of colors represented as pixels from IHS to sRGB.

Methods inherited from class javax.media.jai.ColorSpaceJAI

checkParameters, CIEXYZToRGB, isRGBPreferredIntermediary, RGBToCIEXYZ

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 Detail

IHSColorSpace

protected IHSColorSpace()

Constructs an instance of this class with type ColorSpace.TYPE_HSV, 3 components, and preferred intermediary space sRGB.

Method Detail

getInstance

public static IHSColorSpace getInstance()

Retrieves the unique instance of this class the construction of which is deferred until the first invocation of this method.

fromCIEXYZ

public float[] fromCIEXYZ(float[] colorValue)

Converts a single color value from CIEXYZ to IHS.

fromRGB

public float[] fromRGB(float[] rgbValue)

Converts a single color value from sRGB to IHS.

toCIEXYZ

public float[] toCIEXYZ(float[] colorValue)

Converts a single color value from IHS to CIEXYZ.

toRGB

public float[] toRGB(float[] colorValue)

Converts a single color value from IHS to sRGB.

fromCIEXYZ

public WritableRaster fromCIEXYZ(Raster src,
                                 int[] srcComponentSize,
                                 WritableRaster dest,
                                 int[] destComponentSize)

Converts a Raster of colors represented as pixels from CIEXYZ to IHS.

Specified by:

fromCIEXYZ in class ColorSpaceJAI

Parameters:

src - the source Raster to be converted.

srcComponentSize - array that specifies the number of significant bits per source color component; ignored for floating point data. If null defaults to the value returned by src.getSampleModel().getSampleSize().

dest - the destination WritableRaster, or null.

destComponentSize - array that specifies the number of significant bits per destination color component; ignored for floating point data. If null, defaults to the value returned by dest.getSampleModel().getSampleSize(), or the sample size of the newly created destination WritableRaster if dest is null.

Returns:

dest color converted from src or a new, WritableRaster containing the converted pixels if dest is null.

fromRGB

public WritableRaster fromRGB(Raster src,
                              int[] srcComponentSize,
                              WritableRaster dest,
                              int[] destComponentSize)

Converts a Raster of colors represented as pixels from sRGB to IHS.

Specified by:

fromRGB in class ColorSpaceJAI

Parameters:

src - the source Raster to be converted.

srcComponentSize - array that specifies the number of significant bits per source color component; ignored for floating point data. If null defaults to the value returned by src.getSampleModel().getSampleSize().

dest - the destination WritableRaster, or null.

destComponentSize - array that specifies the number of significant bits per destination color component; ignored for floating point data. If null, defaults to the value returned by dest.getSampleModel().getSampleSize(), or the sample size of the newly created destination WritableRaster if dest is null.

Returns:

dest color converted from src or a new, WritableRaster containing the converted pixels if dest is null.

toCIEXYZ

public WritableRaster toCIEXYZ(Raster src,
                               int[] srcComponentSize,
                               WritableRaster dest,
                               int[] destComponentSize)

Converts a Raster of colors represented as pixels from IHS to CIEXYZ.

Specified by:

toCIEXYZ in class ColorSpaceJAI

Parameters:

src - the source Raster to be converted.

srcComponentSize - array that specifies the number of significant bits per source color component; ignored for floating point data. If null defaults to the value returned by src.getSampleModel().getSampleSize().

dest - the destination WritableRaster, or null.

destComponentSize - array that specifies the number of significant bits per destination color component; ignored for floating point data. If null, defaults to the value returned by dest.getSampleModel().getSampleSize(), or the sample size of the newly created destination WritableRaster if dest is null.

Returns:

dest color converted from src or a new, WritableRaster containing the converted pixels if dest is null.

toRGB

public WritableRaster toRGB(Raster src,
                            int[] srcComponentSize,
                            WritableRaster dest,
                            int[] destComponentSize)

Converts a Raster of colors represented as pixels from IHS to sRGB.

Specified by:

toRGB in class ColorSpaceJAI

Parameters:

src - the source Raster to be converted.

srcComponentSize - array that specifies the number of significant bits per source color component; ignored for floating point data. If null defaults to the value returned by src.getSampleModel().getSampleSize().

dest - the destination WritableRaster, or null.

destComponentSize - array that specifies the number of significant bits per destination color component; ignored for floating point data. If null, defaults to the value returned by dest.getSampleModel().getSampleSize(), or the sample size of the newly created destination WritableRaster if dest is null.

Returns:

dest color converted from src or a new, WritableRaster containing the converted pixels if dest is null.