combine {adimpro}

Pixelwise operations on a pair of images

Description

The function allows to perform pixelwise operations, specified by a supplied function, on a pair of images.

Usage

combine(img1, img2, fun = "+", rescale = TRUE, compress = TRUE, gammatype = "None",
        whitep = "D65", cspace = "Adobe", xmode = "RGB", ...)

Arguments

img1

image, object of class adimpro

img2

image, object of class adimpro, need to have the same dimension as img1

fun

A function or primitive of two (or more) arguments specifying the operation. The first argument corresponds to grey/color-values in img1, the second to img2. Auxiliary parameters can passed throug "..."

rescale

logical: if TRUE the resulting image is rescaled to fit into the range of possible grey/color-values, if FALSE values outside the range are truncated.

compress

logical, determines if image data are stored in raw-format.

gammatype

character, determines the type of gamma correction within the image. "ITU" stands for ITU-R BT.709-3 as e.g. used by dcraw. Alternatives recognized within the package are "None", "sRGB" and "CIE" (CIE L*). Please specify if you know that your image is not gamma corrected using ITU-R BT.709-3.

whitep

White point in xyY space. Can be given as one of (character) c("A","B","C","E","D50","D55","D65","D75","F2","F7","F11") or as a two element numeric vector of chromatic xy coordinates. "D65" corresponds to the default white point of "sRGB" and "Adobe" RGB-spaces.

cspace

defines the output color space, default "sRGB" (sRGB D65), alternatives are "RAW" (Camera specific), "Adobe" (Adobe 1998 D65), "wGamut" (Wide Gamut D65), "kodak" (Kodak ProPhoto D65) and "XYZ", see manpages of dcraw.

xmode

xmode determines how to interpret the values in x if length(dim(x))==3. Implemented are xmode="RGB" (default) and xmode="HSI"

...

additional parameters for function fun

Details

There are two mayor applications for this function. First it allows to add noise to an image by first creating an image that contains the noise and then adding this image using fun="+". Second it offers a way to replace parts of an image, see examples.

Value

object of class "adimpro" containing the image. The object has the following components:

img

array containing the color values in the color space specified by value$type.

type

the color space.

depth

color depth, here "16bit".

dim

vector of length 2 containing the number of pixel in horizontal and vertival direction.

file

the argument file identifying the image.

cspace

the type of rgb space used, as specified by cspace.

interp

interpolation applied by dcraw, as specified by interp.

gamma

has a gamma correction been applied, here FALSE for read.raw and TRUE for read.image

gammatype

type of gamma correction read.image.

wb

type of white balance, as specified by wb.

compressed

image data are stored as raw-vector (TRUE) or array of integers (FALSE).

Author(s)

Karsten Tabelow [e-mail] and Joerg Polzehl [e-mail]

See Also

make.image

Examples

## Not run: demo(combine)