imager (version 0.14)

subim: Select part of an image

Description

subim selects an image part based on coordinates: it allows you to select a subset of rows, columns, frames etc. Refer to the examples to see how it works

Usage

subim(im, ...)

Arguments

im

an image

...

various conditions defining a rectangular image region

Value

• an image with some parts cut out

Examples

parrots <- load.image(system.file('extdata/parrots.png',package='imager'))
subim(parrots,x < 30) #Only the first 30 columns
subim(parrots,y < 30) #Only the first 30 rows
subim(parrots,x < 30,y < 30) #First 30 columns and rows
subim(parrots, sqrt(x) > 8) #Can use arbitrary expressions
subim(parrots,x > height/2,y > width/2)  #height and width are defined based on the image
subim(parrots,cc==1) #Colour axis is "cc" not "c" here because "c" is an important R function
##Not run
##subim(parrots,x+y==1)
##can't have expressions involving interactions between variables (domain might not be square)