com.lizardtech.djvu
Class GPixmap

java.lang.Object
  com.lizardtech.djvu.DjVuObject
      com.lizardtech.djvu.GMap
          com.lizardtech.djvu.GPixmap

All Implemented Interfaces:

DjVuInterface, java.lang.Cloneable

public class GPixmap
extends GMap
implements java.lang.Cloneable

This class represents 24 bit color image maps.

Version:

$ $

Author:

Bill C. Riemers

Field Summary

protected static byte[]	clip Used to quickly clip out of bounds values.
protected static int[]	ctable Cached color correction table.
protected static int[]	ctableI Indentity color correction table.
protected static int[]	invmap Used to represent division as multiplication.
protected static double	lgamma The color correction subsample for the cached color table.
protected static java.lang.Object[]	multiplierRefArray Used for attenuation

Fields inherited from class com.lizardtech.djvu.GMap

blueOffset, data, greenOffset, ncolors, ncolumns, needRamp, nrows, properties, redOffset

Fields inherited from class com.lizardtech.djvu.DjVuObject

hasReferences

Constructor Summary

GPixmap()
Creates a new GPixmap object.

Method Summary

void	applyGammaCorrection(double gamma) Correct the colors with a gamma subsample normalized to 1.0 for no correction.
void	attenuate(GBitmap bm, int xpos, int ypos) Attenuate the specified bitmap.
void	blit(GBitmap bm, int xpos, int ypos, GPixel color) Insert the specified bitmap with the specified color.
static GPixmap	createGPixmap(DjVuInterface ref) Creates an instance of GPixmap with the options interherited from the specified reference.
void	downsample(GMap src, int subsample, GRect pdr) Fill this image from another source at reduced resolution.
void	downsample43(GMap src, GRect pdr) Fill this image from another source at reduced resolution of 4 vertical pixels to 3.
void	fill(GMap ref, int dx, int dy) Insert the reference map at the specified location.
static int[]	getColorCorrection(double gamma) Fill the array with color correction constants.
protected static int[]	getMultiplier(int maxgray) Creates or retrieves a cached multiplier array to use when attenuating.
GPixmap	init(GMap ref) Initialize this pixmap from another image map.
GPixmap	init(GMap ref, GRect rect) Initialize this pixmap from a segment of another image map.
GPixmap	init(int arows, int acolumns, GPixel filler) Initialize this pixmap to the specified size and fill in the specified color.
void	stencil(GBitmap mask, GPixmap foregroundMap, int supersample, int subsample, GRect bounds, double gamma) Draw the foreground layer onto this background image.
GMap	translate(int dx, int dy, GMap retval) Copy this image with a translated origin.

Methods inherited from class com.lizardtech.djvu.GMap

clone, columns, createGPixelReference, createGPixelReference, fillRGBPixels, getBlueOffset, getColorSize, getData, getGreenOffset, getRedOffset, getRowSize, isRampNeeded, ramp, rowOffset, rows

Methods inherited from class com.lizardtech.djvu.DjVuObject

checkLockTime, create, create, createSoftReference, createWeakReference, getDjVuOptions, getFromReference, invoke, setDjVuOptions

Methods inherited from class java.lang.Object

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

Field Detail

invmap

protected static final int[] invmap

Used to represent division as multiplication.

ctableI

protected static final int[] ctableI

Indentity color correction table.

ctable

protected static int[] ctable

Cached color correction table.

lgamma

protected static double lgamma

The color correction subsample for the cached color table.

clip

protected static final byte[] clip

Used to quickly clip out of bounds values.

multiplierRefArray

protected static final java.lang.Object[] multiplierRefArray

Used for attenuation

Constructor Detail

GPixmap

public GPixmap()

Creates a new GPixmap object.

Method Detail

createGPixmap

public static GPixmap createGPixmap(DjVuInterface ref)

Creates an instance of GPixmap with the options interherited from the specified reference.

Parameters:

ref - Object to interherit DjVuOptions from.

Returns:

a new instance of GPixmap.

getColorCorrection

public static int[] getColorCorrection(double gamma)

Fill the array with color correction constants.

Parameters:

gamma - color correction subsample

Returns:

the new color correction table

getMultiplier

protected static int[] getMultiplier(int maxgray)

Creates or retrieves a cached multiplier array to use when attenuating.

Returns:

attenuation array

attenuate

public void attenuate(GBitmap bm,
                      int xpos,
                      int ypos)

Attenuate the specified bitmap.

Parameters:

bm - Bitmap to attenuate

xpos - horizontal position

ypos - vertical position

blit

public void blit(GBitmap bm,
                 int xpos,
                 int ypos,
                 GPixel color)

Insert the specified bitmap with the specified color.

Parameters:

bm - bitmap to insert

xpos - horizontal position

ypos - vertical position

color - color to insert bitmap with

applyGammaCorrection

public final void applyGammaCorrection(double gamma)

Correct the colors with a gamma subsample normalized to 1.0 for no correction.

Parameters:

gamma - color correction

downsample

public void downsample(GMap src,
                       int subsample,
                       GRect pdr)

Fill this image from another source at reduced resolution. Pixel averaging will be used.

Parameters:

src - image map to reduce

subsample - rate to subsample

pdr - target bounds

downsample43

public void downsample43(GMap src,
                         GRect pdr)

Fill this image from another source at reduced resolution of 4 vertical pixels to 3. An extrapulating pixel averaging algorithm is used.

Parameters:

src - image map to reduce

pdr - target bounds

Throws:

java.lang.IllegalArgumentException - if the target rectangle is out of bounds

fill

public void fill(GMap ref,
                 int dx,
                 int dy)

Insert the reference map at the specified location.

Specified by:

fill in class GMap

Parameters:

ref - map to insert

dx - horizontal position to insert at

dy - vertical position to insert at

init

public GPixmap init(int arows,
                    int acolumns,
                    GPixel filler)

Initialize this pixmap to the specified size and fill in the specified color.

Parameters:

arows - number of rows

acolumns - number of columns

filler - fill color

Returns:

the initialized pixmap

init

public GPixmap init(GMap ref,
                    GRect rect)

Initialize this pixmap from a segment of another image map.

Parameters:

ref - image map to initialize from

rect - bounding rectangle to initialize from

Returns:

the initialized pixmap

init

public GPixmap init(GMap ref)

Initialize this pixmap from another image map.

Parameters:

ref - image map to initialize from

Returns:

the initialized pixmap

stencil

public void stencil(GBitmap mask,
                    GPixmap foregroundMap,
                    int supersample,
                    int subsample,
                    GRect bounds,
                    double gamma)

Draw the foreground layer onto this background image.

Parameters:

mask - the mask layer

foregroundMap - the foreground colors

supersample - rate to upsample the foreground colors

subsample - rate to subsample the foreground colors

bounds - the target rectangle

gamma - color correction factor

Throws:

java.lang.IllegalArgumentException - if the specified bounds are not contained in the page

translate

public GMap translate(int dx,
                      int dy,
                      GMap retval)

Copy this image with a translated origin.

Specified by:

translate in class GMap

Parameters:

dx - horizontal distance to translate

dy - vertical distance to translate

retval - an old image to try and reuse for the return value

Returns:

the translated image