image,Image-method {EBImage}R Documentation

Generic methods for objects of class Image

Description

Image supports all (or almost all) operations that are defined for array. However, the default behavior of some generics was redefined in the package to better suit the class. Those are:

Generic methods

show(object)
Prints a summary of image and properties (as described in 'Accessor methods' section). Prints also an excerpt of data keeping it to the minimum just to have a visual control over the atomic data type. UseimageData(x) to print or assign the full dataset. If image was put through the object detection algorithm a summary of detected objects will be printed instead of data.
as.array(x)
Removed to avoid incompatibilities with R < 2.5. Use imageData instead.
as.matrix(x, ...)
Removed to avoid incompatibilities with R < 2.5. Use as.matrix(imageData(x)) instead.
hist(x, ...)
Slightly modyfied to better suit the assumed grayscale data range [0,1].
median(x, na.rm=FALSE)
stats:median redefinition for images (bug workaround: without it median takes forever to execute without no apparent reason)
image(x, ...)
Draws image data using graphics::image keeping image aspect ratio.
[
Redefined versions (multiple signatures) of the array subsetting operator. These return objects of class Image without dropping dimensions.
Arith
Redefined arithmetic operators acting on any combination of Image with another Image or array will return an object of class Image.
as.Image)(x, ...)
S4 method for the signature x=array. Is equivalent to Image(x) when x is array.

Other important methods that directly applicable due to inheritance from the array class, just to stress that they can and should be used:

dim(x) and dim(x) <- value
Gets and sets image dimensions.
fft(z, inverse = FALSE)
Performs the Fast Fourier Transformation on an Image.
sqrt(x) etc.
Miscellaneous mathematical functions.

Author(s)

Oleg Sklyar, osklyar@ebi.ac.uk, 2006-2007

See Also

Image, IndexedImage


[Package EBImage version 2.2.0 Index]