R: Extract Pixel Centres as Point Pattern

pixelcentres {spatstat} | R Documentation

## Extract Pixel Centres as Point Pattern

### Description

Given a pixel image or binary mask window, extract the centres of all pixels and return them as a point pattern.

### Usage

    pixelcentres(X, W = NULL, ...)

### Arguments

`X` | Pixel image (object of class `"im"`) or window (object of class `"owin"`).
`W` | Optional window to contain the resulting point pattern.
`...` | Optional arguments defining the pixel resolution.

### Details

If the argument `X` is a pixel image, the result is a point pattern, consisting of the centre of every pixel whose pixel value is not `NA`.

If `X` is a window which is a binary mask, the result is a point pattern consisting of the centre of every pixel inside the window (i.e. every pixel for which the mask value is `TRUE`).

Otherwise, `X` is first converted to a window, then converted to a mask using `as.mask`, then handled as above.

### Value

A point pattern (object of class `"ppp"`).

### Author(s)

Adrian Baddeley Adrian.Baddeley@curtin.edu.au

, Rolf Turner r.turner@auckland.ac.nz

and Ege Rubak rubak@math.aau.dk

### See Also

`raster.xy`

### Examples

      pixelcentres(letterR, dimyx=5)

[Package spatstat version 1.63-3 Index]