The RGBImage class

Description

Package: R.image
Class RGBImage

Object
~~|
~~+--BitmapImage
~~~~~~~|
~~~~~~~+--RGBImage

Directly known subclasses:

public static class RGBImage
extends BitmapImage

The RGBImage class provides methods to read, write and display images in the RGB file format.

Usage

RGBImage(R=NULL, G=NULL, B=NULL, ndim=3)

Arguments

Fields and Methods

Fields

R	The red channel data.
G	The green channel data.
B	The blue channel data.
depth	The depth in bitlayers.

Note that R, G and B must have values in the range [0,255]. They must be matrices of the same dimension with the number of rows equal to the height of the image, and the number of columns equal to the width of the image. The elements in the first row and the first column of the matrices represents the top left pixel.

Methods:

	as.GrayImage	-
	as.MonochromeImage	Converts an RGB image to a gray scale image.
	as	-
	as.RGBImage	-
	crop	Crops the image.
	dim	-
	equals	Compares two RGBImage's.
	getColors	-
	paste	Pastes another RGBImage or image layers to this image.
	readPPM	-
	readRGB	-
	writePBM	-
	writePGM	-
	writePPM	Writes the image to a file in Portable PixMap (PPM) format.
	writeRGB	Writes the image to a file in RGB format.

Methods inherited from BitmapImage:
as.character, depth, dim, getColorMap, getColors, height, image, plot, points, read, readJPEG, readUsingExternal, width, write, writeBMP, writeEPS, writeJPG, writePBM, writePGM, writePNG, writePPM, writeRGB

Methods inherited from Object:
$, $<-, [[, [[<-, as.character, attach, attachLocally, clearCache, clone, detach, equals, extend, finalize, gc, getEnvironment, getFields, getInstanciationTime, getStaticInstance, hasField, hashCode, ll, load, objectSize, print, save

Author(s)

Henrik Bengtsson (http://www.braju.com/R/)

See Also

For converting images in of file formats see ImageMagick (http://www.imagemagick.org), which is free and available for many differt platforms.

Examples

rgb <- BitmapImage$read("logosm.ppm", path=system.file("images", package="R.image"))

layout(matrix(1:4,ncol=2))
image(rgb)
for (ch in 1:3) {
  coefs <- c(0,0,0)
  coefs[ch] <- 1
  chimg <- as.RGBImage(rgb, coefs=coefs)
  image(chimg)
}