lejos.hardware.lcd

Class Image

java.lang.Object

lejos.hardware.lcd.Image

All Implemented Interfaces:

java.io.Serializable

public class Image
extends java.lang.Object
implements java.io.Serializable

Provides support for in memory images. The format of the bitmap is in standard leJOS format (so aligned for use on EV3 LCD display). There is one bit per pixel. The pixels are packed into bytes with each byte spanning 8 scan lines. The least significant bit of each byte is the pixel for the top most scan line, the most significant bit is the 8th scan line. Values of 1 represent black. 0 white. This class implements a sub set of the standard lcdui Image class. Only mutable images are supported and the ARGB methods are not available. TODO: This file needs to be updated to match the EV3 image format.

Author:

Andre Nijholt & Andy Shaw

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
Image(int width, int height, byte[] data) Create an image using an already existing byte array.

Method Summary

Modifier and Type	Method and Description
static Image	createImage(Image image, int x, int y, int w, int h, int transform) Creates a new image based upon the transformed region of another image
static Image	createImage(java.io.InputStream s) Read image from file.
static Image	createImage(int width, int height) Create ablank image of the requested size.
byte[]	getData() Return the byte array used to hold the image data.
GraphicsLCD	getGraphics() Returns a graphics object that can be used to draw to the image.
int	getHeight() return the height of the image.
int	getWidth() Return the width of the image.

Methods inherited from class java.lang.Object

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

Constructor Detail

Image

public Image(int width,
             int height,
             byte[] data)

Create an image using an already existing byte array. The byte array is used to store the image data. The array may already be initialized with image data.
Note: This is a non standard constructor.

Parameters:

width - width of the image

height - height of the image

data - The byte array to be used for image store/

Method Detail

createImage

public static Image createImage(int width,
                                int height)

Create ablank image of the requested size.

Parameters:

width -

height -

Returns:

Returns the new image.

createImage

public static Image createImage(java.io.InputStream s)
                         throws java.io.IOException

Read image from file. An image file has the following format:

1st byte - 4th byte	5th byte - 8th byte	9th byte	10th byte ....
image-width (int)	image-height (int)	0x00(image data delimit)	byte image data....

For example:

After a file with content

width (int)	height (int)	delimit	byte data
00 00 00 03	00 00 00 05	00	00	02	1f

was read, this method will return an object which is equivalent to

new Image(3, 5, new byte[] {(byte)0x00, (byte)0x02, (byte)0x1f})

Parameters:

s - The input stream for the image file.

Returns:

an ev3 image object.

Throws:

java.io.IOException - if an input or output error occurs or file format is not correct.

See Also:

Image, Image(int, int, byte[])

createImage

public static Image createImage(Image image,
                                int x,
                                int y,
                                int w,
                                int h,
                                int transform)

Creates a new image based upon the transformed region of another image

Parameters:

image - Source image

x - x co-ordinate of the source region

y - y co-ordinate of the source region

w - width of the source region

h - height of the source region

transform - Transform to be applied

Returns:

New image

getWidth

public int getWidth()

Return the width of the image.

Returns:

Image width

getHeight

public int getHeight()

return the height of the image.

Returns:

image height

getData

public byte[] getData()

Return the byte array used to hold the image data.
Note: This is a non standard method.

Returns:

The image byte array.

getGraphics

public GraphicsLCD getGraphics()

Returns a graphics object that can be used to draw to the image.

Returns:

graphics object.

See Also:

GraphicsLCD