com.lizardtech.djvu
Class GBitmap

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

All Implemented Interfaces:

DjVuInterface, java.lang.Cloneable

public class GBitmap
extends GMap
implements java.lang.Cloneable

This class represents bitonal and gray scale pixel images.

Version:

$Revision: 1.15 $

Author:

Bill C. Riemers

Field Summary

protected int

grays Color depth

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

GBitmap()
Creates a new GBitmap object.

Method Summary

boolean	blit(GBitmap bm, int xh, int yh, int subsample) Insert another bitmap at the specified location.
GRect	compute_bounding_box() Find the bounding box for non-white pixels.
static GBitmap	createGBitmap(DjVuInterface ref) Creates an instance of GBitmap with the options interherited from the specified reference.
void	fill(GMap ref, int dx, int dy) Insert the reference map at the specified location.
void	fill(short value) Set the value of all pixels.
boolean	getBooleanAt(int offset) Query a pixel as boolean
protected int	getBorder() Query the border width.
int	getByteAt(int offset) Query the pixel at a particular location
int	getBytesPerRow() Query the number of bytes per row.
int	getGrays() Query the color depth.
GPixel[]	getRamp()
int	getRowSize() Query the number of bytes per row.
GBitmap	init(GBitmap ref) Initialize this map by copying a reference map
GBitmap	init(GBitmap ref, GRect rect, int border) /** Initialize this map by copying a reference map
GBitmap	init(GBitmap ref, int aborder) Initialize this map by copying a reference map
GBitmap	init(int arows, int acolumns, int aborder) Initialize this image with the specified values.
boolean	insertMap(GBitmap bit, int dx, int dy, boolean doBlit) Insert the reference map at the specified location.
boolean	isRampNeeded() Query if we are allowed to skip the ramp call.
GPixel	ramp(GPixelReference ref) Convert the pixel to 24 bit color.
int	rowOffset(int row) Query the start offset of a row.
void	setByteAt(int offset, int value) Set the pixel value.
void	setGrays(int ngrays) Set the color depth
void	setMinimumBorder(int minimum) Set the minimum border needed
GMap	translate(int dx, int dy, GMap retval) Shift the origin of the image by coping the pixel data.

Methods inherited from class com.lizardtech.djvu.GMap

clone, columns, createGPixelReference, createGPixelReference, fillRGBPixels, getBlueOffset, getColorSize, getData, getGreenOffset, getRedOffset, 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

grays

protected int grays

Color depth

Constructor Detail

GBitmap

public GBitmap()

Creates a new GBitmap object.

Method Detail

getRamp

public GPixel[] getRamp()

createGBitmap

public static GBitmap createGBitmap(DjVuInterface ref)

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

Parameters:

ref - Object to interherit DjVuOptions from.

Returns:

a new instance of GBitmap.

getBooleanAt

public final boolean getBooleanAt(int offset)

Query a pixel as boolean

Parameters:

offset - position to query

Returns:

true if zero

setByteAt

public final void setByteAt(int offset,
                            int value)

Set the pixel value.

Parameters:

offset - position of the pixel to set

value - gray scale value to set

getByteAt

public final int getByteAt(int offset)

Query the pixel at a particular location

Parameters:

offset - the pixel location

Returns:

the gray scale value

getBytesPerRow

public int getBytesPerRow()

Query the number of bytes per row.

Returns:

the number of bytes per row

getGrays

public final int getGrays()

Query the color depth.

Returns:

number of grays

setGrays

public void setGrays(int ngrays)

Set the color depth

Parameters:

ngrays - number of grays

Throws:

java.lang.IllegalArgumentException - if the number of grays is less than 2 or greater than 256

blit

public boolean blit(GBitmap bm,
                    int xh,
                    int yh,
                    int subsample)

Insert another bitmap at the specified location. Note that both bitmaps need to have the same number of grays.

Parameters:

bm - bitmap to insert

xh - horizontal location to insert at

yh - vertical location to insert at

subsample - rate to subsample at

Returns:

true if the blit intersected this bitmap

rowOffset

public final int rowOffset(int row)

Query the start offset of a row.

Overrides:

rowOffset in class GMap

Parameters:

row - the row to query

Returns:

the offset to the pixel data

getRowSize

public final int getRowSize()

Query the number of bytes per row.

Overrides:

getRowSize in class GMap

Returns:

bytes per row

fill

public void fill(short value)

Set the value of all pixels.

Parameters:

value - gray scale value to assign to all pixels

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

insertMap

public boolean insertMap(GBitmap bit,
                         int dx,
                         int dy,
                         boolean doBlit)

Insert the reference map at the specified location.

Parameters:

bit - map to insert

dx - horizontal position to insert at

dy - vertical position to insert at

doBlit - true if the gray scale values should be added

Returns:

true if pixels are inserted

init

public GBitmap init(int arows,
                    int acolumns,
                    int aborder)

Initialize this image with the specified values.

Parameters:

arows - number of rows

acolumns - number of columns

aborder - width of the border

Returns:

the initialized image map

init

public final GBitmap init(GBitmap ref)

Initialize this map by copying a reference map

Parameters:

ref - map to copy

Returns:

the initialized map

init

public GBitmap init(GBitmap ref,
                    int aborder)

Initialize this map by copying a reference map

Parameters:

ref - map to copy

aborder - number of border pixels

Returns:

the initialized map

init

public GBitmap init(GBitmap ref,
                    GRect rect,
                    int border)

/** Initialize this map by copying a reference map

Parameters:

ref - map to copy

rect - area to copy

border - number of border pixels

Returns:

the initialized map

setMinimumBorder

public void setMinimumBorder(int minimum)

Set the minimum border needed

Parameters:

minimum - the minumum border needed

translate

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

Shift the origin of the image by coping the pixel data.

Specified by:

translate in class GMap

Parameters:

dx - amount to shift the origin of the x-axis

dy - amount to shift the origin of the y-axis

retval - the image to copy the data into

Returns:

the translated image

getBorder

protected final int getBorder()

Query the border width.

Returns:

the border width

ramp

public GPixel ramp(GPixelReference ref)

Convert the pixel to 24 bit color.

Overrides:

ramp in class GMap

Returns:

the converted pixel

isRampNeeded

public boolean isRampNeeded()

Query if we are allowed to skip the ramp call.

Overrides:

isRampNeeded in class GMap

Returns:

true if not 24 bit color

compute_bounding_box

public GRect compute_bounding_box()

Find the bounding box for non-white pixels.

Returns:

bounding rectangle